Connection checking example

BlockCable

@Override
public void onNeighborBlockChange(World world, int x, int y, int z, int newId) {
  for (ForgeDirection side : ForgeDirection.VALID_DIRECTIONS) {
    if (world.getBlockTileEntity(x + side.offsetX, y + side.offsetY, z + side.offsetZ) instanceof TileCable) {
      TileCable tile = (TileCable) world.getBlockTileEntity(x + side.offsetX, y + side.offsetY, z + side.offsetZ);
      tile.checkConnections();
    }
  }
}