Solved I broke NMS.. (Hooray?)

Trying to make a reflectionized method for auto-respawning in 1.7.2 and it seems I have broken NMS. I made it throw a net.minecraft.util.io.netty.handler.codec.EncoderException, I know right? Amazing.

Code:

kreashenz lost connection: Internal Exception: net.minecraft.util.io.netty.handler.codec.EncoderException: java.io.IOException: Can't serialize unregistered packet

My code

Code:java

    private void reflectionRespawnPlayer(final Player p){
        new BukkitRunnable(){
            public void run(){
                try {
                    Object nmsPlayer = p.getClass().getMethod("getHandle").invoke(p);
                    Object packet = Class.forName(nmsPlayer.getClass().getPackage().getName() + ".PacketPlayInClientCommand").newInstance();
                    Class<?> enumClass = Class.forName(nmsPlayer.getClass().getPackage().getName() + ".EnumClientCommand");
 
                    for(Object ob : enumClass.getEnumConstants()){
                        if(ob.toString().equals("PERFORM_RESPAWN")){
                            packet.getClass().getConstructor(enumClass).newInstance(ob);
                        }
                    }
 
                    Object con = nmsPlayer.getClass().getDeclaredField("playerConnection").get(nmsPlayer);
                    con.getClass().getMethod("sendPacket", Class.forName(nmsPlayer.getClass().getPackage().getName() + ".Packet")).invoke(con, packet);
                }
                catch(Throwable t){
                    t.printStackTrace();
                }
            }
        }.runTaskLater(this, 2L);
    }
 

Any ideas on what the hell has happened, or should I be posting this somewhere else? Thanks!

 

https://github.com/Bukkit/CraftBukk.../minecraft/server/PlayerConnection.java#L1087

Use that. I'm half asleep and have no idea why it works, but I tested it (with nms, not reflection) and it worked.

For the record, all it looks like it's doing is this:

Code:java

this.player = this.minecraftServer.getPlayerList().moveToWorld(this.player, 0, false);

So maybe sending the client a packet isn't necessary anymore? I have no idea, too tired to reverse engineer further, but play around with it.

 

Garris0n I'm using this now

Code:java

con.getClass().getMethod("a", packet.getClass()).invoke(con, packet); // line 46

And this is the error I get

Code:

[14:29:40 WARN]: java.lang.reflect.InvocationTargetException
[14:29:40 WARN]:        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
[14:29:40 WARN]:        at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
[14:29:40 WARN]:        at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
[14:29:40 WARN]:        at java.lang.reflect.Method.invoke(Unknown Source)
[14:29:40 WARN]:        at me.kreashenz.test.Main$2.run(Main.java:46)
[14:29:40 WARN]:        at org.bukkit.craftbukkit.v1_7_R1.scheduler.CraftTask.run(CraftTask.java:53)
[14:29:40 WARN]:        at org.bukkit.craftbukkit.v1_7_R1.scheduler.CraftScheduler.mainThreadHeartbeat(CraftScheduler.java:345)
[14:29:40 WARN]:        at net.minecraft.server.v1_7_R1.MinecraftServer.u(MinecraftServer.java:583)
[14:29:40 WARN]:        at net.minecraft.server.v1_7_R1.DedicatedServer.u(DedicatedServer.java:250)
[14:29:40 WARN]:        at net.minecraft.server.v1_7_R1.MinecraftServer.t(MinecraftServer.java:541)
[14:29:40 WARN]:        at net.minecraft.server.v1_7_R1.MinecraftServer.run(MinecraftServer.java:453)
[14:29:40 WARN]:        at net.minecraft.server.v1_7_R1.ThreadServerApplication.run(SourceFile:617)
[14:29:40 WARN]: Caused by: java.lang.NullPointerException
[14:29:40 WARN]:        at net.minecraft.server.v1_7_R1.PlayerConnection.a(PlayerConnection.java:1091)
[14:29:40 WARN]:        ... 12 more

 

I don't know much about reflection (and I'm half asleep) but the issue is that .c() is returning null. The actual issue appeared to be that

Code:java

packet.getClass().getConstructor(enumClass).newInstance(ob);

Should be

Code:java

packet = packet.getClass().getConstructor(enumClass).newInstance(ob);

Appears to work for me.

 

Garris0n Hooray, it works! Thanks man