Merge pull request #5 from Slimefun/master

[CI skip] Update fork

.github/configs/yaml-linter.yml

@@ -6,10 +6,13 @@ yaml-files:
 
 rules:
 
-  ## A warning is sufficient here
-  line-length:
-    max: 180
-    level: warning
+  ## Don't warn for line lengths
+  line-length: disable
+
+  truthy:
+    allowed-values: ['true', 'false']
+    ## We don't want it to trigger for the 'on' in our workflows
+    check-keys: false
 
   ## We don't need indentation warnings
   indentation: disable

.github/workflows/discord-webhook.yml

@@ -16,7 +16,7 @@ jobs:
 
     steps:
     - name: Checkout repository
-      uses: actions/checkout@v2.3.3
+      uses: actions/checkout@v2.3.4
     - name: Set up Java JDK 11
       uses: actions/setup-java@v1.4.3
       with:

.github/workflows/maven-compiler.yml

@@ -22,7 +22,7 @@ jobs:
 
     steps:
     - name: Checkout repository
-      uses: actions/checkout@v1
+      uses: actions/checkout@v2
     - name: Set up JDK 1.8
       uses: actions/setup-java@master
       with:

.github/workflows/update-changelog.yml

@@ -16,7 +16,7 @@ jobs:
 
     steps:
       - name: TOC Generator
-        uses: technote-space/toc-generator@v2.4.0
+        uses: technote-space/toc-generator@v2.6.1
         with:
           GITHUB_TOKEN: ${{ secrets.ACCESS_TOKEN }}
           TARGET_PATHS: 'CHANGELOG.md'

.github/workflows/url-checker.yml

@@ -6,7 +6,7 @@ on:
     - master
 
 jobs:
-  build:
+  check:
 
     name: URL Checker
     runs-on: ubuntu-latest
@@ -17,7 +17,7 @@ jobs:
       with:
         git_path: https://github.com/Slimefun/Slimefun4
         file_types: .md,.java,.yml
-        print_all: False
+        print_all: false
         retry_count: 2
         ## These URLs will always be correct, even if their services may be offline right now
         white_listed_patterns: http://textures.minecraft.net/texture/,https://pastebin.com/,https://www.spigotmc.org/threads/spigot-bungeecord-1-16-1.447405/#post-3852349,https://gitlocalize.com/repo/3841

.github/workflows/yaml-linter.yml

@@ -16,8 +16,8 @@ jobs:
 
     steps:
     - name: Checkout repository
-      uses: actions/checkout@v1
+      uses: actions/checkout@v2
     - name: YAML Linter
-      uses: ibiqlik/action-yamllint@v1.0.0
+      uses: ibiqlik/action-yamllint@v3.0.0
       with:
         config_file: '.github/configs/yaml-linter.yml'

CHANGELOG.md

@@ -26,14 +26,39 @@
 ## Release Candidate 18 (TBD)
 
 #### Additions
+* The Smelters Pick now also works on Ancient Debris
+* (API) Added PlayerPreResearchEvent
+* Added a config option to disable network visualizations
+* (API) Added CoolerFeedPlayerEvent
 
 #### Changes
 * Removed 1.13 support
+* Cooling Units can no longer be placed down
+* Heating Coils can no longer be placed down
+* Electric Motors can no longer be placed down
+* Cargo Motors can no longer be placed down
+* Magnets can no longer be placed down
+* Electromagnets can no longer be placed down
+* Performance improvements to Cargo network visualizations
 
 #### Fixes
 * Fixed #2448
 * Fixed #2470
 * Fixed #2478
+* Fixed #2493
+* Fixed a missing slot in the contributors menu
+* Fixed color codes in script downloading screen
+* Fixed #2505
+* Fixed contributors not showing correctly
+* Fixed #2469
+* Fixed #2509
+* Fixed #2499
+* Fixed #2527
+* Fixed #2519
+* Fixed #2517
+* Fixed Magician Talisman sometimes drawing invalid enchantments
+* Fixed id conflicts for external Enchantment sources (e.g. plugins) for the Magician Talisman settings
+* Fixed network visualizers spawning particles for other player heads
 
 ## Release Candidate 17 (17 Oct 2020)
 

README.md

@@ -67,7 +67,7 @@ Well, we asked some users on our [Discord server](#discord) to send us some scre
 | *Screenshot provided by GalaxyKat11#3816* | *Screenshot provided by TamThan#7987* | *Screenshot provided by Kilaruna#4981* |
 
 ## Discord
-You can find Slimefun's community on Discord and connect with **over 2500** users of this plugin from all over the world.<br>
+You can find Slimefun's community on Discord and connect with **over 3000** users of this plugin from all over the world.<br>
 Click the badge down below to join the server for suggestions/questions or other discussions about this plugin.<br>
 We are also hosting a community event every so often, join us to find out more.<br>
 **Important**: We do **not** accept bug reports on discord, please use our [Issue Tracker](https://github.com/Slimefun/Slimefun4/issues) to submit bug reports!

pom.xml

@@ -22,7 +22,7 @@
         <maven.compiler.target>1.8</maven.compiler.target>
 
         <!-- Spigot properties -->
-        <spigot.version>1.16.3</spigot.version>
+        <spigot.version>1.16.4</spigot.version>
         <spigot.javadocs>https://hub.spigotmc.org/javadocs/spigot/</spigot.javadocs>
 
         <!-- Default settings for sonarcloud.io -->
@@ -315,7 +315,7 @@
         <dependency>
             <groupId>com.github.seeseemelk</groupId>
             <artifactId>MockBukkit-v1.16</artifactId>
-            <version>0.13.0</version>
+            <version>0.15.0</version>
             <scope>test</scope>
             <exclusions>
                 <exclusion>
@@ -329,7 +329,7 @@
         <dependency>
             <groupId>org.mockito</groupId>
             <artifactId>mockito-core</artifactId>
-            <version>3.5.13</version>
+            <version>3.6.0</version>
             <scope>test</scope>
         </dependency>
 
@@ -349,7 +349,7 @@
         <dependency>
             <groupId>com.konghq</groupId>
             <artifactId>unirest-java</artifactId>
-            <version>3.11.02</version>
+            <version>3.11.05</version>
             <scope>compile</scope>
             <exclusions>
                 <exclusion>
@@ -363,7 +363,7 @@
         <dependency>
             <groupId>com.sk89q.worldedit</groupId>
             <artifactId>worldedit-bukkit</artifactId>
-            <version>7.2.0-SNAPSHOT</version>
+            <version>7.2.0</version>
             <scope>provided</scope>
             <exclusions>
                 <exclusion>
@@ -381,7 +381,7 @@
         <dependency>
             <groupId>com.gmail.nossr50.mcMMO</groupId>
             <artifactId>mcMMO</artifactId>
-            <version>2.1.149</version>
+            <version>2.1.157</version>
             <scope>provided</scope>
             <exclusions>
                 <exclusion>

src/main/java/io/github/thebusybiscuit/slimefun4/api/events/CoolerFeedPlayerEvent.java

@@ -0,0 +1,113 @@
+package io.github.thebusybiscuit.slimefun4.api.events;
+
+import javax.annotation.Nonnull;
+import javax.annotation.ParametersAreNonnullByDefault;
+
+import org.apache.commons.lang.Validate;
+import org.bukkit.entity.Player;
+import org.bukkit.event.Cancellable;
+import org.bukkit.event.Event;
+import org.bukkit.event.HandlerList;
+import org.bukkit.event.player.PlayerEvent;
+import org.bukkit.inventory.ItemStack;
+import org.bukkit.inventory.meta.PotionMeta;
+import org.bukkit.potion.PotionEffect;
+
+import io.github.thebusybiscuit.slimefun4.implementation.items.backpacks.Cooler;
+
+/**
+ * This {@link Event} is called whenever a {@link Player} is
+ * fed through a {@link Cooler}.
+ *
+ * @author TheBusyBiscuit
+ *
+ * @see Cooler
+ *
+ */
+public class CoolerFeedPlayerEvent extends PlayerEvent implements Cancellable {
+
+    private static final HandlerList handlers = new HandlerList();
+
+    private final Cooler cooler;
+    private final ItemStack coolerItem;
+
+    private ItemStack consumedItem;
+    private boolean cancelled;
+
+    @ParametersAreNonnullByDefault
+    public CoolerFeedPlayerEvent(Player player, Cooler cooler, ItemStack coolerItem, ItemStack consumedItem) {
+        super(player);
+
+        this.cooler = cooler;
+        this.coolerItem = coolerItem;
+        this.consumedItem = consumedItem;
+    }
+
+    /**
+     * This returns the {@link Cooler} that was used.
+     *
+     * @return The {@link Cooler} that was used
+     */
+    @Nonnull
+    public Cooler getCooler() {
+        return cooler;
+    }
+
+    /**
+     * This returns the {@link Cooler} that was used (as an {@link ItemStack})
+     *
+     * @return The {@link Cooler} that was used
+     */
+    @Nonnull
+    public ItemStack getCoolerItem() {
+        return coolerItem;
+    }
+
+    /**
+     * This returns the {@link ItemStack} that was consumed.
+     * The returned {@link ItemStack} is immutable.
+     *
+     * @return The {@link ItemStack} that was consumed
+     */
+    @Nonnull
+    public ItemStack getConsumedItem() {
+        return consumedItem.clone();
+    }
+
+    /**
+     * This sets the {@link ItemStack} that should be "consumed".
+     * The {@link ItemStack} must be a potion.
+     * The {@link Player} will receive the {@link PotionEffect PotionEffects} of the
+     * provided potion upon consumption.
+     * 
+     * @param item
+     *            The new {@link ItemStack}
+     */
+    public void setConsumedItem(@Nonnull ItemStack item) {
+        Validate.notNull(item, "The consumed Item cannot be null!");
+        Validate.isTrue(item.getItemMeta() instanceof PotionMeta, "The item must be a potion!");
+
+        this.consumedItem = item;
+    }
+
+    @Override
+    public boolean isCancelled() {
+        return cancelled;
+    }
+
+    @Override
+    public void setCancelled(boolean cancel) {
+        this.cancelled = cancel;
+    }
+
+    @Nonnull
+    public static HandlerList getHandlerList() {
+        return handlers;
+    }
+
+    @Nonnull
+    @Override
+    public HandlerList getHandlers() {
+        return getHandlerList();
+    }
+}

src/main/java/io/github/thebusybiscuit/slimefun4/api/events/PlayerPreResearchEvent.java

@@ -0,0 +1,83 @@
+package io.github.thebusybiscuit.slimefun4.api.events;
+
+import javax.annotation.Nonnull;
+import javax.annotation.ParametersAreNonnullByDefault;
+
+import org.bukkit.entity.Player;
+import org.bukkit.event.Cancellable;
+import org.bukkit.event.Event;
+import org.bukkit.event.HandlerList;
+import org.apache.commons.lang.Validate;
+import me.mrCookieSlime.Slimefun.Objects.SlimefunItem.SlimefunItem;
+import io.github.thebusybiscuit.slimefun4.core.researching.Research;
+import io.github.thebusybiscuit.slimefun4.implementation.guide.BookSlimefunGuide;
+import io.github.thebusybiscuit.slimefun4.implementation.guide.ChestSlimefunGuide;
+import io.github.thebusybiscuit.slimefun4.implementation.guide.CheatSheetSlimefunGuide;
+
+/**
+ * This {@link Event} is called whenever a {@link Player} clicks to unlock a {@link Research}.
+ * This is called before {@link Research#canUnlock(Player)}.
+ * The {@link Event} is not called for {@link CheatSheetSlimefunGuide}.
+ *
+ * @author uiytt
+ *
+ * @see ChestSlimefunGuide
+ * @see BookSlimefunGuide
+ *
+ */
+public class PlayerPreResearchEvent extends Event implements Cancellable {
+
+    private static final HandlerList handlers = new HandlerList();
+
+    private final Player player;
+    private final Research research;
+    private final SlimefunItem slimefunItem;
+    private boolean cancelled;
+    
+    @ParametersAreNonnullByDefault
+    public PlayerPreResearchEvent(Player p, Research research, SlimefunItem slimefunItem) {
+        Validate.notNull(p, "The Player cannot be null");
+        Validate.notNull(research, "Research cannot be null");
+        Validate.notNull(slimefunItem, "SlimefunItem cannot be null");
+
+        this.player = p;
+        this.research = research;
+        this.slimefunItem = slimefunItem;
+    }
+
+    @Nonnull
+    public Player getPlayer() {
+        return player;
+    }
+
+    @Nonnull
+    public Research getResearch() {
+        return research;
+    }
+
+    @Nonnull
+    public SlimefunItem getSlimefunItem() {
+        return slimefunItem;
+    }
+
+    @Nonnull
+    public static HandlerList getHandlerList() {
+        return handlers;
+    }
+
+    @Nonnull
+    @Override
+    public HandlerList getHandlers() {
+        return getHandlerList();
+    }
+
+    @Override
+    public boolean isCancelled() {
+        return cancelled;
+    }
+
+    @Override
+    public void setCancelled(boolean cancelled) {
+        this.cancelled = cancelled;
+    }
+}

src/main/java/io/github/thebusybiscuit/slimefun4/api/network/Network.java

@@ -9,11 +9,8 @@ import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
 
 import org.apache.commons.lang.Validate;
-import org.bukkit.Color;
 import org.bukkit.Location;
-import org.bukkit.Material;
 import org.bukkit.Particle;
-import org.bukkit.Particle.DustOptions;
 
 import io.github.thebusybiscuit.slimefun4.core.networks.NetworkManager;
 import io.github.thebusybiscuit.slimefun4.implementation.SlimefunPlugin;
@@ -103,13 +100,16 @@ public abstract class Network {
         return regulatorNodes.size() + connectorNodes.size() + terminusNodes.size();
     }
 
+    /**
+     * This method adds the given {@link Location} to this {@link Network}.
+     * 
+     * @param l
+     *            The {@link Location} to add
+     */
     protected void addLocationToNetwork(@Nonnull Location l) {
-        if (connectedLocations.contains(l)) {
-            return;
+        if (connectedLocations.add(l.clone())) {
+            markDirty(l);
         }
-
-        connectedLocations.add(l.clone());
-        markDirty(l);
     }
 
     /**
@@ -211,17 +211,9 @@ public abstract class Network {
      * every {@link Location} that this {@link Network} is connected to.
      */
     public void display() {
-        SlimefunPlugin.runSync(() -> {
-            DustOptions options = new DustOptions(Color.BLUE, 3F);
-
-            for (Location l : connectedLocations) {
-                Material type = l.getBlock().getType();
-
-                if (type == Material.PLAYER_HEAD || type == Material.PLAYER_WALL_HEAD) {
-                    l.getWorld().spawnParticle(Particle.REDSTONE, l.getX() + 0.5, l.getY() + 0.5, l.getZ() + 0.5, 1, 0, 0, 0, 1, options);
-                }
-            }
-        });
+        if (manager.isVisualizerEnabled()) {
+            SlimefunPlugin.runSync(new NetworkVisualizer(this));
+        }
     }
 
     /**

src/main/java/io/github/thebusybiscuit/slimefun4/api/network/NetworkVisualizer.java

@@ -0,0 +1,59 @@
+package io.github.thebusybiscuit.slimefun4.api.network;
+
+import javax.annotation.Nonnull;
+
+import org.bukkit.Color;
+import org.bukkit.Location;
+import org.bukkit.Particle;
+import org.bukkit.Particle.DustOptions;
+
+/**
+ * This class represents the visualizer task of a given {@link Network}.
+ * 
+ * @author TheBusyBiscuit
+ *
+ */
+class NetworkVisualizer implements Runnable {
+
+    /**
+     * The {@link DustOptions} define the {@link Color} and size of our particles.
+     */
+    private final DustOptions options = new DustOptions(Color.BLUE, 3.5F);
+
+    /**
+     * This is our {@link Network} instance.
+     */
+    private final Network network;
+
+    /**
+     * This creates a new {@link NetworkVisualizer} for the given {@link Network}.
+     * 
+     * @param network
+     *            The {@link Network} to visualize
+     */
+    NetworkVisualizer(@Nonnull Network network) {
+        this.network = network;
+    }
+
+    @Override
+    public void run() {
+        for (Location l : network.connectorNodes) {
+            spawnParticles(l);
+        }
+
+        for (Location l : network.terminusNodes) {
+            spawnParticles(l);
+        }
+    }
+
+    /**
+     * This method will spawn the actual particles.
+     * 
+     * @param l
+     *            The {@link Location} of our node
+     */
+    private void spawnParticles(@Nonnull Location l) {
+        l.getWorld().spawnParticle(Particle.REDSTONE, l.getX() + 0.5, l.getY() + 0.5, l.getZ() + 0.5, 1, 0, 0, 0, 1, options);
+    }
+
+}

src/main/java/io/github/thebusybiscuit/slimefun4/core/commands/subcommands/GiveCommand.java

@@ -40,7 +40,7 @@ class GiveCommand extends SubCommand {
                     if (sfItem != null) {
                         giveItem(sender, p, sfItem, args);
                     } else {
-                        SlimefunPlugin.getLocalization().sendMessage(sender, "messages.not-valid-item", true, msg -> msg.replace(PLACEHOLDER_ITEM, args[2]));
+                        SlimefunPlugin.getLocalization().sendMessage(sender, "messages.invalid-item", true, msg -> msg.replace(PLACEHOLDER_ITEM, args[2]));
                     }
                 } else {
                     SlimefunPlugin.getLocalization().sendMessage(sender, "messages.not-online", true, msg -> msg.replace(PLACEHOLDER_PLAYER, args[1]));
@@ -70,7 +70,7 @@ class GiveCommand extends SubCommand {
 
                 SlimefunPlugin.getLocalization().sendMessage(sender, "messages.give-item", true, msg -> msg.replace(PLACEHOLDER_PLAYER, args[1]).replace(PLACEHOLDER_ITEM, sfItem.getItemName()).replace(PLACEHOLDER_AMOUNT, String.valueOf(amount)));
             } else {
-                SlimefunPlugin.getLocalization().sendMessage(sender, "messages.not-valid-amount", true, msg -> msg.replace(PLACEHOLDER_AMOUNT, args[3]));
+                SlimefunPlugin.getLocalization().sendMessage(sender, "messages.invalid-amount", true, msg -> msg.replace(PLACEHOLDER_AMOUNT, args[3]));
             }
         }
     }

src/main/java/io/github/thebusybiscuit/slimefun4/core/commands/subcommands/ResearchCommand.java

@@ -66,7 +66,7 @@ class ResearchCommand extends SubCommand {
                 SlimefunPlugin.getLocalization().sendMessage(player, "messages.give-research", true, variables);
             });
         } else {
-            SlimefunPlugin.getLocalization().sendMessage(sender, "messages.not-valid-research", true, msg -> msg.replace(PLACEHOLDER_RESEARCH, input));
+            SlimefunPlugin.getLocalization().sendMessage(sender, "messages.invalid-research", true, msg -> msg.replace(PLACEHOLDER_RESEARCH, input));
         }
     }
 

src/main/java/io/github/thebusybiscuit/slimefun4/core/guide/options/ContributorsMenu.java

@@ -37,7 +37,7 @@ final class ContributorsMenu {
         menu.setEmptySlotsClickable(false);
         menu.addMenuOpeningHandler(pl -> pl.playSound(pl.getLocation(), Sound.BLOCK_NOTE_BLOCK_HARP, 0.7F, 0.7F));
 
-        ChestMenuUtils.drawBackground(menu, 0, 2, 3, 4, 5, 6, 7, 8, 45, 47, 48, 49, 50, 51, 52);
+        ChestMenuUtils.drawBackground(menu, 0, 2, 3, 4, 5, 6, 7, 8, 45, 47, 48, 49, 50, 51, 53);
 
         menu.addItem(1, new CustomItem(ChestMenuUtils.getBackButton(p, "", "&7" + SlimefunPlugin.getLocalization().getMessage(p, "guide.back.settings"))));
         menu.addMenuClickHandler(1, (pl, slot, item, action) -> {

src/main/java/io/github/thebusybiscuit/slimefun4/core/handlers/RainbowTickHandler.java

@@ -16,6 +16,7 @@ import io.github.thebusybiscuit.cscorelib2.collections.LoopIterator;
 import io.github.thebusybiscuit.slimefun4.api.MinecraftVersion;
 import io.github.thebusybiscuit.slimefun4.implementation.SlimefunPlugin;
 import io.github.thebusybiscuit.slimefun4.implementation.items.blocks.RainbowBlock;
+import io.github.thebusybiscuit.slimefun4.utils.ColoredMaterial;
 import me.mrCookieSlime.CSCoreLibPlugin.Configuration.Config;
 import me.mrCookieSlime.Slimefun.Objects.SlimefunItem.SlimefunItem;
 import me.mrCookieSlime.Slimefun.Objects.handlers.BlockTicker;
@@ -48,10 +49,14 @@ public class RainbowTickHandler extends BlockTicker {
         material = iterator.next();
     }
 
