feat: A lightweight JSON serializer

src/main/java/cc/carm/lib/bukkit/configuration/BukkitJSONSerializer.java

@@ -0,0 +1,162 @@
+package cc.carm.lib.bukkit.configuration;
+
+import com.google.gson.Gson;
+import com.google.gson.GsonBuilder;
+import com.google.gson.JsonObject;
+import com.google.gson.JsonParser;
+import org.bukkit.configuration.serialization.ConfigurationSerializable;
+import org.bukkit.configuration.serialization.ConfigurationSerialization;
+import org.jetbrains.annotations.Contract;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.LinkedHashMap;
+import java.util.Map;
+import java.util.Optional;
+
+/**
+ * BukkitJSONSerializer, a lightweight JSON serializer for {@link ConfigurationSerializable} objects.
+ * <li>serialize by {@link #serializeToJSON(ConfigurationSerializable)}</li>
+ * <li>deserialize by {@link #deserializeJSON(String, Class, ConfigurationSerializable)}</li>
+ *
+ * @author CarmJos
+ * @since 1.0.0
+ */
+public class BukkitJSONSerializer {
+
+    protected static final String TYPE_KEY = ConfigurationSerialization.SERIALIZED_TYPE_KEY;
+
+    protected static Gson gson = new GsonBuilder().disableHtmlEscaping().create();
+    protected static JsonParser parser = new JsonParser();
+
+    public static void setGson(Gson gson) {
+        BukkitJSONSerializer.gson = gson;
+    }
+
+    public static void setParser(JsonParser parser) {
+        BukkitJSONSerializer.parser = parser;
+    }
+
+    /**
+     * Serializes a {@link ConfigurationSerializable} object to Map.
+     *
+     * @param value object to serialize.
+     * @param <T>   {@link ConfigurationSerializable} object type.
+     * @return Map containing serialized data
+     */
+    public static <T extends ConfigurationSerializable> Map<String, Object> serializeToMap(T value) {
+        Map<String, Object> values = new LinkedHashMap<>();
+        // First, put tye type key;
+        values.put(TYPE_KEY, ConfigurationSerialization.getAlias(value.getClass()));
+        // Then, put the serialized value
+        value.serialize().forEach((key, sub) -> {
+            if (sub instanceof ConfigurationSerializable) {
+                values.put(key, serializeToMap((ConfigurationSerializable) sub));
+            } else {
+                values.put(key, sub);
+            }
+        });
+        return values;
+    }
+
+    /**
+     * Serializes a {@link ConfigurationSerializable} object to JSON.
+     *
+     * @param value object to serialize.
+     * @param <T>   {@link ConfigurationSerializable} object type.
+     * @return JSON string containing serialized data.
+     */
+    public static <T extends ConfigurationSerializable> String serializeToJSON(T value) {
+        return gson.toJson(serializeToMap(value));
+    }
+
+    /**
+     * Deserializes a {@link ConfigurationSerializable} object from JSON.
+     *
+     * @param json JSON string to deserialize.
+     * @return Deserialized object.
+     */
+    @Contract("null->null")
+    public static Object deserializeJSON(@Nullable String json) {
+        return deserializeJSON(json, (ConfigurationSerializable) null);
+    }
+
+    /**
+     * Deserializes a {@link ConfigurationSerializable} object from JSON.
+     *
+     * @param json         JSON string to deserialize.
+     * @param defaultValue default value to return if json is null or failed to deserialize.
+     * @return Deserialized object.
+     */
+    @Contract("_,!null->!null; null,null->null")
+    public static ConfigurationSerializable deserializeJSON(@Nullable String json,
+                                                            @Nullable ConfigurationSerializable defaultValue) {
+        if (json == null) return defaultValue;
+        Map<String, Object> args = jsonToMap(json);
+
+        return Optional.ofNullable((String) args.get(TYPE_KEY))
+                .map(ConfigurationSerialization::getClassByAlias)
+                .map(clazz -> ConfigurationSerialization.deserializeObject(args, clazz))
+                .orElse(defaultValue);
+    }
+
+    /**
+     * Deserializes a {@link ConfigurationSerializable} object from Map.
+     *
+     * @param json      JSON string to deserialize.
+     * @param typeClazz type of object.
+     * @param <T>       {@link ConfigurationSerializable} object type.
+     * @return Deserialized object.
+     */
+    public static <T extends ConfigurationSerializable> @Nullable T deserializeJSON(@Nullable String json,
+                                                                                    @NotNull Class<T> typeClazz) {
+        return deserializeJSON(json, typeClazz, null);
+    }
+
+    /**
+     * Deserializes a {@link ConfigurationSerializable} object from Map.
+     *
+     * @param json         JSON string to deserialize.
+     * @param typeClazz    type of object.
+     * @param defaultValue default value to return if json is null or failed to deserialize.
+     * @param <T>          {@link ConfigurationSerializable} object type.
+     * @return Deserialized object.
+     */
+    @Contract("_,_,!null->!null; null,_,null->null")
+    public static <T extends ConfigurationSerializable> T deserializeJSON(@Nullable String json,
+                                                                          @NotNull Class<T> typeClazz,
+                                                                          @Nullable T defaultValue) {
+        Object value = deserializeJSON(json, defaultValue);
+        if (!typeClazz.isInstance(value)) return defaultValue;
+
+        return typeClazz.cast(value);
+    }
+
+    protected static Map<String, Object> jsonToMap(String json) {
+        return jsonToMap(parser.parse(json).getAsJsonObject());
+    }
+
+    protected static Map<String, Object> jsonToMap(JsonObject object) {
+        return parseMap(gson.fromJson(object, Map.class));
+    }
+
+    protected static Map<String, Object> parseMap(Map<?, ?> map) {
+        Map<String, Object> args = new LinkedHashMap<>();
+        map.forEach((k, v) -> {
+            String key = (String) k;
+            if (v instanceof Map<?, ?>) {
+                Map<String, Object> sub = parseMap((Map<?, ?>) v);
+                if (sub.containsKey(TYPE_KEY)) {
+                    args.put(key, ConfigurationSerialization.deserializeObject(sub));
+                } else {
+                    args.put(key, sub);
+                }
+            } else {
+                args.put(key, v);
+            }
+        });
+        return args;
+    }
+
+
+}

