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NoClassDefFoundError: net/minecraft/world/World$2

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Posted

Got this error, is this a Minecraft Bug, a Forge bug or am I doing something wrong?

 

My Block normally works but sometimes I get this error when calling notifyBlocksOfNeighborChange()...

 

 

Description: Exception in server tick loop
java.lang.NoClassDefFoundError: net/minecraft/world/World$2
at net.minecraft.world.World.notifyBlockOfNeighborChange(World.java:820)
at net.minecraft.world.World.notifyBlocksOfNeighborChange(World.java:773)
at tennox.chameleon.TileEntityChameleon.updateMaster(TileEntityChameleon.java:41)
at tennox.chameleon.BlockChameleon.onBlockAdded(BlockChameleon.java:46)
at net.minecraft.world.chunk.Chunk.func_150807_a(Chunk.java:738)
at net.minecraft.world.World.setBlock(World.java:549)
at net.minecraft.item.ItemBlock.placeBlockAt(ItemBlock.java:232)
at net.minecraft.item.ItemBlock.onItemUse(ItemBlock.java:116)
at net.minecraft.item.ItemStack.tryPlaceItemIntoWorld(ItemStack.java:150)
at net.minecraft.server.management.ItemInWorldManager.activateBlockOrUseItem(ItemInWorldManager.java:424)
at net.minecraft.network.NetHandlerPlayServer.processPlayerBlockPlacement(NetHandlerPlayServer.java:596)
at net.minecraft.network.play.client.C08PacketPlayerBlockPlacement.processPacket(C08PacketPlayerBlockPlacement.java:74)
at net.minecraft.network.play.client.C08PacketPlayerBlockPlacement.processPacket(C08PacketPlayerBlockPlacement.java:122)
at net.minecraft.network.NetworkManager.processReceivedPackets(NetworkManager.java:242)
at net.minecraft.network.NetworkSystem.networkTick(NetworkSystem.java:190)
at net.minecraft.server.MinecraftServer.updateTimeLightAndEntities(MinecraftServer.java:763)
at net.minecraft.server.MinecraftServer.tick(MinecraftServer.java:651)
at net.minecraft.server.integrated.IntegratedServer.tick(IntegratedServer.java:120)
at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:530)
at net.minecraft.server.MinecraftServer$2.run(MinecraftServer.java:788)

 

 

I also got this error one time without even touching my mod Block:

 

Description: Exception in server tick loop

java.lang.NoClassDefFoundError: net/minecraft/world/World$2
at net.minecraft.world.World.notifyBlockOfNeighborChange(World.java:820)
at net.minecraft.world.World.notifyBlocksOfNeighborChange(World.java:752)
at net.minecraft.world.World.notifyBlockChange(World.java:713)
at net.minecraft.world.World.setBlock(World.java:563)
at net.minecraft.item.ItemBlock.placeBlockAt(ItemBlock.java:232)
at net.minecraft.item.ItemBlock.onItemUse(ItemBlock.java:116)
at net.minecraft.item.ItemStack.tryPlaceItemIntoWorld(ItemStack.java:150)
at net.minecraft.server.management.ItemInWorldManager.activateBlockOrUseItem(ItemInWorldManager.java:424)
at net.minecraft.network.NetHandlerPlayServer.processPlayerBlockPlacement(NetHandlerPlayServer.java:596)
at net.minecraft.network.play.client.C08PacketPlayerBlockPlacement.processPacket(C08PacketPlayerBlockPlacement.java:74)
at net.minecraft.network.play.client.C08PacketPlayerBlockPlacement.processPacket(C08PacketPlayerBlockPlacement.java:122)
at net.minecraft.network.NetworkManager.processReceivedPackets(NetworkManager.java:242)
at net.minecraft.network.NetworkSystem.networkTick(NetworkSystem.java:190)
at net.minecraft.server.MinecraftServer.updateTimeLightAndEntities(MinecraftServer.java:763)
at net.minecraft.server.MinecraftServer.tick(MinecraftServer.java:651)
at net.minecraft.server.integrated.IntegratedServer.tick(IntegratedServer.java:120)
at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:530)
at net.minecraft.server.MinecraftServer$2.run(MinecraftServer.java:788)

 

 

 

Forge Version: 1.7.2-10.12.0.104

Base classes aren't modified in any way!

