feat(function): 添加 andThen 与 compose 方法

。

api/src/main/java/cc/carm/lib/easysql/api/action/PreparedSQLUpdateAction.java

@@ -17,6 +17,7 @@ public interface PreparedSQLUpdateAction<T extends Number> extends SQLUpdateActi
      *
      * @param params 参数内容
      * @return {@link PreparedSQLUpdateAction}
+     * @since 0.4.0
      */
     PreparedSQLUpdateAction<T> setParams(@Nullable Iterable<Object> params);
 

api/src/main/java/cc/carm/lib/easysql/api/action/PreparedSQLUpdateBatchAction.java

@@ -35,6 +35,7 @@ public interface PreparedSQLUpdateBatchAction<T extends Number> extends SQLActio
      * @param keyTypeClass 自增序列的数字类型
      * @param <N>          自增键序列类型 {@link Number}
      * @return {@link SQLUpdateAction}
+     * @since 0.4.0
      */
     <N extends Number> PreparedSQLUpdateBatchAction<N> returnGeneratedKeys(Class<N> keyTypeClass);
 

api/src/main/java/cc/carm/lib/easysql/api/action/SQLUpdateAction.java

@@ -18,6 +18,7 @@ public interface SQLUpdateAction<T extends Number> extends SQLAction<T> {
      * @param keyTypeClass 自增序列的数字类型
      * @param <N>          自增键序列类型 {@link Number}
      * @return {@link SQLUpdateAction}
+     * @since 0.4.0
      */
     <N extends Number> SQLUpdateAction<N> returnGeneratedKey(Class<N> keyTypeClass);
 

api/src/main/java/cc/carm/lib/easysql/api/function/SQLFunction.java

@@ -4,6 +4,7 @@ import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
 import java.sql.SQLException;
+import java.util.Objects;
 
 @FunctionalInterface
 public interface SQLFunction<T, R> {
@@ -11,4 +12,23 @@ public interface SQLFunction<T, R> {
     @Nullable
     R apply(@NotNull T t) throws SQLException;
 
+    default <V> SQLFunction<V, R> compose(@NotNull SQLFunction<? super V, ? extends T> before) {
+        Objects.requireNonNull(before);
+        return (V v) -> {
+            T t = before.apply(v);
+            if (t == null) return null;
+            else return apply(t);
+        };
+    }
+
+    default <V> SQLFunction<T, V> then(@NotNull SQLFunction<? super R, ? extends V> after) {
+        Objects.requireNonNull(after);
+        return (T t) -> {
+            R r = apply(t);
+            if (r == null) return null;
+            else return after.apply(r);
+        };
+    }
+
+
 }