From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Tue, 16 Jul 2013 21:26:50 -0400
Subject: [PATCH] Add MetadataStoreBase.removeAll(Plugin)

So that on reload, metadata will be cleared

diff --git a/src/main/java/org/bukkit/metadata/MetadataStoreBase.java b/src/main/java/org/bukkit/metadata/MetadataStoreBase.java
index a0698522f01619c9d37474f4bd55a17de58fff89..a298baaa7a126515bb2802dd311f8487f3e5533f 100644
--- a/src/main/java/org/bukkit/metadata/MetadataStoreBase.java
+++ b/src/main/java/org/bukkit/metadata/MetadataStoreBase.java
@@ -5,6 +5,7 @@ import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.HashMap;
+import java.util.Iterator; // Paper
 import java.util.List;
 import java.util.Map;
 import java.util.WeakHashMap;
@@ -130,6 +131,26 @@ public abstract class MetadataStoreBase<T> {
         }
     }
 
+    /**
+     * Removes all metadata in the metadata store that originates from the
+     * given plugin.
+     *
+     * @param owningPlugin the plugin requesting the invalidation.
+     * @throws IllegalArgumentException If plugin is null
+     */
+    public void removeAll(@NotNull Plugin owningPlugin) {
+        Preconditions.checkNotNull(owningPlugin, "Plugin cannot be null");
+        for (Iterator<Map<Plugin, MetadataValue>> iterator = metadataMap.values().iterator(); iterator.hasNext(); ) {
+            Map<Plugin, MetadataValue> values = iterator.next();
+            if (values.containsKey(owningPlugin)) {
+                values.remove(owningPlugin);
+            }
+            if (values.isEmpty()) {
+                iterator.remove();
+            }
+        }
+    }
+
     /**
      * Creates a unique name for the object receiving metadata by combining
      * unique data from the subject with a metadataKey.