-    public RainbowTickHandler(Material... materials) {
+    public RainbowTickHandler(@Nonnull Material... materials) {
         this(Arrays.asList(materials));
     }
 
+    public RainbowTickHandler(@Nonnull ColoredMaterial material) {
+        this(material.asList());
+    }
+
     /**
      * This method checks whether a given {@link Material} array contains any {@link Material}
      * that would result in a {@link GlassPane} {@link BlockData}.

src/main/java/io/github/thebusybiscuit/slimefun4/core/networks/NetworkManager.java

@@ -29,6 +29,7 @@ import io.github.thebusybiscuit.slimefun4.implementation.listeners.NetworkListen
 public class NetworkManager {
 
     private final int maxNodes;
+    private final boolean enableVisualizer;
     private final List<Network> networks = new LinkedList<>();
 
     /**
@@ -37,8 +38,10 @@ public class NetworkManager {
      * @param maxStepSize
      *            The maximum amount of nodes a {@link Network} can have
      */
-    public NetworkManager(int maxStepSize) {
+    public NetworkManager(int maxStepSize, boolean enableVisualizer) {
         Validate.isTrue(maxStepSize > 0, "The maximal Network size must be above zero!");
+
+        this.enableVisualizer = enableVisualizer;
         maxNodes = maxStepSize;
     }
 
@@ -52,6 +55,15 @@ public class NetworkManager {
         return maxNodes;
     }
 
+    /**
+     * This returns whether the {@link Network} visualizer is enabled.
+     * 
+     * @return Whether the {@link Network} visualizer is enabled
+     */
+    public boolean isVisualizerEnabled() {
+        return enableVisualizer;
+    }
+
     /**
      * This returns a {@link List} of every {@link Network} on the {@link Server}.
      * 

src/main/java/io/github/thebusybiscuit/slimefun4/core/researching/Research.java

@@ -8,6 +8,7 @@ import java.util.function.Consumer;
 
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
+import javax.annotation.ParametersAreNonnullByDefault;
 
 import org.apache.commons.lang.Validate;
 import org.bukkit.Bukkit;
@@ -25,6 +26,9 @@ import io.github.thebusybiscuit.slimefun4.core.services.localization.Language;
 import io.github.thebusybiscuit.slimefun4.implementation.SlimefunPlugin;
 import io.github.thebusybiscuit.slimefun4.implementation.setup.ResearchSetup;
 import io.github.thebusybiscuit.slimefun4.utils.FireworkUtils;
+import io.github.thebusybiscuit.slimefun4.api.events.PlayerPreResearchEvent;
+import io.github.thebusybiscuit.slimefun4.core.guide.SlimefunGuideImplementation;
+import me.mrCookieSlime.Slimefun.Objects.Category;
 import me.mrCookieSlime.Slimefun.Objects.SlimefunItem.SlimefunItem;
 
 /**
@@ -189,6 +193,38 @@ public class Research implements Keyed {
         return items;
     }
 
+    /**
+     * Handle what to do when a {@link Player} clicks on an un-researched item in
+     * a {@link SlimefunGuideImplementation}.
+     *
+     * @param guide The {@link SlimefunGuideImplementation} used.
+     * @param player The {@link Player} who clicked on the item.
+     * @param profile The {@link PlayerProfile} of that {@link Player}.
+     * @param sfItem The {@link SlimefunItem} on which the {@link Player} clicked.
+     * @param category The {@link Category} where the {@link Player} was.
+     * @param page The page number of where the {@link Player} was in the {@link Category};
+     *
+     */
+    @ParametersAreNonnullByDefault
+    public void unlockFromGuide(SlimefunGuideImplementation guide, Player player, PlayerProfile profile, SlimefunItem sfItem, Category category, int page) {
+        if (!SlimefunPlugin.getRegistry().getCurrentlyResearchingPlayers().contains(player.getUniqueId())) {
+            if (profile.hasUnlocked(this)) {
+                guide.openCategory(profile, category, page);
+            } else {
+                PlayerPreResearchEvent event = new PlayerPreResearchEvent(player, this, sfItem);
+                Bukkit.getPluginManager().callEvent(event);
+
+                if (!event.isCancelled()) {
+                    if (this.canUnlock(player)) {
+                        guide.unlockItem(player, sfItem, pl -> guide.openCategory(profile, category, page));
+                    } else {
+                        SlimefunPlugin.getLocalization().sendMessage(player, "messages.not-enough-xp", true);
+                    }
+                }
+            }
+        }
+    }
+
     /**
      * Checks if the {@link Player} can unlock this {@link Research}.
      * 

src/main/java/io/github/thebusybiscuit/slimefun4/core/services/BlockDataService.java

@@ -1,16 +1,31 @@
 package io.github.thebusybiscuit.slimefun4.core.services;
 
 import java.util.Optional;
+import java.util.logging.Level;
 
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+
+import org.apache.commons.lang.Validate;
+
+import org.bukkit.Bukkit;
 import org.bukkit.Keyed;
 import org.bukkit.Material;
 import org.bukkit.NamespacedKey;
 import org.bukkit.block.Block;
 import org.bukkit.block.BlockState;
 import org.bukkit.block.TileState;
+import org.bukkit.persistence.PersistentDataContainer;
 import org.bukkit.persistence.PersistentDataHolder;
+import org.bukkit.persistence.PersistentDataType;
 import org.bukkit.plugin.Plugin;
 
+import io.github.thebusybiscuit.slimefun4.api.MinecraftVersion;
+import io.github.thebusybiscuit.slimefun4.implementation.SlimefunPlugin;
+import io.papermc.lib.PaperLib;
+import io.papermc.lib.features.blockstatesnapshot.BlockStateSnapshotResult;
+import me.mrCookieSlime.Slimefun.api.Slimefun;
+
 /**
  * The {@link BlockDataService} is similar to the {@link CustomItemDataService},
  * it is responsible for storing NBT data inside a {@link TileState}.
@@ -20,11 +35,21 @@ import org.bukkit.plugin.Plugin;
  * @author TheBusyBiscuit
  *
  */
-public class BlockDataService implements PersistentDataService, Keyed {
+public class BlockDataService implements Keyed {
 
     private final NamespacedKey namespacedKey;
 
-    public BlockDataService(Plugin plugin, String key) {
+    /**
+     * This creates a new {@link BlockDataService} for the given {@link Plugin}.
+     * The {@link Plugin} and key will together form a {@link NamespacedKey} used to store
+     * data on a {@link TileState}.
+     * 
+     * @param plugin
+     *            The {@link Plugin} responsible for this service
+     * @param key
+     *            The key under which to store data
+     */
+    public BlockDataService(@Nonnull Plugin plugin, @Nonnull String key) {
         namespacedKey = new NamespacedKey(plugin, key);
     }
 
@@ -41,12 +66,32 @@ public class BlockDataService implements PersistentDataService, Keyed {
      * @param value
      *            The value to store
      */
-    public void setBlockData(Block b, String value) {
-        BlockState state = b.getState();
+    public void setBlockData(@Nonnull Block b, @Nonnull String value) {
+        Validate.notNull(b, "The block cannot be null!");
+        Validate.notNull(value, "The value cannot be null!");
+
+        // Due to a bug on older versions, Persistent Data is nullable for non-snapshots
+        boolean useSnapshot = SlimefunPlugin.getMinecraftVersion().isBefore(MinecraftVersion.MINECRAFT_1_16);
+
+        BlockStateSnapshotResult result = PaperLib.getBlockState(b, useSnapshot);
+        BlockState state = result.getState();
 
         if (state instanceof TileState) {
-            setString((TileState) state, namespacedKey, value);
-            state.update();
+            try {
+                PersistentDataContainer container = ((TileState) state).getPersistentDataContainer();
+                container.set(namespacedKey, PersistentDataType.STRING, value);
+
+                if (result.isSnapshot()) {
+                    state.update();
+                }
+            } catch (Exception x) {
+                Slimefun.getLogger().log(Level.SEVERE, "Please check if your Server Software is up to date!");
+
+                String serverSoftware = PaperLib.isSpigot() && !PaperLib.isPaper() ? "Spigot" : Bukkit.getName();
+                Slimefun.getLogger().log(Level.SEVERE, () -> serverSoftware + " | " + Bukkit.getVersion() + " | " + Bukkit.getBukkitVersion());
+
+                Slimefun.getLogger().log(Level.SEVERE, "An Exception was thrown while trying to set Persistent Data for a Block", x);
+            }
         }
     }
 
@@ -57,11 +102,14 @@ public class BlockDataService implements PersistentDataService, Keyed {
      *            The {@link Block} to retrieve data from
      * @return The stored value
      */
-    public Optional<String> getBlockData(Block b) {
-        BlockState state = b.getState();
+    public Optional<String> getBlockData(@Nonnull Block b) {
+        Validate.notNull(b, "The block cannot be null!");
+
+        BlockState state = PaperLib.getBlockState(b, false).getState();
 
         if (state instanceof TileState) {
-            return getString((TileState) state, namespacedKey);
+            PersistentDataContainer container = ((TileState) state).getPersistentDataContainer();
+            return Optional.ofNullable(container.get(namespacedKey, PersistentDataType.STRING));
         } else {
             return Optional.empty();
         }
@@ -77,9 +125,10 @@ public class BlockDataService implements PersistentDataService, Keyed {
      * 
      * @param type
      *            The {@link Material} to check for
+     * 
      * @return Whether the given {@link Material} is considered a Tile Entity
      */
-    public boolean isTileEntity(Material type) {
+    public boolean isTileEntity(@Nullable Material type) {
         if (type == null || type.isAir()) {
             // Cannot store data on air
             return false;
@@ -104,10 +153,12 @@ public class BlockDataService implements PersistentDataService, Keyed {
         case BARREL:
         case SPAWNER:
         case BEACON:
+            // All of the above Materials are Tile Entities
             return true;
         default:
+            // Otherwise we assume they're not Tile Entities
             return false;
         }
     }
 
-}
+}

src/main/java/io/github/thebusybiscuit/slimefun4/core/services/CustomItemDataService.java

@@ -2,11 +2,17 @@ package io.github.thebusybiscuit.slimefun4.core.services;
 
 import java.util.Optional;
 
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+
+import org.apache.commons.lang.Validate;
 import org.bukkit.Keyed;
 import org.bukkit.Material;
 import org.bukkit.NamespacedKey;
 import org.bukkit.inventory.ItemStack;
 import org.bukkit.inventory.meta.ItemMeta;
+import org.bukkit.persistence.PersistentDataContainer;
+import org.bukkit.persistence.PersistentDataType;
 import org.bukkit.plugin.Plugin;
 
 import me.mrCookieSlime.Slimefun.Objects.SlimefunItem.SlimefunItem;
@@ -22,7 +28,7 @@ import me.mrCookieSlime.Slimefun.api.SlimefunItemStack;
  * @see SlimefunItemStack
  *
  */
-public class CustomItemDataService implements PersistentDataService, Keyed {
+public class CustomItemDataService implements Keyed {
 
     private final NamespacedKey namespacedKey;
 
@@ -35,7 +41,7 @@ public class CustomItemDataService implements PersistentDataService, Keyed {
      * @param key
      *            The key under which to store data
      */
-    public CustomItemDataService(Plugin plugin, String key) {
+    public CustomItemDataService(@Nonnull Plugin plugin, @Nonnull String key) {
         // Null-Validation is performed in the NamespacedKey constructor
         namespacedKey = new NamespacedKey(plugin, key);
     }
@@ -45,14 +51,39 @@ public class CustomItemDataService implements PersistentDataService, Keyed {
         return namespacedKey;
     }
 
-    public void setItemData(ItemStack item, String id) {
+    /**
+     * This method stores the given id on the provided {@link ItemStack} via
+     * persistent data.
+     * 
+     * @param item
+     *            The {@link ItemStack} to store data on
+     * @param id
+     *            The id to store on the {@link ItemStack}
+     */
+    public void setItemData(@Nonnull ItemStack item, @Nonnull String id) {
+        Validate.notNull(item, "The Item cannot be null!");
+        Validate.notNull(id, "Cannot store null on an Item!");
+
         ItemMeta im = item.getItemMeta();
         setItemData(im, id);
         item.setItemMeta(im);
     }
 
-    public void setItemData(ItemMeta im, String id) {
-        setString(im, namespacedKey, id);
+    /**
+     * This method stores the given id on the provided {@link ItemMeta} via
+     * persistent data.
+     * 
+     * @param meta
+     *            The {@link ItemMeta} to store data on
+     * @param id
+     *            The id to store on the {@link ItemMeta}
+     */
+    public void setItemData(@Nonnull ItemMeta meta, @Nonnull String id) {
+        Validate.notNull(meta, "The ItemMeta cannot be null!");
+        Validate.notNull(id, "Cannot store null on an ItemMeta!");
+
+        PersistentDataContainer container = meta.getPersistentDataContainer();
+        container.set(namespacedKey, PersistentDataType.STRING, id);
     }
 
     /**
@@ -65,7 +96,8 @@ public class CustomItemDataService implements PersistentDataService, Keyed {
      * 
      * @return An {@link Optional} describing the result
      */
-    public Optional<String> getItemData(ItemStack item) {
+    @Nonnull
+    public Optional<String> getItemData(@Nullable ItemStack item) {
         if (item == null || item.getType() == Material.AIR || !item.hasItemMeta()) {
             return Optional.empty();
         }
@@ -82,8 +114,12 @@ public class CustomItemDataService implements PersistentDataService, Keyed {
      * 
      * @return An {@link Optional} describing the result
      */
-    public Optional<String> getItemData(ItemMeta meta) {
-        return getString(meta, namespacedKey);
+    @Nonnull
+    public Optional<String> getItemData(@Nonnull ItemMeta meta) {
+        Validate.notNull(meta, "Cannot read data from null!");
+
+        PersistentDataContainer container = meta.getPersistentDataContainer();
+        return Optional.ofNullable(container.get(namespacedKey, PersistentDataType.STRING));
     }
 
 }

src/main/java/io/github/thebusybiscuit/slimefun4/core/services/CustomTextureService.java

@@ -28,6 +28,12 @@ public class CustomTextureService {
     private String version = null;
     private boolean modified = false;
 
+    /**
+     * This creates a new {@link CustomTextureService} for the provided {@link Config}
+     * 
+     * @param config
+     *            The {@link Config} to read custom model data from
+     */
     public CustomTextureService(@Nonnull Config config) {
         this.config = config;
         config.getConfiguration().options().header("This file is used to assign items from Slimefun or any of its addons\n" + "the 'CustomModelData' NBT tag. This can be used in conjunction with a custom resource pack\n" + "to give items custom textures.\n0 means there is no data assigned to that item.\n\n" + "There is no official Slimefun resource pack at the moment.");
@@ -49,6 +55,8 @@ public class CustomTextureService {
         config.setDefaultValue("SLIMEFUN_GUIDE", 0);
 
         config.setDefaultValue("_UI_BACKGROUND", 0);
+        config.setDefaultValue("_UI_NO_PERMISSION", 0);
+        config.setDefaultValue("_UI_NOT_RESEARCHED", 0);
         config.setDefaultValue("_UI_INPUT_SLOT", 0);
         config.setDefaultValue("_UI_OUTPUT_SLOT", 0);
         config.setDefaultValue("_UI_BACK", 0);
@@ -82,22 +90,60 @@ public class CustomTextureService {
         return version;
     }
 
+    /**
+     * This returns true if any custom model data was configured.
+     * If every item id has no configured custom model data, it will return false.
+     * 
+     * @return Whether any custom model data was configured
+     */
     public boolean isActive() {
         return modified;
     }
 
+    /**
+     * This returns the configured custom model data for a given id.
+     * 
+     * @param id
+     *            The id to get the data for
+     * 
+     * @return The configured custom model data
+     */
     public int getModelData(@Nonnull String id) {
         Validate.notNull(id, "Cannot get the ModelData for 'null'");
         return config.getInt(id);
     }
 
+    /**
+     * This method sets the custom model data for this {@link ItemStack}
+     * to the value configured for the provided item id.
+     * 
+     * @param item
+     *            The {@link ItemStack} to set the custom model data for
+     * @param id
+     *            The id for which to get the configured model data
+     */
     public void setTexture(@Nonnull ItemStack item, @Nonnull String id) {
+        Validate.notNull(item, "The Item cannot be null!");
+        Validate.notNull(id, "Cannot store null on an Item!");
+
         ItemMeta im = item.getItemMeta();
         setTexture(im, id);
         item.setItemMeta(im);
     }
 
+    /**
+     * This method sets the custom model data for this {@link ItemMeta}
+     * to the value configured for the provided item id.
+     * 
+     * @param im
+     *            The {@link ItemMeta} to set the custom model data for
+     * @param id
+     *            The id for which to get the configured model data
+     */
     public void setTexture(@Nonnull ItemMeta im, @Nonnull String id) {
+        Validate.notNull(im, "The ItemMeta cannot be null!");
+        Validate.notNull(id, "Cannot store null on an ItemMeta!");
+
         int data = getModelData(id);
         im.setCustomModelData(data == 0 ? null : data);
     }

src/main/java/io/github/thebusybiscuit/slimefun4/core/services/LocalizationService.java

@@ -8,7 +8,6 @@ import java.util.Collection;
 import java.util.HashSet;
 import java.util.LinkedHashMap;
 import java.util.Map;
-import java.util.Optional;
 import java.util.Set;
 import java.util.logging.Level;
 
@@ -21,6 +20,8 @@ import org.bukkit.Server;
 import org.bukkit.configuration.file.FileConfiguration;
 import org.bukkit.configuration.file.YamlConfiguration;
 import org.bukkit.entity.Player;
+import org.bukkit.persistence.PersistentDataContainer;
+import org.bukkit.persistence.PersistentDataType;
 
 import io.github.thebusybiscuit.cscorelib2.math.DoubleHandler;
 import io.github.thebusybiscuit.slimefun4.core.services.localization.Language;
@@ -37,7 +38,7 @@ import me.mrCookieSlime.Slimefun.api.Slimefun;
  * @see Language
  *
  */
-public class LocalizationService extends SlimefunLocalization implements PersistentDataService {
+public class LocalizationService extends SlimefunLocalization {
 
     private static final String LANGUAGE_PATH = "language";
 
@@ -151,10 +152,12 @@ public class LocalizationService extends SlimefunLocalization implements Persist
     @Override
     public Language getLanguage(@Nonnull Player p) {
         Validate.notNull("Player cannot be null!");
-        Optional<String> language = getString(p, languageKey);
 
-        if (language.isPresent()) {
-            Language lang = languages.get(language.get());
+        PersistentDataContainer container = p.getPersistentDataContainer();
+        String language = container.get(languageKey, PersistentDataType.STRING);
+
+        if (language != null) {
+            Language lang = languages.get(language);
 
             if (lang != null) {
                 return lang;
@@ -164,7 +167,7 @@ public class LocalizationService extends SlimefunLocalization implements Persist
         return getDefaultLanguage();
     }
 
-    private void setLanguage(String language, boolean reset) {
+    private void setLanguage(@Nonnull String language, boolean reset) {
         // Clearing out the old Language (if necessary)
         if (reset) {
             getConfig().clear();

src/main/java/io/github/thebusybiscuit/slimefun4/core/services/MetricsService.java

@@ -34,9 +34,26 @@ import kong.unirest.UnirestException;
  */
 public class MetricsService {
 
+    /**
+     * The URL pointing towards the GitHub API.
+     */
     private static final String API_URL = "https://api.github.com/";
+
+    /**
+     * The Name of our repository
+     */
     private static final String REPO_NAME = "MetricsModule";
+
+    /**
+     * The URL pointing towards the /releases/ endpoint of our
+     * Metrics repository
+     */
     private static final String RELEASES_URL = API_URL + "repos/Slimefun/" + REPO_NAME + "/releases/latest";
+
+    /**
+     * The URL pointing towards the download location for a
+     * GitHub release of our Metrics repository
+     */
     private static final String DOWNLOAD_URL = "https://github.com/Slimefun/" + REPO_NAME + "/releases/download";
 
     private final SlimefunPlugin plugin;
@@ -48,9 +65,22 @@ public class MetricsService {
     private boolean hasDownloadedUpdate = false;
 
     static {
-        Unirest.config().concurrency(2, 1).setDefaultHeader("User-Agent", "MetricsModule Auto-Updater").setDefaultHeader("Accept", "application/vnd.github.v3+json").enableCookieManagement(false).cookieSpec("ignoreCookies");
+        // @formatter:off (We want this to stay this nicely aligned :D )
+        Unirest.config()
+            .concurrency(2, 1)
+            .setDefaultHeader("User-Agent", "MetricsModule Auto-Updater")
+            .setDefaultHeader("Accept", "application/vnd.github.v3+json")
+            .enableCookieManagement(false)
+            .cookieSpec("ignoreCookies");
+        // @formatter:on
     }
 