src/main/java/cc/carm/lib/bukkit/configuration/JSONSerializable.java

@@ -0,0 +1,17 @@
+package cc.carm.lib.bukkit.configuration;
+
+import org.bukkit.configuration.serialization.ConfigurationSerializable;
+import org.jetbrains.annotations.NotNull;
+
+public interface JSONSerializable extends ConfigurationSerializable {
+
+    /**
+     * Serialize this object into a JSON string.
+     *
+     * @return JSON string contains serialized data.
+     */
+    default @NotNull String serializeToJSON() {
+        return BukkitJSONSerializer.serializeToJSON(this);
+    }
+
+}

src/test/java/demo.java

@@ -0,0 +1,50 @@
+import cc.carm.lib.bukkit.configuration.BukkitJSONSerializer;
+import cc.carm.lib.bukkit.configuration.JSONSerializable;
+import org.bukkit.Bukkit;
+import org.bukkit.Location;
+
+import java.util.LinkedHashMap;
+import java.util.Map;
+import java.util.UUID;
+
+public class demo {
+
+    public static void demoUsage() {
+
+        Location location = new Location(Bukkit.getWorlds().get(0), -100.5, 100, 105.5);
+
+        String serialized = BukkitJSONSerializer.serializeToJSON(location);
+        // serialized -> {"world":"world","x":-100.5,"y":100,"z":105.5,"yaw":0.0,"pitch":0.0}
+
+        Location deserialized = BukkitJSONSerializer.deserializeJSON(serialized, Location.class);
+
+    }
+
+    public static final class SomeValue implements JSONSerializable {
+
+        long time;
+        UUID uuid;
+
+        public SomeValue(long time, UUID uuid) {
+            this.time = time;
+            this.uuid = uuid;
+        }
+
+        @Override
+        public Map<String, Object> serialize() {
+            Map<String, Object> map = new LinkedHashMap<>();
+            map.put("time", time);
+            map.put("uuid", uuid.toString());
+            return map;
+        }
+
+        public static SomeValue deserialize(Map<String, Object> map) {
+            return new SomeValue(
+                    (long) map.get("time"),
+                    UUID.fromString((String) map.get("uuid"))
+            );
+        }
+
+    }
+
+}