Remove KeyedObject interface (#7680)

patches/server/0088-remove-null-possibility-for-getServer-singleton.patch

@@ -0,0 +1,36 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: Aikar <aikar@aikar.co>
+Date: Thu, 28 Apr 2016 00:57:27 -0400
+Subject: [PATCH] remove null possibility for getServer singleton
+
+to stop IDE complaining about potential NPE
+
+diff --git a/src/main/java/net/minecraft/server/MinecraftServer.java b/src/main/java/net/minecraft/server/MinecraftServer.java
+index 66ba45e0a3c4970df9f8b3a0b8b5cfdaf597e40c..9e95cb40ce6839de2582e71576b73cdf8787a042 100644
+--- a/src/main/java/net/minecraft/server/MinecraftServer.java
++++ b/src/main/java/net/minecraft/server/MinecraftServer.java
+@@ -185,6 +185,7 @@ import co.aikar.timings.MinecraftTimings; // Paper
+ 
+ public abstract class MinecraftServer extends ReentrantBlockableEventLoop<TickTask> implements CommandSource, AutoCloseable {
+ 
++    private static MinecraftServer SERVER; // Paper
+     public static final Logger LOGGER = LogUtils.getLogger();
+     public static final String VANILLA_BRAND = "vanilla";
+     private static final float AVERAGE_TICK_TIME_SMOOTHING = 0.8F;
+@@ -319,6 +320,7 @@ public abstract class MinecraftServer extends ReentrantBlockableEventLoop<TickTa
+ 
+     public MinecraftServer(OptionSet options, DataPackConfig datapackconfiguration, DynamicOps<Tag> registryreadops, Thread thread, LevelStorageSource.LevelStorageAccess convertable_conversionsession, PackRepository resourcepackrepository, WorldStem worldstem, Proxy proxy, DataFixer datafixer, @Nullable MinecraftSessionService minecraftsessionservice, @Nullable GameProfileRepository gameprofilerepository, @Nullable GameProfileCache usercache, ChunkProgressListenerFactory worldloadlistenerfactory) {
+         super("Server");
++        SERVER = this; // Paper - better singleton
+         this.metricsRecorder = InactiveMetricsRecorder.INSTANCE;
+         this.profiler = this.metricsRecorder.getProfiler();
+         this.onMetricsRecordingStopped = (methodprofilerresults) -> {
+@@ -2306,7 +2308,7 @@ public abstract class MinecraftServer extends ReentrantBlockableEventLoop<TickTa
+ 
+     @Deprecated
+     public static MinecraftServer getServer() {
+-        return (Bukkit.getServer() instanceof CraftServer) ? ((CraftServer) Bukkit.getServer()).getServer() : null;
++        return SERVER; // Paper
+     }
+     // CraftBukkit end
+