+    /**
+     * This constructs a new instance of our {@link MetricsService}.
+     * 
+     * @param plugin
+     *            Our {@link SlimefunPlugin} instance
+     */
     public MetricsService(@Nonnull SlimefunPlugin plugin) {
         this.plugin = plugin;
         this.parentFolder = new File(plugin.getDataFolder(), "cache" + File.separatorChar + "modules");

src/main/java/io/github/thebusybiscuit/slimefun4/core/services/PersistentDataService.java

@@ -1,35 +0,0 @@
-package io.github.thebusybiscuit.slimefun4.core.services;
-
-import java.util.Optional;
-
-import org.bukkit.NamespacedKey;
-import org.bukkit.persistence.PersistentDataContainer;
-import org.bukkit.persistence.PersistentDataHolder;
-import org.bukkit.persistence.PersistentDataType;
-
-import io.github.thebusybiscuit.cscorelib2.data.PersistentDataAPI;
-import io.github.thebusybiscuit.slimefun4.api.MinecraftVersion;
-
-/**
- * This interface is used to defer calls to Persistent Data and make sure they are only called
- * if the {@link MinecraftVersion} supports it.
- * 
- * @author TheBusyBiscuit
- * 
- * @deprecated This is redundant, we can use {@link PersistentDataAPI} instead.
- *
- */
-@Deprecated
-interface PersistentDataService {
-
-    default void setString(Object obj, NamespacedKey key, String value) {
-        PersistentDataContainer container = ((PersistentDataHolder) obj).getPersistentDataContainer();
-        container.set(key, PersistentDataType.STRING, value);
-    }
-
-    default Optional<String> getString(Object obj, NamespacedKey key) {
-        PersistentDataContainer container = ((PersistentDataHolder) obj).getPersistentDataContainer();
-        return Optional.ofNullable(container.get(key, PersistentDataType.STRING));
-    }
-
-}

src/main/java/io/github/thebusybiscuit/slimefun4/core/services/github/ContributionsConnector.java

@@ -16,11 +16,28 @@ import me.mrCookieSlime.Slimefun.api.Slimefun;
 
 class ContributionsConnector extends GitHubConnector {
 
-    // GitHub Bots that do not count as Contributors
-    // (includes "invalid-email-address" because it is an invalid contributor)
-    private static final List<String> blacklist = Arrays.asList("invalid-email-address", "renovate-bot", "TheBusyBot", "ImgBotApp", "imgbot", "imgbot[bot]", "github-actions[bot]", "gitlocalize-app", "gitlocalize-app[bot]", "mt-gitlocalize");
+    /*
+     * @formatter:off
+     * GitHub Bots that do not count as Contributors
+     * (includes "invalid-email-address" because it is an invalid contributor)
+     */
+    private static final List<String> blacklist = Arrays.asList(
+        "invalid-email-address",
+        "renovate-bot",
+        "TheBusyBot",
+        "ImgBotApp",
+        "imgbot",
+        "imgbot[bot]",
+        "github-actions[bot]",
+        "gitlocalize-app",
+        "gitlocalize-app[bot]",
+        "mt-gitlocalize"
+    );
 
-    // Matches a GitHub name with a Minecraft name.
+    /*
+     * @formatter:on
+     * Matches a GitHub name with a Minecraft name.
+     */
     private static final Map<String, String> aliases = new HashMap<>();
 
     // Should probably be switched to UUIDs at some point...
@@ -82,8 +99,16 @@ class ContributionsConnector extends GitHubConnector {
     }
 
     @Override
-    public String getURLSuffix() {
-        return "/contributors?per_page=100&page=" + page;
+    public String getEndpoint() {
+        return "/contributors";
+    }
+
+    @Override
+    public Map<String, Object> getParameters() {
+        Map<String, Object> parameters = new HashMap<>();
+        parameters.put("per_page", 100);
+        parameters.put("page", page);
+        return parameters;
     }
 
     private void computeContributors(@Nonnull JSONArray array) {

src/main/java/io/github/thebusybiscuit/slimefun4/core/services/github/GitHubActivityConnector.java

@@ -1,6 +1,8 @@
 package io.github.thebusybiscuit.slimefun4.core.services.github;
 
 import java.time.LocalDateTime;
+import java.util.HashMap;
+import java.util.Map;
 
 import javax.annotation.Nonnull;
 import javax.annotation.ParametersAreNonnullByDefault;
@@ -35,8 +37,13 @@ class GitHubActivityConnector extends GitHubConnector {
     }
 
     @Override
-    public String getURLSuffix() {
+    public String getEndpoint() {
         return "";
     }
 
+    @Override
+    public Map<String, Object> getParameters() {
+        return new HashMap<>();
+    }
+
 }

src/main/java/io/github/thebusybiscuit/slimefun4/core/services/github/GitHubConnector.java

@@ -6,12 +6,13 @@ import java.io.FileInputStream;
 import java.io.FileOutputStream;
 import java.io.IOException;
 import java.io.InputStreamReader;
+import java.net.URL;
 import java.nio.charset.StandardCharsets;
+import java.util.Map;
 import java.util.logging.Level;
 
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
-import javax.annotation.ParametersAreNonnullByDefault;
 
 import kong.unirest.HttpResponse;
 import kong.unirest.JsonNode;
@@ -31,22 +32,49 @@ import me.mrCookieSlime.Slimefun.api.Slimefun;
 abstract class GitHubConnector {
 
     private static final String API_URL = "https://api.github.com/";
+    private static final String USER_AGENT = "Slimefun4 (https://github.com/Slimefun)";
 
-    protected File file;
-    protected String repository;
     protected final GitHubService github;
+    private final String url;
+    private File file;
 
-    @ParametersAreNonnullByDefault
-    public GitHubConnector(GitHubService github, String repository) {
+    /**
+     * This creates a new {@link GitHubConnector} for the given repository.
+     * 
+     * @param github
+     *            Our instance of {@link GitHubService}
+     * @param repository
+     *            The repository we want to connect to
+     */
+    GitHubConnector(@Nonnull GitHubService github, @Nonnull String repository) {
         this.github = github;
-        this.repository = repository;
+        this.url = API_URL + "repos/" + repository + getEndpoint();
     }
 
+    /**
+     * This returns the name of our cache {@link File}.
+     * 
+     * @return The cache {@link File} name
+     */
     @Nonnull
     public abstract String getFileName();
 
+    /**
+     * This is our {@link URL} endpoint.
+     * It is the suffix of the {@link URL} we want to connect to.
+     * 
+     * @return Our endpoint
+     */
     @Nonnull
-    public abstract String getURLSuffix();
+    public abstract String getEndpoint();
+
+    /**
+     * This {@link Map} contains the query parameters for our {@link URL}.
+     * 
+     * @return A {@link Map} with our query parameters
+     */
+    @Nonnull
+    public abstract Map<String, Object> getParameters();
 
     /**
      * This method is called when the connection finished successfully.
@@ -63,7 +91,12 @@ abstract class GitHubConnector {
         // Don't do anything by default
     }
 
-    public void pullFile() {
+    /**
+     * This method will connect to GitHub and store the received data inside a local
+     * cache {@link File}.
+     * Make sure to call this method asynchronously!
+     */
+    void download() {
         file = new File("plugins/Slimefun/cache/github/" + getFileName() + ".json");
 
         if (github.isLoggingEnabled()) {
@@ -71,16 +104,19 @@ abstract class GitHubConnector {
         }
 
         try {
-            HttpResponse<JsonNode> resp = Unirest.get(API_URL + "repos/" + repository + getURLSuffix())
-                    .header("User-Agent", "Slimefun4 (https://github.com/Slimefun)")
+            // @formatter:off
+            HttpResponse<JsonNode> response = Unirest.get(url)
+                    .queryString(getParameters())
+                    .header("User-Agent", USER_AGENT)
                     .asJson();
+            // @formatter:on
 
-            if (resp.isSuccess()) {
-                onSuccess(resp.getBody());
-                writeCacheFile(resp.getBody());
+            if (response.isSuccess()) {
+                onSuccess(response.getBody());
+                writeCacheFile(response.getBody());
             } else {
                 if (github.isLoggingEnabled()) {
-                    Slimefun.getLogger().log(Level.WARNING, "Failed to fetch {0}: {1} - {2}", new Object[] { repository + getURLSuffix(), resp.getStatus(), resp.getBody() });
+                    Slimefun.getLogger().log(Level.WARNING, "Failed to fetch {0}: {1} - {2}", new Object[] { url, response.getStatus(), response.getBody() });
                 }
 
                 // It has the cached file, let's just read that then

src/main/java/io/github/thebusybiscuit/slimefun4/core/services/github/GitHubIssuesConnector.java

@@ -1,5 +1,7 @@
 package io.github.thebusybiscuit.slimefun4.core.services.github;
 
+import java.util.HashMap;
+import java.util.Map;
 import java.util.logging.Level;
 
 import javax.annotation.Nonnull;
@@ -50,8 +52,15 @@ class GitHubIssuesConnector extends GitHubConnector {
     }
 
     @Override
-    public String getURLSuffix() {
-        return "/issues?per_page=100";
+    public String getEndpoint() {
+        return "/issues";
+    }
+
+    @Override
+    public Map<String, Object> getParameters() {
+        Map<String, Object> parameters = new HashMap<>();
+        parameters.put("per_page", 100);
+        return parameters;
     }
 
 }

src/main/java/io/github/thebusybiscuit/slimefun4/core/services/github/GitHubService.java

@@ -57,7 +57,8 @@ public class GitHubService {
     }
 
     public void start(@Nonnull SlimefunPlugin plugin) {
-        plugin.getServer().getScheduler().runTaskTimerAsynchronously(plugin, new GitHubTask(this), 80L, 60 * 60 * 20L);
+        GitHubTask task = new GitHubTask(this);
+        plugin.getServer().getScheduler().runTaskTimerAsynchronously(plugin, task, 80L, 60 * 60 * 20L);
     }
 
     /**

src/main/java/io/github/thebusybiscuit/slimefun4/core/services/github/GitHubTask.java

@@ -1,5 +1,6 @@
 package io.github.thebusybiscuit.slimefun4.core.services.github;
 
+import java.io.File;
 import java.io.IOException;
 import java.util.HashMap;
 import java.util.Map;
@@ -38,10 +39,14 @@ class GitHubTask implements Runnable {
 
     @Override
     public void run() {
-        gitHubService.getConnectors().forEach(GitHubConnector::pullFile);
+        gitHubService.getConnectors().forEach(GitHubConnector::download);
         grabTextures();
     }
 
+    /**
+     * This method will pull the skin textures for every {@link Contributor} and store
+     * the {@link UUID} and received skin inside a local cache {@link File}.
+     */
     private void grabTextures() {
         // Store all queried usernames to prevent 429 responses for pinging the
         // same URL twice in one run.

src/main/java/io/github/thebusybiscuit/slimefun4/core/services/localization/SlimefunLocalization.java

@@ -31,14 +31,14 @@ import me.mrCookieSlime.Slimefun.Lists.RecipeType;
  * This is an abstract parent class of {@link LocalizationService}.
  * There is not really much more I can say besides that...
  * 
- * @author TheBusyBiscui
+ * @author TheBusyBiscuit
  * 
  * @see LocalizationService
  *
  */
 public abstract class SlimefunLocalization extends Localization implements Keyed {
 
-    public SlimefunLocalization(@Nonnull SlimefunPlugin plugin) {
+    protected SlimefunLocalization(@Nonnull SlimefunPlugin plugin) {
         super(plugin);
     }
 
@@ -71,6 +71,15 @@ public abstract class SlimefunLocalization extends Localization implements Keyed
      */
     public abstract Language getDefaultLanguage();
 
+    /**
+     * This returns whether a {@link Language} with the given id exists within
+     * the project resources.
+     * 
+     * @param id
+     *            The {@link Language} id
+     * 
+     * @return Whether the project contains a {@link Language} with that id
+     */
     protected abstract boolean hasLanguage(@Nonnull String id);
 
     /**
@@ -82,10 +91,23 @@ public abstract class SlimefunLocalization extends Localization implements Keyed
     @Nonnull
     public abstract Collection<Language> getLanguages();
 
+    /**
+     * This method adds a new {@link Language} with the given id and texture.
+     * 
+     * @param id
+     *            The {@link Language} id
+     * @param texture
+     *            The texture of how this {@link Language} should be displayed
+     */
     protected abstract void addLanguage(@Nonnull String id, @Nonnull String texture);
 
+    /**
+     * This will load every {@link SupportedLanguage} into memory.
+     * To be precise: It performs {@link #addLanguage(String, String)} for every
+     * value of {@link SupportedLanguage}.
+     */
     protected void loadEmbeddedLanguages() {
-        for (SupportedLanguage lang : SupportedLanguage.valuesCache) {
+        for (SupportedLanguage lang : SupportedLanguage.values()) {
             if (lang.isReadyForRelease() || SlimefunPlugin.getUpdater().getBranch() != SlimefunBranch.STABLE) {
                 addLanguage(lang.getLanguageId(), lang.getTexture());
             }

src/main/java/io/github/thebusybiscuit/slimefun4/core/services/localization/SupportedLanguage.java

@@ -58,8 +58,6 @@ enum SupportedLanguage {
     MACEDONIAN("mk", false, "a0e0b0b5d87a855466980a101a757bcdb5f77d9f7287889f3efa998ee0472fc0"),
     TAGALOG("tl", true, "9306c0c1ce6a9c61bb42a572c49e6d0ed20e0e6b3d122cc64c339cbf78e9e937");
 
-    public static final SupportedLanguage[] valuesCache = values();
-
     private final String id;
     private final boolean releaseReady;
     private final String textureHash;
@@ -71,11 +69,22 @@ enum SupportedLanguage {
         this.textureHash = textureHash;
     }
 
+    /**
+     * This returns the id of this {@link Language}.
+     * 
+     * @return
+     */
     @Nonnull
     public String getLanguageId() {
         return id;
     }
 
+    /**
+     * This returns whether this {@link SupportedLanguage} is "release-ready".
+     * A release-ready {@link Language} will be available in RC builds of Slimefun.
+     * 
+     * @return Whether this {@link Language} is "release-ready"
+     */
     public boolean isReadyForRelease() {
         return releaseReady;
     }

src/main/java/io/github/thebusybiscuit/slimefun4/core/services/localization/Translators.java

@@ -120,6 +120,7 @@ public class Translators {
         // Translators - Chinese (Taiwan)
         addTranslator("BrineYT", "HeroBrineKing", SupportedLanguage.CHINESE_TAIWAN, true);
         addTranslator("mio9", SupportedLanguage.CHINESE_TAIWAN, true);
+        addTranslator("ALiangLiang", SupportedLanguage.CHINESE_TAIWAN, true);
 
         // Translators - Arabic
         addTranslator("mohkamfer", "AgentBabbie", SupportedLanguage.ARABIC, false);

src/main/java/io/github/thebusybiscuit/slimefun4/core/services/plugins/ThirdPartyPluginService.java

@@ -101,9 +101,6 @@ public class ThirdPartyPluginService {
         // mcMMO Integration
         if (isPluginInstalled("mcMMO")) {
             try {
-                // This makes sure that the FakeEvent interface is present.
-                // Class.forName("com.gmail.nossr50.events.fake.FakeEvent");
-
                 new McMMOIntegration(plugin);
                 isMcMMOInstalled = true;
             } catch (Exception | LinkageError x) {
@@ -170,7 +167,7 @@ public class ThirdPartyPluginService {
      * @return Whether this is a fake event
      */
     public boolean isEventFaked(@Nonnull Event event) {
-        // TODO: Change this to FakeEvent once the new mcMMO build was released
+        // This can be changed to "FakeEvent" in a later version
         return isMcMMOInstalled && event instanceof FakeBlockBreakEvent;
     }
 

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/SlimefunPlugin.java

@@ -175,11 +175,7 @@ public final class SlimefunPlugin extends JavaPlugin implements SlimefunAddon {
         instance = this;
 
         if (minecraftVersion == MinecraftVersion.UNIT_TEST) {
-            local = new LocalizationService(this, "", null);
-            gpsNetwork = new GPSNetwork();
-            networkManager = new NetworkManager(200);
-            command.register();
-            registry.load(config);
+            onUnitTestStart();
         } else if (getServer().getPluginManager().isPluginEnabled("CS-CoreLib")) {
             getLogger().log(Level.INFO, "CS-CoreLib was detected!");
             long timestamp = System.nanoTime();
@@ -222,7 +218,7 @@ public final class SlimefunPlugin extends JavaPlugin implements SlimefunAddon {
                 networkSize = 1;
             }
 
-            networkManager = new NetworkManager(networkSize);
+            networkManager = new NetworkManager(networkSize, config.getBoolean("networks.enable-visualizer"));
 
             // Setting up bStats
             new Thread(metricsService::start, "Slimefun Metrics").start();
@@ -306,6 +302,14 @@ public final class SlimefunPlugin extends JavaPlugin implements SlimefunAddon {
         }
     }
 
+    private void onUnitTestStart() {
+        local = new LocalizationService(this, "", null);
+        gpsNetwork = new GPSNetwork();
+        networkManager = new NetworkManager(200, true);
+        command.register();
+        registry.load(config);
+    }
+
     @Nonnull
     private String getStartupTime(long timestamp) {
         long ms = (System.nanoTime() - timestamp) / 1000000;

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/guide/BookSlimefunGuide.java

@@ -215,7 +215,11 @@ public class BookSlimefunGuide implements SlimefunGuideImplementation {
 
             ChatComponent component = new ChatComponent(ChatUtils.crop(ChatColor.RED, item.getItemName()) + "\n");
             component.setHoverEvent(new HoverEvent(ChatColor.RESET + item.getItemName(), ChatColor.DARK_RED.toString() + ChatColor.BOLD + SlimefunPlugin.getLocalization().getMessage(p, "guide.locked"), "", ChatColor.GREEN + "> Click to unlock", "", ChatColor.GRAY + "Cost: " + ChatColor.AQUA.toString() + research.getCost() + " Level(s)"));
-            component.setClickEvent(new ClickEvent(key, player -> research(player, profile, item, research, category, page)));
+            component.setClickEvent(new ClickEvent(key, player ->
+                    SlimefunPlugin.runSync(() ->
+                        research.unlockFromGuide(this, player, profile, item, category, page)
+                    )
+            ));
 
             items.add(component);
         } else {
@@ -234,22 +238,6 @@ public class BookSlimefunGuide implements SlimefunGuideImplementation {
         }
     }
 
-    private void research(Player p, PlayerProfile profile, SlimefunItem item, Research research, Category category, int page) {
-        SlimefunPlugin.runSync(() -> {
-            if (!SlimefunPlugin.getRegistry().getCurrentlyResearchingPlayers().contains(p.getUniqueId())) {
-                if (research.canUnlock(p)) {
-                    if (profile.hasUnlocked(research)) {
-                        openCategory(profile, category, page);
-                    } else {
-                        unlockItem(p, item, pl -> openCategory(profile, category, page));
-                    }
-                } else {
-                    SlimefunPlugin.getLocalization().sendMessage(p, "messages.not-enough-xp", true);
-                }
-            }
-        });
-    }
-
     @Override
     public void openSearch(PlayerProfile profile, String input, boolean addToHistory) {
         // We need to write a book implementation for this at some point

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/guide/ChestSlimefunGuide.java

