Deprecate and stop using Java15Compat class.

By: md_5 <git@md-5.net>

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

@@ -1,6 +1,7 @@
 package org.bukkit;
 
 import java.lang.reflect.Constructor;
+import java.util.Arrays;
 import java.util.Map;
 
 import org.apache.commons.lang.Validate;
@@ -58,8 +59,6 @@ import org.bukkit.material.Vine;
 import org.bukkit.material.Wood;
 import org.bukkit.material.WoodenStep;
 import org.bukkit.material.Wool;
-import org.bukkit.potion.Potion;
-import org.bukkit.util.Java15Compat;
 
 import com.google.common.collect.Maps;
 
@@ -721,7 +720,7 @@ public enum Material {
             if (byId.length > material.id) {
                 byId[material.id] = material;
             } else {
-                byId = Java15Compat.Arrays_copyOfRange(byId, 0, material.id + 2);
+                byId = Arrays.copyOfRange(byId, 0, material.id + 2);
                 byId[material.id] = material;
             }
             BY_NAME.put(material.name(), material);

paper-api/src/main/java/org/bukkit/command/SimpleCommandMap.java

@@ -1,8 +1,7 @@
 package org.bukkit.command;
 
-import static org.bukkit.util.Java15Compat.Arrays_copyOfRange;
-
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.HashMap;
@@ -137,7 +136,7 @@ public class SimpleCommandMap implements CommandMap {
 
         try {
             // Note: we don't return the result of target.execute as thats success / failure, we return handled (true) or not handled (false)
-            target.execute(sender, sentCommandLabel, Arrays_copyOfRange(args, 1, args.length));
+            target.execute(sender, sentCommandLabel, Arrays.copyOfRange(args, 1, args.length));
         } catch (CommandException ex) {
             throw ex;
         } catch (Throwable ex) {

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

@@ -2,6 +2,7 @@ package org.bukkit.util;
 
 import org.bukkit.ChatColor;
 
+import java.util.Arrays;
 import java.util.LinkedList;
 import java.util.List;
 
@@ -46,7 +47,7 @@ public class ChatPaginator {
 
         int from = (actualPageNumber - 1) * pageHeight;
         int to = from + pageHeight <= lines.length  ? from + pageHeight : lines.length;
-        String[] selectedLines = Java15Compat.Arrays_copyOfRange(lines, from, to);
+        String[] selectedLines = Arrays.copyOfRange(lines, from, to);
 
         return new ChatPage(selectedLines, actualPageNumber, totalPages);
     }

paper-api/src/main/java/org/bukkit/util/Java15Compat.java

@@ -2,6 +2,11 @@ package org.bukkit.util;
 
 import java.lang.reflect.Array;
 
+/**
+ * @deprecated Bukkit targets Java 1.6. This class will be removed in a
+ * subsequent release.
+ */
+@Deprecated
 public class Java15Compat {
     @SuppressWarnings("unchecked")
     public static <T> T[] Arrays_copyOfRange(T[] original, int start, int end) {