#898: Use Java Consumer instead of Bukkit Consumer

By: DerFrZocker <derrieple@gmail.com>

paper-api/src/main/java/org/bukkit/RegionAccessor.java

@@ -3,6 +3,7 @@ package org.bukkit;
 import java.util.Collection;
 import java.util.List;
 import java.util.Random;
+import java.util.function.Consumer;
 import java.util.function.Predicate;
 import org.bukkit.block.Biome;
 import org.bukkit.block.BlockState;
@@ -10,7 +11,6 @@ import org.bukkit.block.data.BlockData;
 import org.bukkit.entity.Entity;
 import org.bukkit.entity.EntityType;
 import org.bukkit.entity.LivingEntity;
-import org.bukkit.util.Consumer;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 

paper-api/src/main/java/org/bukkit/World.java

@@ -6,6 +6,7 @@ import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
+import java.util.function.Consumer;
 import java.util.function.Predicate;
 import org.bukkit.block.Biome;
 import org.bukkit.block.Block;
@@ -33,7 +34,6 @@ import org.bukkit.persistence.PersistentDataHolder;
 import org.bukkit.plugin.Plugin;
 import org.bukkit.plugin.messaging.PluginMessageRecipient;
 import org.bukkit.util.BoundingBox;
-import org.bukkit.util.Consumer;
 import org.bukkit.util.RayTraceResult;
 import org.bukkit.util.StructureSearchResult;
 import org.bukkit.util.Vector;
@@ -521,7 +521,7 @@ public interface World extends RegionAccessor, WorldInfo, PluginMessageRecipient
      * @param delegate A class to call for each block changed as a result of
      *     this method
      * @return true if the tree was created successfully, otherwise false
-     * @see #generateTree(org.bukkit.Location, java.util.Random, org.bukkit.TreeType, org.bukkit.util.Consumer)
+     * @see #generateTree(org.bukkit.Location, java.util.Random, org.bukkit.TreeType, java.util.function.Consumer)
      * @deprecated this method does not handle tile entities (bee nests)
      */
     @Deprecated

paper-api/src/main/java/org/bukkit/util/Consumer.java

@@ -5,13 +5,19 @@ package org.bukkit.util;
  * result.
  *
  * @param <T> the type of the input to the operation
+ * @deprecated Use {@link java.util.function.Consumer} instead
  */
-public interface Consumer<T> {
+// Bukkit developer note (NOT plugin developers):
+// NEVER use this consumer in the API.
+// API methods which use this consumer will be remapped to Java's consumer at runtime, resulting in an error.
+@Deprecated
+public interface Consumer<T> extends java.util.function.Consumer<T> {
 
     /**
      * Performs this operation on the given argument.
      *
      * @param t the input argument
      */
+    @Override
     void accept(T t);
 }