@@ -271,23 +271,12 @@ public class ChestSlimefunGuide implements SlimefunGuideImplementation {
 
         if (isSurvivalMode() && !Slimefun.hasPermission(p, sfitem, false)) {
             List<String> message = SlimefunPlugin.getPermissionsService().getLore(sfitem);
-            menu.addItem(index, new CustomItem(Material.BARRIER, sfitem.getItemName(), message.toArray(new String[0])));
+            menu.addItem(index, new CustomItem(ChestMenuUtils.getNoPermissionItem(), sfitem.getItemName(), message.toArray(new String[0])));
             menu.addMenuClickHandler(index, ChestMenuUtils.getEmptyClickHandler());
         } else if (isSurvivalMode() && research != null && !profile.hasUnlocked(research)) {
-            menu.addItem(index, new CustomItem(Material.BARRIER, ChatColor.WHITE + ItemUtils.getItemName(sfitem.getItem()), "&4&l" + SlimefunPlugin.getLocalization().getMessage(p, "guide.locked"), "", "&a> Click to unlock", "", "&7Cost: &b" + research.getCost() + " Level(s)"));
+            menu.addItem(index, new CustomItem(ChestMenuUtils.getNotResearchedItem(), ChatColor.WHITE + ItemUtils.getItemName(sfitem.getItem()), "&4&l" + SlimefunPlugin.getLocalization().getMessage(p, "guide.locked"), "", "&a> Click to unlock", "", "&7Cost: &b" + research.getCost() + " Level(s)"));
             menu.addMenuClickHandler(index, (pl, slot, item, action) -> {
-                if (!SlimefunPlugin.getRegistry().getCurrentlyResearchingPlayers().contains(pl.getUniqueId())) {
-                    if (research.canUnlock(pl)) {
-                        if (profile.hasUnlocked(research)) {
-                            openCategory(profile, category, page);
-                        } else {
-                            unlockItem(pl, sfitem, player -> openCategory(profile, category, page));
-                        }
-                    } else {
-                        SlimefunPlugin.getLocalization().sendMessage(pl, "messages.not-enough-xp", true);
-                    }
-                }
-
+                research.unlockFromGuide(this, p, profile, sfitem, category, page);
                 return false;
             });
         } else {

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/RadioactiveItem.java

@@ -31,6 +31,9 @@ import me.mrCookieSlime.Slimefun.api.SlimefunItemStack;
  */
 public class RadioactiveItem extends SlimefunItem implements Radioactive, NotPlaceable {
 
+    /**
+     * This is the level of {@link Radioactivity} for this {@link SlimefunItem}
+     */
     private final Radioactivity radioactivity;
 
     /**

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/androids/AndroidType.java

@@ -1,5 +1,7 @@
 package io.github.thebusybiscuit.slimefun4.implementation.items.androids;
 
+import javax.annotation.Nonnull;
+
 /**
  * This enum holds all the different types a {@link ProgrammableAndroid} can represent.
  * 
@@ -55,7 +57,7 @@ public enum AndroidType {
      */
     NON_FIGHTER;
 
-    boolean isType(AndroidType type) {
+    boolean isType(@Nonnull AndroidType type) {
         return type == NONE || type == this || (type == NON_FIGHTER && this != FIGHTER);
     }
 

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/androids/FisherAndroid.java

@@ -57,7 +57,7 @@ public class FisherAndroid extends ProgrammableAndroid {
 
             if (ThreadLocalRandom.current().nextInt(100) < 10 * getTier()) {
                 ItemStack drop = fishingLoot.getRandom();
-                menu.pushItem(drop, getOutputSlots());
+                menu.pushItem(drop.clone(), getOutputSlots());
             }
 
         }

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/androids/Instruction.java

@@ -8,6 +8,7 @@ import java.util.Map;
 import java.util.function.Predicate;
 
 import org.apache.commons.lang.Validate;
+import org.bukkit.Location;
 import org.bukkit.block.Block;
 import org.bukkit.block.BlockFace;
 import org.bukkit.entity.Ageable;
@@ -20,126 +21,223 @@ import io.github.thebusybiscuit.slimefun4.utils.HeadTexture;
 import io.github.thebusybiscuit.slimefun4.utils.SlimefunUtils;
 import me.mrCookieSlime.Slimefun.api.inventory.BlockMenu;
 
-enum Instruction {
+/**
+ * This enum holds every {@link Instruction} for the {@link ProgrammableAndroid}
+ * added by Slimefun itself.
+ * 
+ * @author TheBusyBiscuit
+ *
+ */
+public enum Instruction {
 
-    // Start and End Parts
+    /**
+     * This {@link Instruction} is the starting point of a {@link Script}.
+     */
     START(AndroidType.NONE, HeadTexture.SCRIPT_START),
+
+    /**
+     * This {@link Instruction} is the end token of a {@link Script}.
+     * Once this {@link Instruction} is reached, the {@link Script} will start again.
+     */
     REPEAT(AndroidType.NONE, HeadTexture.SCRIPT_REPEAT),
+
+    /**
+     * This {@link Instruction} will make the {@link ProgrammableAndroid} wait
+     * for one Slimefun tick.
+     */
     WAIT(AndroidType.NONE, HeadTexture.SCRIPT_WAIT),
 
-    // Movement
+    /**
+     * This will make the {@link ProgrammableAndroid} go forward.
+     */
     GO_FORWARD(AndroidType.NON_FIGHTER, HeadTexture.SCRIPT_FORWARD, (android, b, inv, face) -> {
         Block target = b.getRelative(face);
         android.move(b, face, target);
     }),
 
+    /**
+     * This will make the {@link ProgrammableAndroid} go up.
+     */
     GO_UP(AndroidType.NON_FIGHTER, HeadTexture.SCRIPT_UP, (android, b, inv, face) -> {
         Block target = b.getRelative(BlockFace.UP);
         android.move(b, face, target);
     }),
 
+    /**
+     * This will make the {@link ProgrammableAndroid} go down.
+     */
     GO_DOWN(AndroidType.NON_FIGHTER, HeadTexture.SCRIPT_DOWN, (android, b, inv, face) -> {
         Block target = b.getRelative(BlockFace.DOWN);
         android.move(b, face, target);
     }),
 
-    // Directions
+    /**
+     * This will make the {@link ProgrammableAndroid} rotate to the left side.
+     */
     TURN_LEFT(AndroidType.NONE, HeadTexture.SCRIPT_LEFT, (android, b, inv, face) -> {
         int mod = -1;
         android.rotate(b, face, mod);
     }),
 
+    /**
+     * This will make the {@link ProgrammableAndroid} rotate to the right side.
+     */
     TURN_RIGHT(AndroidType.NONE, HeadTexture.SCRIPT_RIGHT, (android, b, inv, face) -> {
         int mod = 1;
         android.rotate(b, face, mod);
     }),
 
-    // Action - Pickaxe
+    /**
+     * This will make a {@link MinerAndroid} dig the {@link Block} above.
+     */
     DIG_UP(AndroidType.MINER, HeadTexture.SCRIPT_DIG_UP, (android, b, inv, face) -> {
         Block target = b.getRelative(BlockFace.UP);
         android.dig(b, inv, target);
     }),
 
+    /**
+     * This will make a {@link MinerAndroid} dig the {@link Block} ahead.
+     */
     DIG_FORWARD(AndroidType.MINER, HeadTexture.SCRIPT_DIG_FORWARD, (android, b, inv, face) -> {
         Block target = b.getRelative(face);
         android.dig(b, inv, target);
     }),
 
+    /**
+     * This will make a {@link MinerAndroid} dig the {@link Block} below.
+     */
     DIG_DOWN(AndroidType.MINER, HeadTexture.SCRIPT_DIG_DOWN, (android, b, inv, face) -> {
         Block target = b.getRelative(BlockFace.DOWN);
         android.dig(b, inv, target);
     }),
 
+    /**
+     * This will make a {@link MinerAndroid} dig the {@link Block} above
+     * and then move itself to that new {@link Location}.
+     */
     MOVE_AND_DIG_UP(AndroidType.MINER, HeadTexture.SCRIPT_DIG_UP, (android, b, inv, face) -> {
         Block target = b.getRelative(BlockFace.UP);
         android.moveAndDig(b, inv, face, target);
     }),
 
+    /**
+     * This will make a {@link MinerAndroid} dig the {@link Block} ahead
+     * and then move itself to that new {@link Location}.
+     */
     MOVE_AND_DIG_FORWARD(AndroidType.MINER, HeadTexture.SCRIPT_DIG_FORWARD, (android, b, inv, face) -> {
         Block target = b.getRelative(face);
         android.moveAndDig(b, inv, face, target);
     }),
 
+    /**
+     * This will make a {@link MinerAndroid} dig the {@link Block} below
+     * and then move itself to that new {@link Location}.
+     */
     MOVE_AND_DIG_DOWN(AndroidType.MINER, HeadTexture.SCRIPT_DIG_DOWN, (android, b, inv, face) -> {
         Block target = b.getRelative(BlockFace.DOWN);
         android.moveAndDig(b, inv, face, target);
     }),
 
-    // Action - Sword
+    /**
+     * This will make a {@link ButcherAndroid} attack any {@link LivingEntity}
+     * ahead of them.
+     */
     ATTACK_MOBS_ANIMALS(AndroidType.FIGHTER, HeadTexture.SCRIPT_ATTACK, (android, b, inv, face) -> {
         Predicate<LivingEntity> predicate = e -> true;
         android.attack(b, face, predicate);
     }),
 
+    /**
+     * This will make a {@link ButcherAndroid} attack any {@link Monster}
+     * ahead of them.
+     */
     ATTACK_MOBS(AndroidType.FIGHTER, HeadTexture.SCRIPT_ATTACK, (android, b, inv, face) -> {
         Predicate<LivingEntity> predicate = e -> e instanceof Monster;
         android.attack(b, face, predicate);
     }),
 
+    /**
+     * This will make a {@link ButcherAndroid} attack any {@link Animals Animal}
+     * ahead of them.
+     */
     ATTACK_ANIMALS(AndroidType.FIGHTER, HeadTexture.SCRIPT_ATTACK, (android, b, inv, face) -> {
         Predicate<LivingEntity> predicate = e -> e instanceof Animals;
         android.attack(b, face, predicate);
     }),
 
+    /**
+     * This will make a {@link ButcherAndroid} attack any <strong>adult</strong>
+     * {@link Animals Animal} ahead of them.
+     */
     ATTACK_ANIMALS_ADULT(AndroidType.FIGHTER, HeadTexture.SCRIPT_ATTACK, (android, b, inv, face) -> {
-        Predicate<LivingEntity> predicate = e -> e instanceof Animals && e instanceof Ageable && ((Ageable) e).isAdult();
+        Predicate<LivingEntity> predicate = e -> e instanceof Animals && ((Ageable) e).isAdult();
         android.attack(b, face, predicate);
     }),
 
-    // Action - Axe
+    /**
+     * This will make a {@link WoodcutterAndroid} chop down the tree in front of them.
+     */
     CHOP_TREE(AndroidType.WOODCUTTER, HeadTexture.SCRIPT_CHOP_TREE),
 
-    // Action - Fishing Rod
+    /**
+     * This {@link Instruction} makes a {@link FisherAndroid} try to catch fish from
+     * the water below.
+     */
     CATCH_FISH(AndroidType.FISHERMAN, HeadTexture.SCRIPT_FISH, (android, b, inv, face) -> android.fish(b, inv)),
 
-    // Action - Hoe
+    /**
+     * This {@link Instruction} will make a {@link FarmerAndroid} try to harvest
+     * the {@link Block} in front of them.
+     */
     FARM_FORWARD(AndroidType.FARMER, HeadTexture.SCRIPT_FARM_FORWARD, (android, b, inv, face) -> {
         Block target = b.getRelative(face);
         android.farm(inv, target);
     }),
 
+    /**
+     * This {@link Instruction} will make a {@link FarmerAndroid} try to harvest
+     * the {@link Block} below.
+     */
     FARM_DOWN(AndroidType.FARMER, HeadTexture.SCRIPT_FARM_DOWN, (android, b, inv, face) -> {
         Block target = b.getRelative(BlockFace.DOWN);
         android.farm(inv, target);
     }),
 
-    // Action - ExoticGarden
+    /**
+     * This {@link Instruction} will make a {@link FarmerAndroid} try to harvest
+     * the {@link Block} in front of them.
+     * 
+     * <strong>This includes plants from ExoticGarden.</strong>
+     */
     FARM_EXOTIC_FORWARD(AndroidType.ADVANCED_FARMER, HeadTexture.SCRIPT_FARM_FORWARD, (android, b, inv, face) -> {
         Block target = b.getRelative(face);
         android.exoticFarm(inv, target);
     }),
 
+    /**
+     * This {@link Instruction} will make a {@link FarmerAndroid} try to harvest
+     * the {@link Block} below.
+     * 
+     * <strong>This includes plants from ExoticGarden.</strong>
+     */
     FARM_EXOTIC_DOWN(AndroidType.ADVANCED_FARMER, HeadTexture.SCRIPT_FARM_DOWN, (android, b, inv, face) -> {
         Block target = b.getRelative(BlockFace.DOWN);
         android.exoticFarm(inv, target);
     }),
 
-    // Action - Interface
+    /**
+     * This {@link Instruction} will force the {@link ProgrammableAndroid} to push their
+     * items into an {@link AndroidInterface} ahead of them.
+     */
     INTERFACE_ITEMS(AndroidType.NONE, HeadTexture.SCRIPT_PUSH_ITEMS, (android, b, inv, face) -> {
         Block target = b.getRelative(face);
         android.depositItems(inv, target);
     }),
 
+    /**
+     * This {@link Instruction} will force the {@link ProgrammableAndroid} to pull
+     * fuel from an {@link AndroidInterface} ahead of them.
+     */
     INTERFACE_FUEL(AndroidType.NONE, HeadTexture.SCRIPT_PULL_FUEL, (android, b, inv, face) -> {
         Block target = b.getRelative(face);
         android.refuel(inv, target);

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/androids/ProgrammableAndroid.java

@@ -58,6 +58,7 @@ import me.mrCookieSlime.Slimefun.Objects.SlimefunItem.interfaces.InventoryBlock;
 import me.mrCookieSlime.Slimefun.Objects.handlers.BlockTicker;
 import me.mrCookieSlime.Slimefun.Objects.handlers.ItemHandler;
 import me.mrCookieSlime.Slimefun.api.BlockStorage;
+import me.mrCookieSlime.Slimefun.api.Slimefun;
 import me.mrCookieSlime.Slimefun.api.SlimefunItemStack;
 import me.mrCookieSlime.Slimefun.api.inventory.BlockMenu;
 import me.mrCookieSlime.Slimefun.api.inventory.BlockMenuPreset;
@@ -69,6 +70,7 @@ public class ProgrammableAndroid extends SlimefunItem implements InventoryBlock,
     private static final int[] BORDER = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 18, 24, 25, 26, 27, 33, 35, 36, 42, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53 };
     private static final int[] OUTPUT_BORDER = { 10, 11, 12, 13, 14, 19, 23, 28, 32, 37, 38, 39, 40, 41 };
     private static final String DEFAULT_SCRIPT = "START-TURN_LEFT-REPEAT";
+    private static final int MAX_SCRIPT_LENGTH = 54;
 
     protected final List<MachineFuel> fuelTypes = new ArrayList<>();
     protected final String texture;
@@ -407,19 +409,23 @@ public class ProgrammableAndroid extends SlimefunItem implements InventoryBlock,
             } else {
                 Script script = scripts.get(target);
                 menu.addItem(index, script.getAsItemStack(this, p), (player, slot, stack, action) -> {
-                    if (action.isShiftClicked()) {
-                        if (script.isAuthor(player)) {
-                            SlimefunPlugin.getLocalization().sendMessage(player, "android.scripts.rating.own", true);
-                        } else if (script.canRate(player)) {
-                            script.rate(player, !action.isRightClicked());
-                            openScriptDownloader(player, b, page);
-                        } else {
-                            SlimefunPlugin.getLocalization().sendMessage(player, "android.scripts.rating.already", true);
+                    try {
+                        if (action.isShiftClicked()) {
+                            if (script.isAuthor(player)) {
+                                SlimefunPlugin.getLocalization().sendMessage(player, "android.scripts.rating.own", true);
+                            } else if (script.canRate(player)) {
+                                script.rate(player, !action.isRightClicked());
+                                openScriptDownloader(player, b, page);
+                            } else {
+                                SlimefunPlugin.getLocalization().sendMessage(player, "android.scripts.rating.already", true);
+                            }
+                        } else if (!action.isRightClicked()) {
+                            script.download();
+                            setScript(b.getLocation(), script.getSourceCode());
+                            openScriptEditor(player, b);
                         }
-                    } else if (!action.isRightClicked()) {
-                        script.download();
-                        setScript(b.getLocation(), script.getSourceCode());
-                        openScriptEditor(player, b);
+                    } catch (Exception x) {
+                        Slimefun.getLogger().log(Level.SEVERE, "An Exception was thrown when a User tried to download a Script!", x);
                     }
 
                     return false;
@@ -534,12 +540,19 @@ public class ProgrammableAndroid extends SlimefunItem implements InventoryBlock,
     }
 
     @Nonnull
-    protected String getScript(@Nonnull Location l) {
+    public String getScript(@Nonnull Location l) {
+        Validate.notNull(l, "Location for android not specified");
         String script = BlockStorage.getLocationInfo(l, "script");
         return script != null ? script : DEFAULT_SCRIPT;
     }
 
-    protected void setScript(@Nonnull Location l, @Nonnull String script) {
+    public void setScript(@Nonnull Location l, @Nonnull String script) {
+        Validate.notNull(l, "Location for android not specified");
+        Validate.notNull(script, "No script given");
+        Validate.isTrue(script.startsWith(Instruction.START.name() + '-'), "A script must begin with a 'START' token.");
+        Validate.isTrue(script.endsWith('-' + Instruction.REPEAT.name()), "A script must end with a 'REPEAT' token.");
+        Validate.isTrue(PatternUtils.DASH.split(script).length <= MAX_SCRIPT_LENGTH, "Scripts may not have more than " + MAX_SCRIPT_LENGTH + " segments");
+
         BlockStorage.addBlockInfo(l, "script", script);
     }
 
@@ -794,12 +807,8 @@ public class ProgrammableAndroid extends SlimefunItem implements InventoryBlock,
     }
 
     private void constructMenu(@Nonnull BlockMenuPreset preset) {
-        for (int i : BORDER) {
-            preset.addItem(i, ChestMenuUtils.getBackground(), ChestMenuUtils.getEmptyClickHandler());
-        }
-        for (int i : OUTPUT_BORDER) {
-            preset.addItem(i, ChestMenuUtils.getOutputSlotTexture(), ChestMenuUtils.getEmptyClickHandler());
-        }
+        preset.drawBackground(BORDER);
+        preset.drawBackground(ChestMenuUtils.getOutputSlotTexture(), OUTPUT_BORDER);
 
         for (int i : getOutputSlots()) {
             preset.addMenuClickHandler(i, new AdvancedMenuClickHandler() {
@@ -828,7 +837,7 @@ public class ProgrammableAndroid extends SlimefunItem implements InventoryBlock,
     }
 
     protected void move(Block b, BlockFace face, Block block) {
-        if (block.getY() > 0 && block.getY() < block.getWorld().getMaxHeight() && (block.getType() == Material.AIR || block.getType() == Material.CAVE_AIR)) {
+        if (block.getY() > 0 && block.getY() < block.getWorld().getMaxHeight() && block.isEmpty()) {
             BlockData blockData = Material.PLAYER_HEAD.createBlockData(data -> {
                 if (data instanceof Rotatable) {
                     Rotatable rotatable = ((Rotatable) data);

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/androids/Script.java

@@ -130,18 +130,19 @@ public final class Script {
     @Nonnull
     ItemStack getAsItemStack(@Nonnull ProgrammableAndroid android, @Nonnull Player p) {
         List<String> lore = new LinkedList<>();
-        lore.add("&7by &r" + getAuthor());
+        lore.add("&7by &f" + getAuthor());
         lore.add("");
-        lore.add("&7Downloads: &r" + getDownloads());
+        lore.add("&7Downloads: &f" + getDownloads());
         lore.add("&7Rating: " + getScriptRatingPercentage());
         lore.add("&a" + getUpvotes() + " \u263A &7| &4\u2639 " + getDownvotes());
         lore.add("");
-        lore.add("&eLeft Click &rto download this Script");
+        lore.add("&eLeft Click &fto download this Script");
         lore.add("&4(This will override your current Script)");
 
         if (canRate(p)) {
-            lore.add("&eShift + Left Click &rto leave a positive Rating");
-            lore.add("&eShift + Right Click &rto leave a negative Rating");
+            lore.add("");
+            lore.add("&eShift + Left Click &fto leave a positive Rating");
+            lore.add("&eShift + Right Click &fto leave a negative Rating");
         }
 
         return new CustomItem(android.getItem(), "&b" + getName(), lore.toArray(new String[0]));

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/cargo/AbstractCargoNode.java

