Use thread groups to detect the effective side (#3644)

src/main/java/net/minecraftforge/fml/common/FMLCommonHandler.java

@@ -64,6 +64,8 @@ import net.minecraftforge.fml.common.gameevent.PlayerEvent;
 import net.minecraftforge.fml.common.gameevent.TickEvent;
 import net.minecraftforge.fml.common.gameevent.TickEvent.Phase;
 import net.minecraftforge.fml.common.network.NetworkRegistry;
+import net.minecraftforge.fml.common.thread.SidedThreadGroup;
+import net.minecraftforge.fml.common.thread.SidedThreadGroups;
 import net.minecraftforge.fml.relauncher.CoreModManager;
 import net.minecraftforge.fml.relauncher.Side;
 import net.minecraftforge.fml.server.FMLServerHandler;
@@ -201,13 +203,8 @@ public class FMLCommonHandler
      */
     public Side getEffectiveSide()
     {
-        Thread thr = Thread.currentThread();
-        if (thr.getName().equals("Server thread") || thr.getName().startsWith("Netty Server IO"))
-        {
-            return Side.SERVER;
-        }
-
-        return Side.CLIENT;
+        final ThreadGroup group = Thread.currentThread().getThreadGroup();
+        return group instanceof SidedThreadGroup ? ((SidedThreadGroup) group).getSide() : Side.CLIENT;
     }
     /**
      * Raise an exception

src/main/java/net/minecraftforge/fml/common/thread/SidedThreadGroup.java

@@ -0,0 +1,56 @@
+/*
+ * Minecraft Forge
+ * Copyright (c) 2016.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation version 2.1
+ * of the License.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+package net.minecraftforge.fml.common.thread;
+
+import net.minecraftforge.fml.relauncher.Side;
+
+import java.util.concurrent.ThreadFactory;
+
+import javax.annotation.Nonnull;
+
+/**
+ * A thread group and factory combination which belongs to a {@link Side}.
+ */
+public final class SidedThreadGroup extends ThreadGroup implements ThreadFactory
+{
+    private final Side side;
+
+    SidedThreadGroup(final Side side)
+    {
+        super(side.name());
+        this.side = side;
+    }
+
+    /**
+     * Gets the side this sided thread group belongs to.
+     *
+     * @return the side
+     */
+    public Side getSide()
+    {
+        return this.side;
+    }
+
+    @Override
+    public Thread newThread(@Nonnull final Runnable runnable)
+    {
+        return new Thread(this, runnable);
+    }
+}

src/main/java/net/minecraftforge/fml/common/thread/SidedThreadGroups.java

@@ -0,0 +1,31 @@
+/*
+ * Minecraft Forge
+ * Copyright (c) 2016.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation version 2.1
+ * of the License.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+package net.minecraftforge.fml.common.thread;
+
+import net.minecraftforge.fml.relauncher.Side;
+
+public final class SidedThreadGroups
+{
+    public static final SidedThreadGroup CLIENT = new SidedThreadGroup(Side.CLIENT);
+    public static final SidedThreadGroup SERVER = new SidedThreadGroup(Side.SERVER);
+
+    private SidedThreadGroups() {
+    }
+}