(not sure if that's even possible with gradle?)

  • Author

What version of Minecraft/Forge are you using? Also, did you modify the World class?

 

Sorry...

Forge Version: 1.7.2-10.12.0.104

Base classes aren't modified in any way!

(not sure if that's even possible with gradle?)

at tennox.chameleon.TileEntityChameleon.updateMaster(TileEntityChameleon.java:41)

at tennox.chameleon.BlockChameleon.onBlockAdded(BlockChameleon.java:46)

We need to see your code.

  • Author

at tennox.chameleon.TileEntityChameleon.updateMaster(TileEntityChameleon.java:41)

at tennox.chameleon.BlockChameleon.onBlockAdded(BlockChameleon.java:46)

We need to see your code.

 

 

onBlockAdded:

public void onBlockAdded(World world, int i, int j, int k) {
super.onBlockAdded(world, i, j, k);
TileEntityChameleon tile = (TileEntityChameleon) world.getTileEntity(i, j, k);
tile.updateMaster();
}

 

updateMaster:

public void updateMaster() {
int i = xCoord, j = yCoord, k = zCoord;
if (side == ForgeDirection.DOWN)
	j--;
if (side == ForgeDirection.UP)
	j++;
if (side == ForgeDirection.NORTH)
	k--;
if (side == ForgeDirection.EAST)
	i++;
if (side == ForgeDirection.SOUTH)
	k++;
if (side == ForgeDirection.WEST)
	i--;

master = worldObj.getBlock(i, j, k);
int meta = worldObj.getBlockMetadata(i, j, k);
worldObj.setBlockMetadataWithNotify(xCoord, yCoord, zCoord, meta, 3);
markDirty();
worldObj.markBlockForUpdate(xCoord, yCoord, zCoord);
worldObj.notifyBlocksOfNeighborChange(xCoord, yCoord, zCoord, master, side.ordinal());
}

if (side == ForgeDirection.WEST)
	i--;

master = worldObj.getBlock(i, j, k);
int meta = worldObj.getBlockMetadata(i, j, k);
worldObj.setBlockMetadataWithNotify(xCoord, yCoord, zCoord, meta, 3);
markDirty();
worldObj.markBlockForUpdate(xCoord, yCoord, zCoord);
worldObj.notifyBlocksOfNeighborChange(xCoord, yCoord, zCoord, master, side.ordinal());

How are "side" and "master" defined ? Don't you need a check before changing the "master" field ?

The last two lines are unnecessary. You are already doing it with World#setBlockMetadataWithNotify(..., 3).

 

Do you override markDirty() with something ?

 

  • Author

How are "side" and "master" defined ? Don't you need a check before changing the "master" field ?

The last two lines are unnecessary. You are already doing it with World#setBlockMetadataWithNotify(..., 3).

 

Do you override markDirty() with something ?

 

side and master:

public Block master = Blocks.air;
ForgeDirection side = ForgeDirection.DOWN;

 

And the lines would be unnecessary, if I wouldn't set metadata to 0 sometimes (block was air before -> meta=0 -> no blockUpdate called because no metadata changed)

I tried without.

And no, I didn't override markDirty()

  • Author

It seems to be fixed with this code:

Block oldMaster = master;
int oldMeta = worldObj.getBlockMetadata(xCoord, yCoord, zCoord);

master = worldObj.getBlock(i, j, k);
if (master == Chameleon.chameleon) {
TileEntityChameleon tile2 = (TileEntityChameleon) worldObj.getTileEntity(i, j, k);
master = tile2.master;
}

int meta = worldObj.getBlockMetadata(i, j, k);
if (meta != oldMeta) {
worldObj.setBlockMetadataWithNotify(xCoord, yCoord, zCoord, meta, 3);
} else if (master != oldMaster) {
worldObj.markBlockForUpdate(xCoord, yCoord, zCoord);
// markDirty();
worldObj.notifyBlocksOfNeighborChange(xCoord, yCoord, zCoord, master, side.ordinal());
}

 

But still, can someone explain me what I did do so wrong that it would cause a NoClassDefFoundError???

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