@@ -11,7 +11,7 @@ import io.github.thebusybiscuit.slimefun4.core.handlers.BlockPlaceHandler;
 import io.github.thebusybiscuit.slimefun4.implementation.SlimefunPlugin;
 import io.github.thebusybiscuit.slimefun4.utils.ChatUtils;
 import io.github.thebusybiscuit.slimefun4.utils.ChestMenuUtils;
-import io.github.thebusybiscuit.slimefun4.utils.ColoredMaterials;
+import io.github.thebusybiscuit.slimefun4.utils.ColoredMaterial;
 import io.github.thebusybiscuit.slimefun4.utils.HeadTexture;
 import io.github.thebusybiscuit.slimefun4.utils.NumberUtils;
 import me.mrCookieSlime.Slimefun.Lists.RecipeType;
@@ -100,7 +100,7 @@ abstract class AbstractCargoNode extends SlimefunItem {
             menu.replaceExistingItem(slotCurrent, new CustomItem(HeadTexture.CHEST_TERMINAL.getAsItemStack(), "&bChannel ID: &3" + (channel + 1)));
             menu.addMenuClickHandler(slotCurrent, ChestMenuUtils.getEmptyClickHandler());
         } else {
-            menu.replaceExistingItem(slotCurrent, new CustomItem(ColoredMaterials.WOOL.get(channel), "&bChannel ID: &3" + (channel + 1)));
+            menu.replaceExistingItem(slotCurrent, new CustomItem(ColoredMaterial.WOOL.get(channel), "&bChannel ID: &3" + (channel + 1)));
             menu.addMenuClickHandler(slotCurrent, ChestMenuUtils.getEmptyClickHandler());
         }
 

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/cargo/ReactorAccessPort.java

@@ -1,5 +1,7 @@
 package io.github.thebusybiscuit.slimefun4.implementation.items.cargo;
 
+import javax.annotation.Nonnull;
+
 import org.bukkit.Location;
 import org.bukkit.Material;
 import org.bukkit.block.Block;
@@ -107,22 +109,12 @@ public class ReactorAccessPort extends SlimefunItem {
         });
     }
 
-    private void constructMenu(BlockMenuPreset preset) {
-        for (int i : background) {
-            preset.addItem(i, ChestMenuUtils.getBackground(), ChestMenuUtils.getEmptyClickHandler());
-        }
+    private void constructMenu(@Nonnull BlockMenuPreset preset) {
+        preset.drawBackground(ChestMenuUtils.getBackground(), background);
 
-        for (int i : fuelBorder) {
-            preset.addItem(i, new CustomItem(new ItemStack(Material.LIME_STAINED_GLASS_PANE), " "), ChestMenuUtils.getEmptyClickHandler());
-        }
-
-        for (int i : inputBorder) {
-            preset.addItem(i, new CustomItem(new ItemStack(Material.CYAN_STAINED_GLASS_PANE), " "), ChestMenuUtils.getEmptyClickHandler());
-        }
-
-        for (int i : outputBorder) {
-            preset.addItem(i, new CustomItem(new ItemStack(Material.GREEN_STAINED_GLASS_PANE), " "), ChestMenuUtils.getEmptyClickHandler());
-        }
+        preset.drawBackground(new CustomItem(Material.LIME_STAINED_GLASS_PANE, " "), fuelBorder);
+        preset.drawBackground(new CustomItem(Material.CYAN_STAINED_GLASS_PANE, " "), inputBorder);
+        preset.drawBackground(new CustomItem(Material.GREEN_STAINED_GLASS_PANE, " "), outputBorder);
 
         preset.addItem(1, new CustomItem(SlimefunItems.URANIUM, "&7Fuel Slot", "", "&rThis Slot accepts radioactive Fuel such as:", "&2Uranium &ror &aNeptunium"), ChestMenuUtils.getEmptyClickHandler());
         preset.addItem(22, new CustomItem(SlimefunItems.PLUTONIUM, "&7Byproduct Slot", "", "&rThis Slot contains the Reactor's Byproduct", "&rsuch as &aNeptunium &ror &7Plutonium"), ChestMenuUtils.getEmptyClickHandler());

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/electric/generators/BioGenerator.java

@@ -13,7 +13,7 @@ import me.mrCookieSlime.Slimefun.Objects.SlimefunItem.abstractItems.AGenerator;
 import me.mrCookieSlime.Slimefun.Objects.SlimefunItem.abstractItems.MachineFuel;
 import me.mrCookieSlime.Slimefun.api.SlimefunItemStack;
 
-public abstract class BioGenerator extends AGenerator {
+public class BioGenerator extends AGenerator {
 
     public BioGenerator(Category category, SlimefunItemStack item, RecipeType recipeType, ItemStack[] recipe) {
         super(category, item, recipeType, recipe);

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/electric/generators/CoalGenerator.java

@@ -12,7 +12,7 @@ import me.mrCookieSlime.Slimefun.api.SlimefunItemStack;
 
 import javax.annotation.Nonnull;
 
-public abstract class CoalGenerator extends AGenerator {
+public class CoalGenerator extends AGenerator {
 
     public CoalGenerator(Category category, SlimefunItemStack item, RecipeType recipeType, ItemStack[] recipe) {
         super(category, item, recipeType, recipe);

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/electric/generators/CombustionGenerator.java

@@ -10,7 +10,7 @@ import me.mrCookieSlime.Slimefun.Objects.SlimefunItem.abstractItems.AGenerator;
 import me.mrCookieSlime.Slimefun.Objects.SlimefunItem.abstractItems.MachineFuel;
 import me.mrCookieSlime.Slimefun.api.SlimefunItemStack;
 
-public abstract class CombustionGenerator extends AGenerator {
+public class CombustionGenerator extends AGenerator {
 
     public CombustionGenerator(Category category, SlimefunItemStack item, RecipeType recipeType, ItemStack[] recipe) {
         super(category, item, recipeType, recipe);

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/electric/generators/LavaGenerator.java

@@ -9,7 +9,7 @@ import me.mrCookieSlime.Slimefun.Objects.SlimefunItem.abstractItems.AGenerator;
 import me.mrCookieSlime.Slimefun.Objects.SlimefunItem.abstractItems.MachineFuel;
 import me.mrCookieSlime.Slimefun.api.SlimefunItemStack;
 
-public abstract class LavaGenerator extends AGenerator {
+public class LavaGenerator extends AGenerator {
 
     public LavaGenerator(Category category, SlimefunItemStack item, RecipeType recipeType, ItemStack[] recipe) {
         super(category, item, recipeType, recipe);

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/electric/generators/MagnesiumGenerator.java

@@ -10,7 +10,7 @@ import me.mrCookieSlime.Slimefun.Objects.SlimefunItem.abstractItems.AGenerator;
 import me.mrCookieSlime.Slimefun.Objects.SlimefunItem.abstractItems.MachineFuel;
 import me.mrCookieSlime.Slimefun.api.SlimefunItemStack;
 
-public abstract class MagnesiumGenerator extends AGenerator {
+public class MagnesiumGenerator extends AGenerator {
 
     public MagnesiumGenerator(Category category, SlimefunItemStack item, RecipeType recipeType, ItemStack[] recipe) {
         super(category, item, recipeType, recipe);

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/electric/machines/AbstractEntityAssembler.java

@@ -66,17 +66,9 @@ public abstract class AbstractEntityAssembler<T extends Entity> extends SimpleSl
 
             @Override
             public void init() {
-                for (int i : border) {
-                    addItem(i, ChestMenuUtils.getBackground(), ChestMenuUtils.getEmptyClickHandler());
-                }
-
-                for (int i : headBorder) {
-                    addItem(i, new CustomItem(getHeadBorder(), " "), ChestMenuUtils.getEmptyClickHandler());
-                }
-
-                for (int i : bodyBorder) {
-                    addItem(i, new CustomItem(getBodyBorder(), " "), ChestMenuUtils.getEmptyClickHandler());
-                }
+                drawBackground(border);
+                drawBackground(new CustomItem(getHeadBorder(), " "), headBorder);
+                drawBackground(new CustomItem(getBodyBorder(), " "), bodyBorder);
 
                 constructMenu(this);
             }

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/electric/machines/AutoAnvil.java

@@ -21,7 +21,7 @@ import me.mrCookieSlime.Slimefun.api.inventory.BlockMenu;
  * @author TheBusyBiscuit
  *
  */
-public abstract class AutoAnvil extends AContainer {
+public class AutoAnvil extends AContainer {
 
     private final int repairFactor;
 
@@ -36,11 +36,6 @@ public abstract class AutoAnvil extends AContainer {
         return new ItemStack(Material.IRON_PICKAXE);
     }
 
-    @Override
-    public int getSpeed() {
-        return 1;
-    }
-
     @Override
     public String getMachineIdentifier() {
         return "AUTO_ANVIL";

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/electric/machines/AutoBrewer.java

@@ -3,6 +3,8 @@ package io.github.thebusybiscuit.slimefun4.implementation.items.electric.machine
 import java.util.EnumMap;
 import java.util.Map;
 
+import javax.annotation.Nonnull;
+
 import org.bukkit.Material;
 import org.bukkit.inventory.ItemStack;
 import org.bukkit.inventory.meta.PotionMeta;
@@ -24,7 +26,7 @@ import me.mrCookieSlime.Slimefun.api.inventory.BlockMenu;
  * @author Linox
  *
  */
-public abstract class AutoBrewer extends AContainer {
+public class AutoBrewer extends AContainer {
 
     private static final Map<Material, PotionType> potionRecipes = new EnumMap<>(Material.class);
     private static final Map<PotionType, PotionType> fermentations = new EnumMap<>(PotionType.class);
@@ -143,7 +145,7 @@ public abstract class AutoBrewer extends AContainer {
      * 
      * @return Whether this {@link Material} is a valid potion
      */
-    private boolean isPotion(Material mat) {
+    private boolean isPotion(@Nonnull Material mat) {
         return mat == Material.POTION || mat == Material.SPLASH_POTION || mat == Material.LINGERING_POTION;
     }
 
@@ -152,18 +154,8 @@ public abstract class AutoBrewer extends AContainer {
         return new ItemStack(Material.FISHING_ROD);
     }
 
-    @Override
-    public int getEnergyConsumption() {
-        return 6;
-    }
-
     @Override
     public String getMachineIdentifier() {
         return "AUTO_BREWER";
     }
-
-    @Override
-    public int getCapacity() {
-        return 128;
-    }
 }

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/electric/machines/AutoDisenchanter.java

@@ -51,16 +51,6 @@ public class AutoDisenchanter extends AContainer {
         return new ItemStack(Material.DIAMOND_CHESTPLATE);
     }
 
-    @Override
-    public int getEnergyConsumption() {
-        return 9;
-    }
-
-    @Override
-    public int getCapacity() {
-        return 128;
-    }
-
     @Override
     protected MachineRecipe findNextRecipe(BlockMenu menu) {
         Map<Enchantment, Integer> enchantments = new HashMap<>();
@@ -158,11 +148,6 @@ public class AutoDisenchanter extends AContainer {
         }
     }
 
-    @Override
-    public int getSpeed() {
-        return 1;
-    }
-
     @Override
     public String getMachineIdentifier() {
         return "AUTO_DISENCHANTER";

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/electric/machines/AutoDrier.java

@@ -101,21 +101,6 @@ public class AutoDrier extends AContainer implements RecipeDisplayItem {
         return recipeList;
     }
 
-    @Override
-    public int getEnergyConsumption() {
-        return 5;
-    }
-
-    @Override
-    public int getSpeed() {
-        return 1;
-    }
-
-    @Override
-    public int getCapacity() {
-        return 128;
-    }
-
     @Override
     public String getMachineIdentifier() {
         return "AUTO_DRIER";

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/electric/machines/AutoEnchanter.java

@@ -37,16 +37,6 @@ public class AutoEnchanter extends AContainer {
         return new ItemStack(Material.GOLDEN_CHESTPLATE);
     }
 
-    @Override
-    public int getEnergyConsumption() {
-        return 9;
-    }
-
-    @Override
-    public int getCapacity() {
-        return 128;
-    }
-
     @Override
     protected MachineRecipe findNextRecipe(BlockMenu menu) {
         for (int slot : getInputSlots()) {
@@ -128,11 +118,6 @@ public class AutoEnchanter extends AContainer {
         return sfItem == null || sfItem.isEnchantable();
     }
 
-    @Override
-    public int getSpeed() {
-        return 1;
-    }
-
     @Override
     public String getMachineIdentifier() {
         return "AUTO_ENCHANTER";

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/electric/machines/CarbonPress.java

@@ -11,7 +11,7 @@ import me.mrCookieSlime.Slimefun.Objects.Category;
 import me.mrCookieSlime.Slimefun.Objects.SlimefunItem.abstractItems.AContainer;
 import me.mrCookieSlime.Slimefun.api.SlimefunItemStack;
 
-public abstract class CarbonPress extends AContainer implements RecipeDisplayItem {
+public class CarbonPress extends AContainer implements RecipeDisplayItem {
 
     public CarbonPress(Category category, SlimefunItemStack item, RecipeType recipeType, ItemStack[] recipe) {
         super(category, item, recipeType, recipe);

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/electric/machines/ChargingBench.java

@@ -32,16 +32,6 @@ public class ChargingBench extends AContainer {
         return new ItemStack(Material.GOLDEN_PICKAXE);
     }
 
-    @Override
-    public int getEnergyConsumption() {
-        return 10;
-    }
-
-    @Override
-    public int getCapacity() {
-        return 128;
-    }
-
     @Override
     protected void tick(Block b) {
         if (getCharge(b.getLocation()) < getEnergyConsumption()) {
@@ -81,11 +71,6 @@ public class ChargingBench extends AContainer {
         return false;
     }
 
-    @Override
-    public int getSpeed() {
-        return 1;
-    }
-
     @Override
     public String getMachineIdentifier() {
         return "CHARGING_BENCH";

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/electric/machines/ElectricDustWasher.java

@@ -14,7 +14,7 @@ import me.mrCookieSlime.Slimefun.Objects.SlimefunItem.abstractItems.MachineRecip
 import me.mrCookieSlime.Slimefun.api.SlimefunItemStack;
 import me.mrCookieSlime.Slimefun.api.inventory.BlockMenu;
 
-public abstract class ElectricDustWasher extends AContainer {
+public class ElectricDustWasher extends AContainer {
 
     private OreWasher oreWasher;
     private final boolean legacyMode;

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/electric/machines/ElectricFurnace.java

@@ -12,7 +12,7 @@ import me.mrCookieSlime.Slimefun.Objects.Category;
 import me.mrCookieSlime.Slimefun.Objects.SlimefunItem.abstractItems.AContainer;
 import me.mrCookieSlime.Slimefun.api.SlimefunItemStack;
 
-public abstract class ElectricFurnace extends AContainer {
+public class ElectricFurnace extends AContainer {
 
     public ElectricFurnace(Category category, SlimefunItemStack item, RecipeType recipeType, ItemStack[] recipe) {
         super(category, item, recipeType, recipe);

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/electric/machines/ElectricGoldPan.java

@@ -17,7 +17,7 @@ import me.mrCookieSlime.Slimefun.Objects.SlimefunItem.abstractItems.MachineRecip
 import me.mrCookieSlime.Slimefun.api.SlimefunItemStack;
 import me.mrCookieSlime.Slimefun.api.inventory.BlockMenu;
 
-public abstract class ElectricGoldPan extends AContainer implements RecipeDisplayItem {
+public class ElectricGoldPan extends AContainer implements RecipeDisplayItem {
 
     private final GoldPan goldPan = (GoldPan) SlimefunItems.GOLD_PAN.getItem();
     private final GoldPan netherGoldPan = (GoldPan) SlimefunItems.NETHER_GOLD_PAN.getItem();

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/electric/machines/ElectricIngotFactory.java

@@ -9,7 +9,7 @@ import me.mrCookieSlime.Slimefun.Objects.Category;
 import me.mrCookieSlime.Slimefun.Objects.SlimefunItem.abstractItems.AContainer;
 import me.mrCookieSlime.Slimefun.api.SlimefunItemStack;
 
-public abstract class ElectricIngotFactory extends AContainer implements RecipeDisplayItem {
+public class ElectricIngotFactory extends AContainer implements RecipeDisplayItem {
 
     public ElectricIngotFactory(Category category, SlimefunItemStack item, RecipeType recipeType, ItemStack[] recipe) {
         super(category, item, recipeType, recipe);

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/electric/machines/ElectricIngotPulverizer.java

@@ -53,21 +53,6 @@ public class ElectricIngotPulverizer extends AContainer implements RecipeDisplay
         registerRecipe(3, new ItemStack(Material.GOLD_INGOT), SlimefunItems.GOLD_DUST);
     }
 
-    @Override
-    public int getEnergyConsumption() {
-        return 7;
-    }
-
-    @Override
-    public int getSpeed() {
-        return 1;
-    }
-
-    @Override
-    public int getCapacity() {
-        return 512;
-    }
-
     @Override
     public String getMachineIdentifier() {
         return "ELECTRIC_INGOT_PULVERIZER";

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/electric/machines/ElectricOreGrinder.java

@@ -9,7 +9,7 @@ import me.mrCookieSlime.Slimefun.Objects.Category;
 import me.mrCookieSlime.Slimefun.Objects.SlimefunItem.abstractItems.AContainer;
 import me.mrCookieSlime.Slimefun.api.SlimefunItemStack;
 
-public abstract class ElectricOreGrinder extends AContainer implements RecipeDisplayItem {
+public class ElectricOreGrinder extends AContainer implements RecipeDisplayItem {
 
     public ElectricOreGrinder(Category category, SlimefunItemStack item, RecipeType recipeType, ItemStack[] recipe) {
         super(category, item, recipeType, recipe);

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/electric/machines/ElectricPress.java

@@ -11,7 +11,7 @@ import me.mrCookieSlime.Slimefun.Objects.Category;
 import me.mrCookieSlime.Slimefun.Objects.SlimefunItem.abstractItems.AContainer;
 import me.mrCookieSlime.Slimefun.api.SlimefunItemStack;
 
-public abstract class ElectricPress extends AContainer implements RecipeDisplayItem {
+public class ElectricPress extends AContainer implements RecipeDisplayItem {
 
     public ElectricPress(Category category, SlimefunItemStack item, RecipeType recipeType, ItemStack[] recipe) {
         super(category, item, recipeType, recipe);

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/electric/machines/ElectricSmeltery.java

@@ -35,7 +35,7 @@ import me.mrCookieSlime.Slimefun.api.item_transport.ItemTransportFlow;
  * @author TheBusyBiscuit
  *
  */
-public abstract class ElectricSmeltery extends AContainer {
+public class ElectricSmeltery extends AContainer {
 
     private static final int[] border = { 4, 5, 6, 7, 8, 13, 31, 40, 41, 42, 43, 44 };
     private static final int[] inputBorder = { 0, 1, 2, 3, 9, 12, 18, 21, 27, 30, 36, 37, 38, 39 };

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/electric/machines/ElectrifiedCrucible.java

@@ -12,7 +12,7 @@ import me.mrCookieSlime.Slimefun.Objects.Category;
 import me.mrCookieSlime.Slimefun.Objects.SlimefunItem.abstractItems.AContainer;
 import me.mrCookieSlime.Slimefun.api.SlimefunItemStack;
 
-public abstract class ElectrifiedCrucible extends AContainer {
+public class ElectrifiedCrucible extends AContainer {
 
     public ElectrifiedCrucible(Category category, SlimefunItemStack item, RecipeType recipeType, ItemStack[] recipe) {
         super(category, item, recipeType, recipe);

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/electric/machines/FoodComposter.java

@@ -11,7 +11,7 @@ import me.mrCookieSlime.Slimefun.Objects.Category;
 import me.mrCookieSlime.Slimefun.Objects.SlimefunItem.abstractItems.AContainer;
 import me.mrCookieSlime.Slimefun.api.SlimefunItemStack;
 
-public abstract class FoodComposter extends AContainer implements RecipeDisplayItem {
+public class FoodComposter extends AContainer implements RecipeDisplayItem {
 
     public FoodComposter(Category category, SlimefunItemStack item, RecipeType recipeType, ItemStack[] recipe) {
         super(category, item, recipeType, recipe);

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/electric/machines/FoodFabricator.java

@@ -10,7 +10,7 @@ import me.mrCookieSlime.Slimefun.Objects.Category;
 import me.mrCookieSlime.Slimefun.Objects.SlimefunItem.abstractItems.AContainer;
 import me.mrCookieSlime.Slimefun.api.SlimefunItemStack;
 
-public abstract class FoodFabricator extends AContainer {
+public class FoodFabricator extends AContainer {
 
     public FoodFabricator(Category category, SlimefunItemStack item, RecipeType recipeType, ItemStack[] recipe) {
         super(category, item, recipeType, recipe);

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/electric/machines/Freezer.java

@@ -14,7 +14,7 @@ import me.mrCookieSlime.Slimefun.Objects.SlimefunItem.abstractItems.AContainer;
 import me.mrCookieSlime.Slimefun.Objects.SlimefunItem.abstractItems.MachineRecipe;
 import me.mrCookieSlime.Slimefun.api.SlimefunItemStack;
 
-public abstract class Freezer extends AContainer implements RecipeDisplayItem {
+public class Freezer extends AContainer implements RecipeDisplayItem {
 
     public Freezer(Category category, SlimefunItemStack item, RecipeType recipeType, ItemStack[] recipe) {
         super(category, item, recipeType, recipe);
@@ -52,9 +52,4 @@ public abstract class Freezer extends AContainer implements RecipeDisplayItem {
         return "FREEZER";
     }
 
-    @Override
-    public int getCapacity() {
-        return 256;
-    }
-
 }

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/electric/machines/HeatedPressureChamber.java

@@ -23,7 +23,7 @@ import me.mrCookieSlime.Slimefun.api.inventory.BlockMenuPreset;
 import me.mrCookieSlime.Slimefun.api.inventory.DirtyChestMenu;
 import me.mrCookieSlime.Slimefun.api.item_transport.ItemTransportFlow;
 
-public abstract class HeatedPressureChamber extends AContainer {
+public class HeatedPressureChamber extends AContainer {
 
     public HeatedPressureChamber(Category category, SlimefunItemStack item, RecipeType recipeType, ItemStack[] recipe) {
         super(category, item, recipeType, recipe);

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/electric/machines/Refinery.java

@@ -10,7 +10,7 @@ import me.mrCookieSlime.Slimefun.Objects.Category;
 import me.mrCookieSlime.Slimefun.Objects.SlimefunItem.abstractItems.AContainer;
 import me.mrCookieSlime.Slimefun.api.SlimefunItemStack;
 
-public abstract class Refinery extends AContainer implements RecipeDisplayItem {
+public class Refinery extends AContainer implements RecipeDisplayItem {
 
     public Refinery(Category category, SlimefunItemStack item, RecipeType recipeType, ItemStack[] recipe) {
         super(category, item, recipeType, recipe);

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/geo/GEOMiner.java

@@ -30,7 +30,7 @@ import me.mrCookieSlime.Slimefun.api.SlimefunItemStack;
 import me.mrCookieSlime.Slimefun.api.inventory.BlockMenu;
 import me.mrCookieSlime.Slimefun.api.inventory.BlockMenuPreset;
 
-public abstract class GEOMiner extends AContainer implements RecipeDisplayItem {
+public class GEOMiner extends AContainer implements RecipeDisplayItem {
 
     private static final int[] BORDER = { 0, 1, 2, 3, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 26, 27, 35, 36, 44, 45, 53 };
     private static final int[] OUTPUT_BORDER = { 19, 20, 21, 22, 23, 24, 25, 28, 34, 37, 43, 46, 47, 48, 49, 50, 51, 52 };

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/geo/OilPump.java

@@ -25,7 +25,7 @@ import me.mrCookieSlime.Slimefun.api.inventory.BlockMenu;
 import me.mrCookieSlime.Slimefun.api.inventory.BlockMenuPreset;
 import me.mrCookieSlime.Slimefun.api.item_transport.ItemTransportFlow;
 
-public abstract class OilPump extends AContainer implements RecipeDisplayItem {
+public class OilPump extends AContainer implements RecipeDisplayItem {
 
     private final GEOResource oil;
 

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/magical/talismans/EnderTalisman.java

@@ -1,5 +1,7 @@
 package io.github.thebusybiscuit.slimefun4.implementation.items.magical.talismans;
 
+import javax.annotation.ParametersAreNonnullByDefault;
+
 import org.bukkit.NamespacedKey;
 import org.bukkit.block.EnderChest;
 import org.bukkit.inventory.ItemStack;
@@ -21,12 +23,13 @@ class EnderTalisman extends Talisman {
 
     private static final LockedCategory ENDER_TALISMANS_CATEGORY = new LockedCategory(new NamespacedKey(SlimefunPlugin.instance(), "ender_talismans"), new CustomItem(SlimefunItems.ENDER_TALISMAN, "&7Talismans - &aTier II"), 3, Talisman.TALISMANS_CATEGORY.getKey());
 
+    @ParametersAreNonnullByDefault
     public EnderTalisman(Talisman parent, SlimefunItemStack item) {
         super(ENDER_TALISMANS_CATEGORY, item, new ItemStack[] { SlimefunItems.ENDER_LUMP_3, null, SlimefunItems.ENDER_LUMP_3, null, parent.getItem(), null, SlimefunItems.ENDER_LUMP_3, null, SlimefunItems.ENDER_LUMP_3 }, parent.isConsumable(), parent.isEventCancelled(), parent.getMessageSuffix(), parent.getChance(), parent.getEffects());
     }
 
     @Override
-    public void createEnderTalisman() {
+    void loadEnderTalisman() {
         // Let's override that, otherwise we would be creating Ender Talismans
         // for every Ender Talisman
     }

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/magical/talismans/MagicianTalisman.java

@@ -7,8 +7,13 @@ import java.util.concurrent.ThreadLocalRandom;
 import java.util.logging.Level;
 import java.util.stream.Collectors;
 
-import org.bukkit.Material;
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+import javax.annotation.ParametersAreNonnullByDefault;
+
+import org.apache.commons.lang.Validate;
 import org.bukkit.enchantments.Enchantment;
+import org.bukkit.entity.Player;
 import org.bukkit.inventory.ItemStack;
 
 import io.github.thebusybiscuit.slimefun4.api.items.ItemSetting;
@@ -16,10 +21,18 @@ import io.github.thebusybiscuit.slimefun4.implementation.settings.TalismanEnchan
 import me.mrCookieSlime.Slimefun.api.Slimefun;
 import me.mrCookieSlime.Slimefun.api.SlimefunItemStack;
 
+/**
+ * The {@link MagicianTalisman} is a special kind of {@link Talisman} which awards a {@link Player}
+ * with an extra {@link Enchantment} when they enchant their {@link ItemStack}.
+ * 
+ * @author TheBusyBiscuit
+ *
+ */
 public class MagicianTalisman extends Talisman {
 
     private final Set<TalismanEnchantment> enchantments = new HashSet<>();
 
+    @ParametersAreNonnullByDefault
     public MagicianTalisman(SlimefunItemStack item, ItemStack[] recipe) {
         super(item, recipe, false, false, "magician", 80);
 
@@ -47,13 +60,31 @@ public class MagicianTalisman extends Talisman {
      * 
      * @return An applicable {@link TalismanEnchantment} or null
      */
-    public TalismanEnchantment getRandomEnchantment(ItemStack item) {
-        if (item == null || item.getType() == Material.AIR) {
-            return null;
-        }
+    @Nullable
+    public TalismanEnchantment getRandomEnchantment(@Nonnull ItemStack item, @Nonnull Set<Enchantment> existingEnchantments) {
+        Validate.notNull(item, "The ItemStack cannot be null");
+        Validate.notNull(existingEnchantments, "The Enchantments Set cannot be null");
+
+        // @formatter:off
+        List<TalismanEnchantment> enabled = enchantments.stream()
+                .filter(e -> e.getEnchantment().canEnchantItem(item))
+                .filter(e -> hasConflicts(existingEnchantments, e))
+                .filter(TalismanEnchantment::getValue)
+                .collect(Collectors.toList());
+        // @formatter:on
 
-        List<TalismanEnchantment> enabled = enchantments.stream().filter(e -> e.getEnchantment().canEnchantItem(item)).filter(TalismanEnchantment::getValue).collect(Collectors.toList());
         return enabled.isEmpty() ? null : enabled.get(ThreadLocalRandom.current().nextInt(enabled.size()));
     }
 
+    @ParametersAreNonnullByDefault
+    private boolean hasConflicts(Set<Enchantment> enchantments, TalismanEnchantment ench) {
+        for (Enchantment existing : enchantments) {
+            if (existing.conflictsWith(ench.getEnchantment())) {
+                return false;
+            }
+        }
+
+        return true;
+    }
+
 }

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/magical/talismans/Talisman.java

@@ -5,6 +5,10 @@ import java.util.List;
 import java.util.Optional;
 import java.util.concurrent.ThreadLocalRandom;
 
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+import javax.annotation.ParametersAreNonnullByDefault;
+
 import org.bukkit.ChatColor;
 import org.bukkit.NamespacedKey;
 import org.bukkit.entity.Player;
@@ -44,19 +48,23 @@ public class Talisman extends SlimefunItem {
     protected final PotionEffect[] effects;
     protected final int chance;
 
-    public Talisman(SlimefunItemStack item, ItemStack[] recipe, boolean consumable, boolean cancelEvent, String messageSuffix, PotionEffect... effects) {
+    @ParametersAreNonnullByDefault
+    public Talisman(SlimefunItemStack item, ItemStack[] recipe, boolean consumable, boolean cancelEvent, @Nullable String messageSuffix, PotionEffect... effects) {
         this(item, recipe, consumable, cancelEvent, messageSuffix, 100, effects);
     }
 
-    public Talisman(SlimefunItemStack item, ItemStack[] recipe, String messageSuffix, int chance, PotionEffect... effects) {
+    @ParametersAreNonnullByDefault
+    public Talisman(SlimefunItemStack item, ItemStack[] recipe, @Nullable String messageSuffix, int chance, PotionEffect... effects) {
         this(item, recipe, true, true, messageSuffix, chance, effects);
     }
 
-    public Talisman(SlimefunItemStack item, ItemStack[] recipe, boolean consumable, boolean cancelEvent, String messageSuffix, int chance, PotionEffect... effects) {
+    @ParametersAreNonnullByDefault
+    public Talisman(SlimefunItemStack item, ItemStack[] recipe, boolean consumable, boolean cancelEvent, @Nullable String messageSuffix, int chance, PotionEffect... effects) {
         this(TALISMANS_CATEGORY, item, recipe, consumable, cancelEvent, messageSuffix, chance, effects);
     }
 
-    protected Talisman(Category category, SlimefunItemStack item, ItemStack[] recipe, boolean consumable, boolean cancelEvent, String messageSuffix, int chance, PotionEffect... effects) {
+    @ParametersAreNonnullByDefault
+    protected Talisman(Category category, SlimefunItemStack item, ItemStack[] recipe, boolean consumable, boolean cancelEvent, @Nullable String messageSuffix, int chance, PotionEffect... effects) {
         super(category, item, RecipeType.MAGIC_WORKBENCH, recipe, new CustomItem(item, consumable ? 4 : 1));
 
         this.consumable = consumable;
@@ -81,14 +89,26 @@ public class Talisman extends SlimefunItem {
         }
     }
 
+    /**
+     * This returns whether the {@link Talisman} will be consumed upon use.
+     * 
+     * @return Whether this {@link Talisman} is consumed on use.
+     */
     public boolean isConsumable() {
         return consumable;
     }
 
+    /**
+     * This returns the chance of this {@link Talisman} activating.
+     * The chance will be between 1 and 100.
+     * 
+     * @return The chance of this {@link Talisman} activating.
+     */
     public int getChance() {
         return chance;
     }
 
+    @Nonnull
     public PotionEffect[] getEffects() {
         return effects;
     }
@@ -101,6 +121,7 @@ public class Talisman extends SlimefunItem {
         return cancel;
     }
 
+    @Nullable
     private SlimefunItemStack getEnderVariant() {
         return enderTalisman;
     }
@@ -114,10 +135,10 @@ public class Talisman extends SlimefunItem {
     @Override
     public void load() {
         super.load();
-        createEnderTalisman();
+        loadEnderTalisman();
     }
 
-    protected void createEnderTalisman() {
+    void loadEnderTalisman() {
         EnderTalisman talisman = (EnderTalisman) SlimefunItem.getByItem(getEnderVariant());
         Optional<Research> research = Research.getResearch(new NamespacedKey(SlimefunPlugin.instance(), "ender_talismans"));
 
@@ -126,14 +147,16 @@ public class Talisman extends SlimefunItem {
         }
     }
 
-    private static boolean hasMessage(Talisman talisman) {
+    private static boolean hasMessage(@Nonnull Talisman talisman) {
         return talisman.getMessageSuffix() != null;
     }
 
+    @ParametersAreNonnullByDefault
     public static boolean checkFor(Event e, SlimefunItemStack stack) {
         return checkFor(e, stack.getItem());
     }
 
+    @ParametersAreNonnullByDefault
     public static boolean checkFor(Event e, SlimefunItem item) {
         if (!(item instanceof Talisman)) {
             return false;
@@ -153,7 +176,7 @@ public class Talisman extends SlimefunItem {
 
         if (SlimefunUtils.containsSimilarItem(p.getInventory(), talismanItem, true)) {
             if (Slimefun.hasUnlocked(p, talisman, true)) {
-                activateTalisman(e, p, p.getInventory(), talisman);
+                activateTalisman(e, p, p.getInventory(), talisman, talismanItem);
                 return true;
             } else {
                 return false;
@@ -163,7 +186,7 @@ public class Talisman extends SlimefunItem {
 
             if (SlimefunUtils.containsSimilarItem(p.getEnderChest(), enderTalisman, true)) {
                 if (Slimefun.hasUnlocked(p, talisman, true)) {
-                    activateTalisman(e, p, p.getEnderChest(), talisman);
+                    activateTalisman(e, p, p.getEnderChest(), talisman, enderTalisman);
                     return true;
                 } else {
                     return false;
@@ -174,38 +197,43 @@ public class Talisman extends SlimefunItem {
         }
     }
 
-    private static void activateTalisman(Event e, Player p, Inventory inv, Talisman talisman) {
-        consumeItem(inv, talisman);
+    @ParametersAreNonnullByDefault
+    private static void activateTalisman(Event e, Player p, Inventory inv, Talisman talisman, ItemStack talismanItem) {
+        consumeItem(inv, talisman, talismanItem);
         applyTalismanEffects(p, talisman);
         cancelEvent(e, talisman);
         sendMessage(p, talisman);
     }
 
+    @ParametersAreNonnullByDefault
     private static void applyTalismanEffects(Player p, Talisman talisman) {
         for (PotionEffect effect : talisman.getEffects()) {
             p.addPotionEffect(effect);
         }
     }
 
+    @ParametersAreNonnullByDefault
     private static void cancelEvent(Event e, Talisman talisman) {
         if (e instanceof Cancellable && talisman.isEventCancelled()) {
             ((Cancellable) e).setCancelled(true);
         }
     }
 
+    @ParametersAreNonnullByDefault
     private static void sendMessage(Player p, Talisman talisman) {
         if (hasMessage(talisman)) {
             SlimefunPlugin.getLocalization().sendMessage(p, "messages.talisman." + talisman.getMessageSuffix(), true);
         }
     }
 
-    private static void consumeItem(Inventory inv, Talisman talisman) {
+    @ParametersAreNonnullByDefault
+    private static void consumeItem(Inventory inv, Talisman talisman, ItemStack talismanItem) {
         if (talisman.isConsumable()) {
             ItemStack[] contents = inv.getContents();
             for (int i = 0; i < contents.length; i++) {
                 ItemStack item = contents[i];
 
-                if (SlimefunUtils.isItemSimilar(item, talisman.getItem(), true, false)) {
+                if (SlimefunUtils.isItemSimilar(item, talismanItem, true, false)) {
                     ItemUtils.consumeItem(item, false);
                     return;
                 }

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/multiblocks/ArmorForge.java

@@ -2,6 +2,8 @@ package io.github.thebusybiscuit.slimefun4.implementation.items.multiblocks;
 
 import java.util.List;
 
+import javax.annotation.ParametersAreNonnullByDefault;
+
 import org.bukkit.Material;
 import org.bukkit.Sound;
 import org.bukkit.block.Block;
@@ -14,7 +16,6 @@ import org.bukkit.inventory.ItemStack;
 
 import io.github.thebusybiscuit.cscorelib2.inventory.ItemUtils;
 import io.github.thebusybiscuit.cscorelib2.item.CustomItem;
-import io.github.thebusybiscuit.slimefun4.core.multiblocks.MultiBlockMachine;
 import io.github.thebusybiscuit.slimefun4.implementation.SlimefunPlugin;
 import io.github.thebusybiscuit.slimefun4.utils.SlimefunUtils;
 import io.papermc.lib.PaperLib;
@@ -23,7 +24,7 @@ import me.mrCookieSlime.Slimefun.Objects.Category;
 import me.mrCookieSlime.Slimefun.api.Slimefun;
 import me.mrCookieSlime.Slimefun.api.SlimefunItemStack;
 
-public class ArmorForge extends MultiBlockMachine {
+public class ArmorForge extends BackpackCrafter {
 
     public ArmorForge(Category category, SlimefunItemStack item) {
         super(category, item, new ItemStack[] { null, null, null, null, new ItemStack(Material.ANVIL), null, null, new CustomItem(Material.DISPENSER, "Dispenser (Facing up)"), null }, BlockFace.SELF);
@@ -31,8 +32,8 @@ public class ArmorForge extends MultiBlockMachine {
 
     @Override
     public void onInteract(Player p, Block b) {
-        Block dispBlock = b.getRelative(BlockFace.DOWN);
-        BlockState state = PaperLib.getBlockState(dispBlock, false).getState();
+        Block dispenser = b.getRelative(BlockFace.DOWN);
+        BlockState state = PaperLib.getBlockState(dispenser, false).getState();
 
         if (state instanceof Dispenser) {
             Dispenser disp = (Dispenser) state;
@@ -44,13 +45,7 @@ public class ArmorForge extends MultiBlockMachine {
                     ItemStack output = RecipeType.getRecipeOutputList(this, inputs.get(i)).clone();
 
                     if (Slimefun.hasUnlocked(p, output, true)) {
-                        Inventory outputInv = findOutputInventory(output, dispBlock, inv);
-
-                        if (outputInv != null) {
-                            craft(p, output, inv, outputInv);
-                        } else {
-                            SlimefunPlugin.getLocalization().sendMessage(p, "machines.full-inventory", true);
-                        }
+                        craft(p, output, inv, dispenser);
                     }
 
                     return;
@@ -71,26 +66,35 @@ public class ArmorForge extends MultiBlockMachine {
         return true;
     }
 
-    private void craft(Player p, ItemStack output, Inventory inv, Inventory outputInv) {
-        for (int j = 0; j < 9; j++) {
-            ItemStack item = inv.getContents()[j];
+    @ParametersAreNonnullByDefault
+    private void craft(Player p, ItemStack output, Inventory inv, Block dispenser) {
+        Inventory fakeInv = createVirtualInventory(inv);
+        Inventory outputInv = findOutputInventory(output, dispenser, inv, fakeInv);
 
-            if (item != null && item.getType() != Material.AIR) {
-                ItemUtils.consumeItem(item, true);
-            }
-        }
+        if (outputInv != null) {
+            for (int j = 0; j < 9; j++) {
+                ItemStack item = inv.getContents()[j];
 
-        for (int j = 0; j < 4; j++) {
-            int current = j;
-
-            SlimefunPlugin.runSync(() -> {
-                if (current < 3) {
-                    p.getWorld().playSound(p.getLocation(), Sound.BLOCK_ANVIL_USE, 1F, 2F);
-                } else {
-                    p.getWorld().playSound(p.getLocation(), Sound.ENTITY_ARROW_HIT_PLAYER, 1F, 1F);
-                    outputInv.addItem(output);
+                if (item != null && item.getType() != Material.AIR) {
+                    ItemUtils.consumeItem(item, true);
                 }
-            }, j * 20L);
+            }
+
+            for (int j = 0; j < 4; j++) {
+                int current = j;
+
+                SlimefunPlugin.runSync(() -> {
+                    if (current < 3) {
+                        p.getWorld().playSound(p.getLocation(), Sound.BLOCK_ANVIL_USE, 1F, 2F);
+                    } else {
+                        p.getWorld().playSound(p.getLocation(), Sound.ENTITY_ARROW_HIT_PLAYER, 1F, 1F);
+                        outputInv.addItem(output);
+                    }
+                }, j * 20L);
+            }
+
+        } else {
+            SlimefunPlugin.getLocalization().sendMessage(p, "machines.full-inventory", true);
         }
     }
 

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/multiblocks/BackpackCrafter.java

@@ -32,6 +32,7 @@ import me.mrCookieSlime.Slimefun.api.SlimefunItemStack;
  * 
  * @see EnhancedCraftingTable
  * @see MagicWorkbench
+ * @see ArmorForge
  *
  */
 abstract class BackpackCrafter extends MultiBlockMachine {

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/listeners/CoolerListener.java

@@ -15,6 +15,7 @@ import org.bukkit.inventory.ItemStack;
 import org.bukkit.inventory.meta.PotionMeta;
 import org.bukkit.potion.PotionEffect;
 
+import io.github.thebusybiscuit.slimefun4.api.events.CoolerFeedPlayerEvent;
 import io.github.thebusybiscuit.slimefun4.api.player.PlayerBackpack;
 import io.github.thebusybiscuit.slimefun4.api.player.PlayerProfile;
 import io.github.thebusybiscuit.slimefun4.implementation.SlimefunPlugin;
@@ -37,11 +38,13 @@ import me.mrCookieSlime.Slimefun.api.Slimefun;
  */
 public class CoolerListener implements Listener {
 
+    private final SlimefunPlugin plugin;
     private final Cooler cooler;
 
     public CoolerListener(@Nonnull SlimefunPlugin plugin, @Nonnull Cooler cooler) {
         plugin.getServer().getPluginManager().registerEvents(this, plugin);
 
+        this.plugin = plugin;
         this.cooler = cooler;
     }
 
@@ -93,12 +96,12 @@ public class CoolerListener implements Listener {
     private void takeJuiceFromCooler(@Nonnull Player p, @Nonnull ItemStack cooler) {
         PlayerProfile.getBackpack(cooler, backpack -> {
             if (backpack != null) {
-                SlimefunPlugin.runSync(() -> consumeJuice(p, backpack));
+                SlimefunPlugin.runSync(() -> consumeJuice(p, cooler, backpack));
             }
         });
     }
 
-    private boolean consumeJuice(@Nonnull Player p, @Nonnull PlayerBackpack backpack) {
+    private boolean consumeJuice(@Nonnull Player p, @Nonnull ItemStack coolerItem, @Nonnull PlayerBackpack backpack) {
         Inventory inv = backpack.getInventory();
         int slot = -1;
 
@@ -112,17 +115,26 @@ public class CoolerListener implements Listener {
         }
 
         if (slot >= 0) {
-            PotionMeta im = (PotionMeta) inv.getItem(slot).getItemMeta();
+            ItemStack item = inv.getItem(slot);
+            CoolerFeedPlayerEvent event = new CoolerFeedPlayerEvent(p, cooler, coolerItem, item);
+            plugin.getServer().getPluginManager().callEvent(event);
 
-            for (PotionEffect effect : im.getCustomEffects()) {
-                p.addPotionEffect(effect);
+            if (!event.isCancelled()) {
+                PotionMeta im = (PotionMeta) event.getConsumedItem().getItemMeta();
+
+                for (PotionEffect effect : im.getCustomEffects()) {
+                    p.addPotionEffect(effect);
+                }
+
+                p.setSaturation(6F);
+                p.playSound(p.getLocation(), Sound.ENTITY_GENERIC_DRINK, 1F, 1F);
+                inv.setItem(slot, null);
+                backpack.markDirty();
+
+                return true;
+            } else {
+                return false;
             }
-
-            p.setSaturation(6F);
-            p.playSound(p.getLocation(), Sound.ENTITY_GENERIC_DRINK, 1F, 1F);
-            inv.setItem(slot, null);
-            backpack.markDirty();
-            return true;
         }
 
         return false;

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/listeners/SlimefunBootsListener.java

@@ -40,7 +40,7 @@ public class SlimefunBootsListener implements Listener {
     @EventHandler(priority = EventPriority.HIGH, ignoreCancelled = true)
     public void onDamage(EntityDamageEvent e) {
         if (e.getEntity() instanceof Player && e.getCause() == DamageCause.FALL) {
-                onFallDamage(e);
+            onFallDamage(e);
         }
     }
 

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/listeners/TalismanListener.java

@@ -3,8 +3,8 @@ package io.github.thebusybiscuit.slimefun4.implementation.listeners;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.List;
+import java.util.Map;
 import java.util.Random;
-import java.util.Set;
 import java.util.concurrent.ThreadLocalRandom;
 
 import javax.annotation.Nonnull;
@@ -231,26 +231,28 @@ public class TalismanListener implements Listener {
     @EventHandler
     public void onEnchant(EnchantItemEvent e) {
         Random random = ThreadLocalRandom.current();
+        Map<Enchantment, Integer> enchantments = e.getEnchantsToAdd();
 
+        // Magician Talisman
         if (Talisman.checkFor(e, SlimefunItems.TALISMAN_MAGICIAN)) {
             MagicianTalisman talisman = (MagicianTalisman) SlimefunItems.TALISMAN_MAGICIAN.getItem();
-            TalismanEnchantment enchantment = talisman.getRandomEnchantment(e.getItem());
+            TalismanEnchantment enchantment = talisman.getRandomEnchantment(e.getItem(), enchantments.keySet());
 
             if (enchantment != null) {
-                e.getEnchantsToAdd().put(enchantment.getEnchantment(), enchantment.getLevel());
+                enchantments.put(enchantment.getEnchantment(), enchantment.getLevel());
             }
         }
 
-        if (!e.getEnchantsToAdd().containsKey(Enchantment.SILK_TOUCH) && Enchantment.LOOT_BONUS_BLOCKS.canEnchantItem(e.getItem()) && Talisman.checkFor(e, SlimefunItems.TALISMAN_WIZARD)) {
-            Set<Enchantment> enchantments = e.getEnchantsToAdd().keySet();
+        // Wizard Talisman
+        if (!enchantments.containsKey(Enchantment.SILK_TOUCH) && Enchantment.LOOT_BONUS_BLOCKS.canEnchantItem(e.getItem()) && Talisman.checkFor(e, SlimefunItems.TALISMAN_WIZARD)) {
 
-            for (Enchantment enchantment : enchantments) {
+            for (Enchantment enchantment : enchantments.keySet()) {
                 if (random.nextInt(100) < 40) {
                     e.getEnchantsToAdd().put(enchantment, random.nextInt(3) + 1);
                 }
             }
 
-            e.getEnchantsToAdd().put(Enchantment.LOOT_BONUS_BLOCKS, random.nextInt(3) + 3);
+            enchantments.put(Enchantment.LOOT_BONUS_BLOCKS, random.nextInt(3) + 3);
         }
     }
 

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/listeners/crafting/AnvilListener.java

@@ -2,7 +2,6 @@ package io.github.thebusybiscuit.slimefun4.implementation.listeners.crafting;
 
 import javax.annotation.Nonnull;
 
-import org.bukkit.block.BrewingStand;
 import org.bukkit.entity.Player;
 import org.bukkit.event.Event.Result;
 import org.bukkit.event.EventHandler;
@@ -15,8 +14,8 @@ import io.github.thebusybiscuit.slimefun4.implementation.SlimefunPlugin;
 import me.mrCookieSlime.Slimefun.Objects.SlimefunItem.SlimefunItem;
 
 /**
- * This {@link Listener} prevents any {@link SlimefunItem} from being used in a
- * {@link BrewingStand}.
+ * This {@link Listener} prevents any {@link SlimefunItem} from being used in an
+ * anvil.
  * 
  * @author TheBusyBiscuit
  *

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/listeners/crafting/BrewingStandListener.java

@@ -17,7 +17,7 @@ import me.mrCookieSlime.Slimefun.Objects.SlimefunItem.SlimefunItem;
 
 /**
  * This {@link Listener} prevents any {@link SlimefunItem} from being used in a
- * {@link BrewingStand}.
+ * brewing stand.
  * 
  * @author VoidAngel
  * @author SoSeDiK

src/main/java/io/github/thebusybiscuit/slimefun4/implementation/settings/TalismanEnchantment.java

@@ -21,7 +21,7 @@ public class TalismanEnchantment extends ItemSetting<Boolean> {
     private final int level;
 
     public TalismanEnchantment(@Nonnull Enchantment enchantment, int level) {
-        super("allow-enchantments." + enchantment.getKey().getKey() + ".level." + level, true);
+        super("allow-enchantments." + enchantment.getKey().getNamespace() + '.' + enchantment.getKey().getKey() + ".level." + level, true);
 
         this.enchantment = enchantment;
         this.level = level;

src/main/java/io/github/thebusybiscuit/slimefun4/utils/ChestMenuUtils.java

@@ -29,6 +29,9 @@ public final class ChestMenuUtils {
     private static final ItemStack INPUT_SLOT = new SlimefunItemStack("_UI_INPUT_SLOT", Material.CYAN_STAINED_GLASS_PANE, " ");
     private static final ItemStack OUTPUT_SLOT = new SlimefunItemStack("_UI_OUTPUT_SLOT", Material.ORANGE_STAINED_GLASS_PANE, " ");
 
+    private static final ItemStack NO_PERMISSION = new SlimefunItemStack("_UI_NO_PERMISSION", Material.BARRIER, "No Permission");
+    private static final ItemStack NOT_RESEARCHED = new SlimefunItemStack("_UI_NOT_RESEARCHED", Material.BARRIER, "Not researched");
+
     private static final ItemStack BACK_BUTTON = new SlimefunItemStack("_UI_BACK", Material.ENCHANTED_BOOK, "&7\u21E6 Back", meta -> meta.addItemFlags(ItemFlag.HIDE_ENCHANTS));
     private static final ItemStack MENU_BUTTON = new SlimefunItemStack("_UI_MENU", Material.COMPARATOR, "&eSettings / Info", "", "&7\u21E8 Click to see more");
     private static final ItemStack SEARCH_BUTTON = new SlimefunItemStack("_UI_SEARCH", Material.NAME_TAG, "&bSearch");
@@ -46,6 +49,16 @@ public final class ChestMenuUtils {
         return UI_BACKGROUND;
     }
 
+    @Nonnull
+    public static ItemStack getNoPermissionItem() {
+        return NO_PERMISSION;
+    }
+
+    @Nonnull
+    public static ItemStack getNotResearchedItem() {
+        return NOT_RESEARCHED;
+    }
+
     @Nonnull
     public static ItemStack getInputSlotTexture() {
         return INPUT_SLOT;

src/main/java/io/github/thebusybiscuit/slimefun4/utils/ColoredMaterial.java

@@ -4,6 +4,10 @@ import java.util.Arrays;
 import java.util.Collections;
 import java.util.List;
 
+import javax.annotation.Nonnull;
+
+import org.apache.commons.lang.Validate;
+import org.bukkit.DyeColor;
 import org.bukkit.Material;
 
 import io.github.thebusybiscuit.slimefun4.utils.tags.SlimefunTag;
@@ -17,18 +21,14 @@ import io.github.thebusybiscuit.slimefun4.utils.tags.SlimefunTag;
  * @see SlimefunTag
  *
  */
-public final class ColoredMaterials {
+public enum ColoredMaterial {
 
-    /**
-     * We don't want any instances of this class, so we set the
-     * constructor to be private.
-     */
-    private ColoredMaterials() {}
+    // @formatter:off (We want this to stay formatted like this)
     
     /**
      * This {@link List} contains all wool colors ordered by their appearance ingame.
      */
-    public static final List<Material> WOOL = Collections.unmodifiableList(Arrays.asList(
+    WOOL(new Material[] {
             Material.WHITE_WOOL,
             Material.ORANGE_WOOL,
             Material.MAGENTA_WOOL,
@@ -45,12 +45,12 @@ public final class ColoredMaterials {
             Material.GREEN_WOOL,
             Material.RED_WOOL,
             Material.BLACK_WOOL
-    ));
+    }),
 
     /**
      * This {@link List} contains all stained glass colors ordered by their appearance ingame.
      */
-    public static final List<Material> STAINED_GLASS = Collections.unmodifiableList(Arrays.asList(
+    STAINED_GLASS(new Material[] {
             Material.WHITE_STAINED_GLASS,
             Material.ORANGE_STAINED_GLASS,
             Material.MAGENTA_STAINED_GLASS,
@@ -67,12 +67,12 @@ public final class ColoredMaterials {
             Material.GREEN_STAINED_GLASS,
             Material.RED_STAINED_GLASS,
             Material.BLACK_STAINED_GLASS
-    ));
+    }),
 
     /**
      * This {@link List} contains all stained glass pane colors ordered by their appearance ingame.
      */
-    public static final List<Material> STAINED_GLASS_PANE = Collections.unmodifiableList(Arrays.asList(
+    STAINED_GLASS_PANE(new Material[] {
             Material.WHITE_STAINED_GLASS_PANE,
             Material.ORANGE_STAINED_GLASS_PANE,
             Material.MAGENTA_STAINED_GLASS_PANE,
@@ -89,12 +89,12 @@ public final class ColoredMaterials {
             Material.GREEN_STAINED_GLASS_PANE,
             Material.RED_STAINED_GLASS_PANE,
             Material.BLACK_STAINED_GLASS_PANE
-    ));
+    }),
 
     /**
      * This {@link List} contains all terracotta colors ordered by their appearance ingame.
      */
-    public static final List<Material> TERRACOTTA = Collections.unmodifiableList(Arrays.asList(
+    TERRACOTTA(new Material[] {
             Material.WHITE_TERRACOTTA,
             Material.ORANGE_TERRACOTTA,
             Material.MAGENTA_TERRACOTTA,
@@ -111,12 +111,12 @@ public final class ColoredMaterials {
             Material.GREEN_TERRACOTTA,
             Material.RED_TERRACOTTA,
             Material.BLACK_TERRACOTTA
-    ));
+    }),
 
     /**
      * This {@link List} contains all glazed terracotta colors ordered by their appearance ingame.
      */
-    public static final List<Material> GLAZED_TERRACOTTA = Collections.unmodifiableList(Arrays.asList(
+    GLAZED_TERRACOTTA(new Material[] {
             Material.WHITE_GLAZED_TERRACOTTA,
             Material.ORANGE_GLAZED_TERRACOTTA,
             Material.MAGENTA_GLAZED_TERRACOTTA,
@@ -133,12 +133,12 @@ public final class ColoredMaterials {
             Material.GREEN_GLAZED_TERRACOTTA,
             Material.RED_GLAZED_TERRACOTTA,
             Material.BLACK_GLAZED_TERRACOTTA
-    ));
+    }),
 
     /**
      * This {@link List} contains all concrete colors ordered by their appearance ingame.
      */
-    public static final List<Material> CONCRETE = Collections.unmodifiableList(Arrays.asList(
+    CONCRETE(new Material[] {
             Material.WHITE_CONCRETE,
             Material.ORANGE_CONCRETE,
             Material.MAGENTA_CONCRETE,
@@ -155,6 +155,42 @@ public final class ColoredMaterials {
             Material.GREEN_CONCRETE,
             Material.RED_CONCRETE,
             Material.BLACK_CONCRETE
-    ));
+    });
+    
+    // @formatter:on
+
+    private final List<Material> list;
+
+    /**
+     * This creates a new constant of {@link ColoredMaterial}.
+     * The array must have a length of 16 and cannot contain null elements!
+     * 
+     * @param materials
+     *            The {@link Material Materials} for this {@link ColoredMaterial}.
+     */
+    ColoredMaterial(@Nonnull Material[] materials) {
+        Validate.noNullElements(materials, "The List cannot contain any null elements");
+        Validate.isTrue(materials.length == 16, "Expected 16, received: " + materials.length + ". Did you miss a color?");
+
+        list = Collections.unmodifiableList(Arrays.asList(materials));
+    }
+
+    @Nonnull
+    public List<Material> asList() {
+        return list;
+    }
+
+    @Nonnull
+    public Material get(int index) {
+        Validate.isTrue(index >= 0 && index < 16, "The index must be between 0 and 15 (inclusive).");
+
+        return list.get(index);
+    }
+
+    public Material get(@Nonnull DyeColor color) {
+        Validate.notNull(color, "Color cannot be null!");
+
+        return get(color.ordinal());
+    }
 
 }

src/main/java/io/github/thebusybiscuit/slimefun4/utils/NumberUtils.java

@@ -1,6 +1,7 @@
 package io.github.thebusybiscuit.slimefun4.utils;
 
 import java.text.DecimalFormat;
+import java.text.DecimalFormatSymbols;
 import java.text.NumberFormat;
 import java.time.Duration;
 import java.time.LocalDateTime;
@@ -24,7 +25,7 @@ public final class NumberUtils {
     /**
      * This is our {@link DecimalFormat} for decimal values.
      */
-    private static final DecimalFormat DECIMAL_FORMAT = new DecimalFormat("#.##");
+    private static final DecimalFormat DECIMAL_FORMAT = new DecimalFormat("#.##", DecimalFormatSymbols.getInstance(Locale.ROOT));
 
     /**
      * We do not want any instance of this to be created.
@@ -105,8 +106,31 @@ public final class NumberUtils {
      */
     @Nonnull
     public static String getElapsedTime(@Nonnull LocalDateTime date) {
-        Validate.notNull(date, "Provided date was null");
-        long hours = Duration.between(date, LocalDateTime.now()).toHours();
+        return getElapsedTime(LocalDateTime.now(), date);
+    }
+
+    /**
+     * This returns the elapsed time between the two given {@link LocalDateTime LocalDateTimes}.
+     * The output will be nicely formatted based on the elapsed hours or days between the
+     * given {@link LocalDateTime LocalDateTime}.
+     * 
+     * If a {@link LocalDateTime} from today and yesterday (exactly 24h apart) was passed it
+     * will return {@code "1d"}.
+     * One hour later it will read {@code "1d 1h"}. For values smaller than an hour {@code "< 1h"}
+     * will be returned instead.
+     * 
+     * @param start
+     *            The starting {@link LocalDateTime}.
+     * @param end
+     *            The ending {@link LocalDateTime}.
+     * 
+     * @return The elapsed time as a {@link String}
+     */
+    @Nonnull
+    public static String getElapsedTime(@Nonnull LocalDateTime start, @Nonnull LocalDateTime end) {
+        Validate.notNull(start, "Provided start was null");
+        Validate.notNull(end, "Provided end was null");
+        long hours = Duration.between(start, end).toHours();
 
         if (hours == 0) {
             return "< 1h";
@@ -133,12 +157,24 @@ public final class NumberUtils {
         return timeleft + seconds + "s";
     }
 
+    /**
+     * This method parses a {@link String} into an {@link Integer}.
+     * If the {@link String} could not be parsed correctly, the provided
+     * default value will be returned instead.
+     * 
+     * @param str
+     *            The {@link String} to parse
+     * @param defaultValue
+     *            The default value for when the {@link String} could not be parsed
+     * 
+     * @return The resulting {@link Integer}
+     */
     public static int getInt(@Nonnull String str, int defaultValue) {
         if (PatternUtils.NUMERIC.matcher(str).matches()) {
             return Integer.parseInt(str);
+        } else {
+            return defaultValue;
         }
-
-        return defaultValue;
     }
 
     @Nonnull
@@ -183,6 +219,8 @@ public final class NumberUtils {
      *            The value to clamp
      * @param max
      *            The maximum value
+     * 
+     * @return The clamped value
      */
     public static int clamp(int min, int value, int max) {
         if (value < min) {

src/main/java/me/mrCookieSlime/Slimefun/Objects/SlimefunItem/SlimefunItem.java

@@ -84,7 +84,7 @@ public class SlimefunItem implements Placeable {
      * This is a reference to the {@link SlimefunAddon} that registered this
      * {@link SlimefunItem}, if the item has not been registered yet, it will be null.
      */
-    private SlimefunAddon addon;
+    protected SlimefunAddon addon;
 
     /**
      * This is the state of this {@link SlimefunItem}.
@@ -930,6 +930,8 @@ public class SlimefunItem implements Placeable {
      *            The message to send
      */
     public void info(@Nonnull String message) {
+        Validate.notNull(addon, "Cannot log a message for an unregistered item!");
+
         String msg = toString() + ": " + message;
         addon.getLogger().log(Level.INFO, msg);
     }
@@ -943,6 +945,8 @@ public class SlimefunItem implements Placeable {
      *            The message to send
      */
     public void warn(@Nonnull String message) {
+        Validate.notNull(addon, "Cannot send a warning for an unregistered item!");
+
         String msg = toString() + ": " + message;
         addon.getLogger().log(Level.WARNING, msg);
 
@@ -962,6 +966,8 @@ public class SlimefunItem implements Placeable {
      *            The {@link Throwable} to throw as a stacktrace.
      */
     public void error(@Nonnull String message, @Nonnull Throwable throwable) {
+        Validate.notNull(addon, "Cannot send an error for an unregistered item!");
+
         addon.getLogger().log(Level.SEVERE, "Item \"{0}\" from {1} v{2} has caused an Error!", new Object[] { id, addon.getName(), addon.getPluginVersion() });
 
         if (addon.getBugTrackerURL() != null) {

src/main/java/me/mrCookieSlime/Slimefun/Objects/SlimefunItem/abstractItems/AContainer.java

@@ -5,9 +5,12 @@ import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 
+import javax.annotation.Nonnull;
 import javax.annotation.ParametersAreNonnullByDefault;
 
+import org.apache.commons.lang.Validate;
 import org.bukkit.Bukkit;
+import org.bukkit.Location;
 import org.bukkit.Material;
 import org.bukkit.block.Block;
 import org.bukkit.entity.Player;
@@ -17,7 +20,9 @@ import org.bukkit.inventory.ItemStack;
 
 import io.github.thebusybiscuit.cscorelib2.inventory.InvUtils;
 import io.github.thebusybiscuit.cscorelib2.item.CustomItem;
+import io.github.thebusybiscuit.slimefun4.api.SlimefunAddon;
 import io.github.thebusybiscuit.slimefun4.api.events.AsyncMachineProcessCompleteEvent;
+import io.github.thebusybiscuit.slimefun4.api.items.ItemState;
 import io.github.thebusybiscuit.slimefun4.core.attributes.EnergyNetComponent;
 import io.github.thebusybiscuit.slimefun4.core.networks.energy.EnergyNetComponentType;
 import io.github.thebusybiscuit.slimefun4.utils.ChestMenuUtils;
@@ -47,6 +52,10 @@ public abstract class AContainer extends SlimefunItem implements InventoryBlock,
 
     protected final List<MachineRecipe> recipes = new ArrayList<>();
 
+    private int energyConsumedPerTick = -1;
+    private int energyCapacity = -1;
+    private int processingSpeed = -1;
+
     @ParametersAreNonnullByDefault
     public AContainer(Category category, SlimefunItemStack item, RecipeType recipeType, ItemStack[] recipe) {
         super(category, item, recipeType, recipe);
@@ -114,6 +123,7 @@ public abstract class AContainer extends SlimefunItem implements InventoryBlock,
      * 
      * @return The title of the {@link Inventory} of this {@link AContainer}
      */
+    @Nonnull
     public String getInventoryTitle() {
         return getItemName();
     }
@@ -128,12 +138,23 @@ public abstract class AContainer extends SlimefunItem implements InventoryBlock,
      */
     public abstract ItemStack getProgressBar();
 
+    /**
+     * This method returns the max amount of electricity this machine can hold.
+     * 
+     * @return The max amount of electricity this Block can store.
+     */
+    public int getCapacity() {
+        return energyCapacity;
+    }
+
     /**
      * This method returns the amount of energy that is consumed per operation.
      * 
      * @return The rate of energy consumption
      */
-    public abstract int getEnergyConsumption();
+    public int getEnergyConsumption() {
+        return energyConsumedPerTick;
+    }
 
     /**
      * This method returns the speed at which this machine will operate.
@@ -142,7 +163,86 @@ public abstract class AContainer extends SlimefunItem implements InventoryBlock,
      * 
      * @return The speed of this machine
      */
-    public abstract int getSpeed();
+    public int getSpeed() {
+        return processingSpeed;
+    }
+
+    /**
+     * This sets the energy capacity for this machine.
+     * This method <strong>must</strong> be called before registering the item
+     * and only before registering.
+     * 
+     * @param capacity
+     *            The amount of energy this machine can store
+     * 
+     * @return This method will return the current instance of {@link AContainer}, so that can be chained.
+     */
+    public final AContainer setCapacity(int capacity) {
+        Validate.isTrue(capacity > 0, "The capacity must be greater than zero!");
+
+        if (getState() == ItemState.UNREGISTERED) {
+            this.energyCapacity = capacity;
+            return this;
+        } else {
+            throw new IllegalStateException("You cannot modify the capacity after the Item was registered.");
+        }
+    }
+
+    /**
+     * This sets the speed of this machine.
+     * 
+     * @param speed
+     *            The speed multiplier for this machine, must be above zero
+     * 
+     * @return This method will return the current instance of {@link AContainer}, so that can be chained.
+     */
+    public final AContainer setProcessingSpeed(int speed) {
+        Validate.isTrue(speed > 0, "The speed must be greater than zero!");
+
+        this.processingSpeed = speed;
+        return this;
+    }
+
+    /**
+     * This method sets the energy consumed by this machine per tick.
+     * 
+     * @param energyConsumption
+     *            The energy consumed per tick
+     * 
+     * @return This method will return the current instance of {@link AContainer}, so that can be chained.
+     */
+    public final AContainer setEnergyConsumption(int energyConsumption) {
+        Validate.isTrue(energyConsumption > 0, "The energy consumption must be greater than zero!");
+        Validate.isTrue(energyCapacity > 0, "You must specify the capacity before you can set the consumption amount.");
+        Validate.isTrue(energyConsumption <= energyCapacity, "The energy consumption cannot be higher than the capacity (" + energyCapacity + ')');
+
+        this.energyConsumedPerTick = energyConsumption;
+        return this;
+    }
+
+    @Override
+    public void register(@Nonnull SlimefunAddon addon) {
+        this.addon = addon;
+
+        if (getCapacity() <= 0) {
+            warn("The capacity has not been configured correctly. The Item was disabled.");
+            warn("Make sure to call '" + getClass().getSimpleName() + "#setEnergyCapacity(...)' before registering!");
+        }
+
+        if (getEnergyConsumption() <= 0) {
+            warn("The energy consumption has not been configured correctly. The Item was disabled.");
+            warn("Make sure to call '" + getClass().getSimpleName() + "#setEnergyConsumption(...)' before registering!");
+        }
+
+        if (getSpeed() <= 0) {
+            warn("The processing speed has not been configured correctly. The Item was disabled.");
+            warn("Make sure to call '" + getClass().getSimpleName() + "#setProcessingSpeed(...)' before registering!");
+        }
+
+        if (getCapacity() > 0 && getEnergyConsumption() > 0 && getSpeed() > 0) {
+            super.register(addon);
+        }
+    }
 
     /**
      * This method returns an internal identifier that is used to identify this {@link AContainer}
@@ -154,6 +254,7 @@ public abstract class AContainer extends SlimefunItem implements InventoryBlock,
      * 
      * @return The identifier of this machine
      */
+    @Nonnull
     public abstract String getMachineIdentifier();
 
     /**
@@ -238,31 +339,30 @@ public abstract class AContainer extends SlimefunItem implements InventoryBlock,
         BlockMenu inv = BlockStorage.getInventory(b);
 
         if (isProcessing(b)) {
-            int timeleft = progress.get(b);
 
-            if (timeleft > 0) {
-                ChestMenuUtils.updateProgressbar(inv, 22, timeleft, processing.get(b).getTicks(), getProgressBar());
+            if (takeCharge(b.getLocation())) {
 
-                if (isChargeable()) {
-                    if (getCharge(b.getLocation()) < getEnergyConsumption()) {
-                        return;
+                int timeleft = progress.get(b);
+
+                if (timeleft > 0) {
+                    ChestMenuUtils.updateProgressbar(inv, 22, timeleft, processing.get(b).getTicks(), getProgressBar());
+
+                    progress.put(b, timeleft - 1);
+                } else {
+
+                    inv.replaceExistingItem(22, new CustomItem(Material.BLACK_STAINED_GLASS_PANE, " "));
+
+                    for (ItemStack output : processing.get(b).getOutput()) {
+                        inv.pushItem(output.clone(), getOutputSlots());
                     }
 
-                    removeCharge(b.getLocation(), getEnergyConsumption());
+                    Bukkit.getPluginManager().callEvent(new AsyncMachineProcessCompleteEvent(b.getLocation(), AContainer.this, getProcessing(b)));
+
+                    progress.remove(b);
+                    processing.remove(b);
                 }
-                progress.put(b, timeleft - 1);
-            } else {
-                inv.replaceExistingItem(22, new CustomItem(Material.BLACK_STAINED_GLASS_PANE, " "));
-
-                for (ItemStack output : processing.get(b).getOutput()) {
-                    inv.pushItem(output.clone(), getOutputSlots());
-                }
-
-                Bukkit.getPluginManager().callEvent(new AsyncMachineProcessCompleteEvent(b.getLocation(), AContainer.this, getProcessing(b)));
-
-                progress.remove(b);
-                processing.remove(b);
             }
+
         } else {
             MachineRecipe next = findNextRecipe(inv);
 
@@ -273,6 +373,28 @@ public abstract class AContainer extends SlimefunItem implements InventoryBlock,
         }
     }
 
+    /**
+     * This method will remove charge from a location if it is chargeable.
+     *
+     * @param l
+     *            location to try to remove charge from
+     * @return Whether charge was taken if its chargeable
+     */
+    protected boolean takeCharge(@Nonnull Location l) {
+        Validate.notNull(l, "Can't attempt to take charge from a null location!");
+
+        if (isChargeable()) {
+            if (getCharge(l) < getEnergyConsumption()) {
+                return false;
+            }
+
+            removeCharge(l, getEnergyConsumption());
+            return true;
+        } else {
+            return true;
+        }
+    }
+
     protected MachineRecipe findNextRecipe(BlockMenu inv) {
         Map<Integer, ItemStack> inventory = new HashMap<>();
 

src/main/java/me/mrCookieSlime/Slimefun/Objects/SlimefunItem/abstractItems/AGenerator.java

@@ -3,8 +3,11 @@ package me.mrCookieSlime.Slimefun.Objects.SlimefunItem.abstractItems;
 import java.util.HashMap;
 import java.util.Map;
 
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
 import javax.annotation.ParametersAreNonnullByDefault;
 
+import org.apache.commons.lang.Validate;
 import org.bukkit.Bukkit;
 import org.bukkit.Location;
 import org.bukkit.Material;
@@ -15,7 +18,9 @@ import org.bukkit.inventory.ItemStack;
 
 import io.github.thebusybiscuit.cscorelib2.item.CustomItem;
 import io.github.thebusybiscuit.cscorelib2.protection.ProtectableAction;
+import io.github.thebusybiscuit.slimefun4.api.SlimefunAddon;
 import io.github.thebusybiscuit.slimefun4.api.events.AsyncGeneratorProcessCompleteEvent;
+import io.github.thebusybiscuit.slimefun4.api.items.ItemState;
 import io.github.thebusybiscuit.slimefun4.implementation.SlimefunItems;
 import io.github.thebusybiscuit.slimefun4.implementation.SlimefunPlugin;
 import io.github.thebusybiscuit.slimefun4.implementation.items.electric.AbstractEnergyProvider;
@@ -42,6 +47,9 @@ public abstract class AGenerator extends AbstractEnergyProvider {
     private static final int[] border_in = { 9, 10, 11, 12, 18, 21, 27, 28, 29, 30 };
     private static final int[] border_out = { 14, 15, 16, 17, 23, 26, 32, 33, 34, 35 };
 
+    private int energyProducedPerTick = -1;
+    private int energyCapacity = -1;
+
     @ParametersAreNonnullByDefault
     public AGenerator(Category category, SlimefunItemStack item, RecipeType recipeType, ItemStack[] recipe) {
         super(category, item, recipeType, recipe);
@@ -188,7 +196,7 @@ public abstract class AGenerator extends AbstractEnergyProvider {
         }
     }
 
-    private boolean isBucket(ItemStack item) {
+    private boolean isBucket(@Nullable ItemStack item) {
         if (item == null) {
             return false;
         }
@@ -210,4 +218,78 @@ public abstract class AGenerator extends AbstractEnergyProvider {
         return null;
     }
 
+    /**
+     * This method returns the max amount of electricity this machine can hold.
+     * 
+     * @return The max amount of electricity this Block can store.
+     */
+    public int getCapacity() {
+        return energyCapacity;
+    }
+
+    /**
+     * This method returns the amount of energy that is consumed per operation.
+     * 
+     * @return The rate of energy consumption
+     */
+    @Override
+    public int getEnergyProduction() {
+        return energyProducedPerTick;
+    }
+
+    /**
+     * This sets the energy capacity for this machine.
+     * This method <strong>must</strong> be called before registering the item
+     * and only before registering.
+     * 
+     * @param capacity
+     *            The amount of energy this machine can store
+     * 
+     * @return This method will return the current instance of {@link AGenerator}, so that can be chained.
+     */
+    public final AGenerator setCapacity(int capacity) {
+        Validate.isTrue(capacity >= 0, "The capacity cannot be negative!");
+
+        if (getState() == ItemState.UNREGISTERED) {
+            this.energyCapacity = capacity;
+            return this;
+        } else {
+            throw new IllegalStateException("You cannot modify the capacity after the Item was registered.");
+        }
+    }
+
+    /**
+     * This method sets the energy produced by this machine per tick.
+     * 
+     * @param energyProduced
+     *            The energy produced per tick
+     * 
+     * @return This method will return the current instance of {@link AGenerator}, so that can be chained.
+     */
+    public final AGenerator setEnergyProduction(int energyProduced) {
+        Validate.isTrue(energyProduced > 0, "The energy production must be greater than zero!");
+
+        this.energyProducedPerTick = energyProduced;
+        return this;
+    }
+
+    @Override
+    public void register(@Nonnull SlimefunAddon addon) {
+        this.addon = addon;
+
+        if (getCapacity() < 0) {
+            warn("The capacity has not been configured correctly. The Item was disabled.");
+            warn("Make sure to call '" + getClass().getSimpleName() + "#setEnergyCapacity(...)' before registering!");
+        }
+
+        if (getEnergyProduction() <= 0) {
+            warn("The energy consumption has not been configured correctly. The Item was disabled.");
+            warn("Make sure to call '" + getClass().getSimpleName() + "#setEnergyProduction(...)' before registering!");
+        }
+
+        if (getCapacity() >= 0 && getEnergyProduction() > 0) {
+            super.register(addon);
+        }
+    }
+
 }

src/main/java/me/mrCookieSlime/Slimefun/Objects/SlimefunItem/interfaces/InventoryBlock.java

@@ -19,7 +19,7 @@ import me.mrCookieSlime.Slimefun.api.item_transport.ItemTransportFlow;
  * @deprecated This interface is not designed to be used by addons.
  *
  */
-// @Deprecated - commented out because we are not ready to send out warnings yet
+@Deprecated
 public interface InventoryBlock {
 
     /**

src/main/java/me/mrCookieSlime/Slimefun/api/inventory/BlockMenuPreset.java

@@ -15,6 +15,7 @@ import org.bukkit.inventory.InventoryView;
 import org.bukkit.inventory.ItemStack;
 
 import io.github.thebusybiscuit.slimefun4.implementation.SlimefunPlugin;
+import io.github.thebusybiscuit.slimefun4.utils.ChestMenuUtils;
 import me.mrCookieSlime.CSCoreLibPlugin.general.Inventory.ChestMenu;
 import me.mrCookieSlime.Slimefun.Objects.SlimefunItem.SlimefunItem;
 import me.mrCookieSlime.Slimefun.api.item_transport.ItemTransportFlow;
@@ -122,6 +123,33 @@ public abstract class BlockMenuPreset extends ChestMenu {
         throw new UnsupportedOperationException("BlockMenuPreset does not support this method.");
     }
 
+    /**
+     * This method will draw unclickable background items into this {@link BlockMenuPreset}.
+     * 
+     * @param item
+     *            The {@link ItemStack} that should be used as background
+     * @param slots
+     *            The slots which should be treated as background
+     */
+    public void drawBackground(@Nonnull ItemStack item, @Nonnull int[] slots) {
+        Validate.notNull(item, "The background item cannot be null!");
+        checkIfLocked();
+
+        for (int slot : slots) {
+            addItem(slot, item, ChestMenuUtils.getEmptyClickHandler());
+        }
+    }
+
+    /**
+     * This method will draw unclickable background items into this {@link BlockMenuPreset}.
+     * 
+     * @param slots
+     *            The slots which should be treated as background
+     */
+    public void drawBackground(@Nonnull int[] slots) {
+        drawBackground(ChestMenuUtils.getBackground(), slots);
+    }
+
     @Override
     public ChestMenu addItem(int slot, @Nullable ItemStack item) {
         checkIfLocked();

src/main/resources/config.yml

@@ -37,6 +37,7 @@ URID:
 networks:
   max-size: 200
   cargo-ticker-delay: 0
+  enable-visualizer: true
 
 items:
   talismans: true

src/main/resources/languages/categories_zh-TW.yml

@@ -6,7 +6,7 @@ slimefun:
   food: 食物
   basic_machines: 基礎機器
   electricity: 電力與能源
-  gps: GPS機械
+  gps: GPS 機械
   armor: 盔甲
   magical_items: 魔法物品
   magical_gadgets: 魔法工具
@@ -16,11 +16,11 @@ slimefun:
   cargo: 物流管理
   tech_misc: 科技組件
   magical_armor: 魔法盔甲
-  talismans: 護符(初級)
-  ender_talismans: 護符(終界)
+  talismans: 護符（初級）
+  ender_talismans: 護符（終界）
   christmas: 聖誕節
   valentines_day: 西洋情人節
   easter: 復活節
-  birthday: TheBusyBiscuit的生日(10月26日)
+  birthday: TheBusyBiscuit 的生日(10 月 26 日)
   halloween: 萬聖節
   androids: 可編輯的機器人

src/main/resources/languages/messages_ar.yml

@@ -245,9 +245,9 @@ messages:
   no-tome-yourself: "&cلا يمكنك إستعمال &4القاموس &cعلى نفسك..."
   not-online: "&4%player% &cغير متصل!"
   not-researched: "&4لا تملك خبرة لفهم هذا الأمر"
-  not-valid-amount: "&4%amount% &cليست قيمة صحيحة: يجب أن تكون أكثر من صفر!"
-  not-valid-item: "&4%item% &cليس عنصر صحيح!"
-  not-valid-research: "&4%research% &cليس بحث صحيح!"
+  invalid-amount: "&4%amount% &cليست قيمة صحيحة: يجب أن تكون أكثر من صفر!"
+  invalid-item: "&4%item% &cليس عنصر صحيح!"
+  invalid-research: "&4%research% &cليس بحث صحيح!"
   only-players: "&4هذا الأمر لللاعبين فقط"
   opening-backpack: "&bيتم فتح الحقيبة، قد تستغرق ثوان..."
   opening-guide: "&bيتم فتح الكتيب، قد يستغرق ثوان..."

src/main/resources/languages/messages_cs.yml

@@ -100,11 +100,11 @@ messages:
   no-permission: "&4Na tohle nemáš dostatečné povolení"
   usage: "&4Použití: &c%usage%"
   not-online: "&4%player% &czrovna není připojen!"
-  not-valid-item: "&4%item% &cnení platný item!"
-  not-valid-amount: "&4%amount% &cnení platné číslo : musí být větší než 0!"
+  invalid-item: "&4%item% &cnení platný item!"
+  invalid-amount: "&4%amount% &cnení platné číslo : musí být větší než 0!"
   given-item: '&bDostal jsi &a%amount% &7"%item%&7"'
   give-item: '&bDal jsi %player% &a%amount% &7"%item%&7"'
-  not-valid-research: "&4%research% &cnení platný výzkum!"
+  invalid-research: "&4%research% &cnení platný výzkum!"
   give-research: '&bUdělil jsi %player% výzkum  &7"%research%&7"'
   hungry: "&cJsi moc hladový na to, abys to zvládl!"
   disabled-in-world: "&4&lTahle věc není v tomhle světě povolená"

src/main/resources/languages/messages_de.yml

@@ -108,11 +108,11 @@ messages:
   no-permission: "&4Du hast nicht die benötigten Rechte hierfür"
   usage: "&4Korrekte Schreibweise: &c%usage%"
   not-online: "&4%player% &cist derzeit nicht online!"
-  not-valid-item: "&4%item% &cist kein gültiges Item!"
-  not-valid-amount: "&4%amount% &cist keine gültige Anzahl! Sie muss höher als 0 sein!"
+  invalid-item: "&4%item% &cist kein gültiges Item!"
+  invalid-amount: "&4%amount% &cist keine gültige Anzahl! Sie muss höher als 0 sein!"
   given-item: '&bDir wurde &a%amount% &7mal "%item%&7" gegeben'
   give-item: '&bDu hast %player% &a%amount% &7"%item%&7" gegeben'
-  not-valid-research: "&4%research% &cist kein gültiger Erfahrungsgrad!"
+  invalid-research: "&4%research% &cist kein gültiger Erfahrungsgrad!"
   give-research: '&bDu hast %player% den Erfahrungsgrad &7"%research%&7" vergeben'
   hungry: "&cDu bist zu hungrig, um dies zu tun!"
   disabled-in-world: "&4&lDieses Item wurde in dieser Welt deaktiviert!"