Regenerate chunk

Chunk oldChunk = world.getChunkFromBlockCoords(position);
if (world instanceof WorldServer)
{
    WorldServer worldServer = (WorldServer) world;
    ChunkProviderServer chunkProviderServer = worldServer.theChunkProviderServer;
    IChunkProvider chunkProviderGenerate = chunkProviderServer.serverChunkGenerator;

    Chunk newChunk = chunkProviderGenerate.provideChunk(oldChunk.xPosition, oldChunk.zPosition);
    BlockPos chunkPos = new BlockPos(oldChunk.xPosition * 16, 0, oldChunk.zPosition * 16);
    for (int x = 0; x < 16; x++)
    {
        for (int z = 0; z < 16; z++)
        {
            for (int y = 0; y < world.getHeight(); y++)
            {
                BlockPos posInChunk = new BlockPos(x, y, z);
                BlockPos pos = chunkPos.add(posInChunk);
                IBlockState state = newChunk.getBlockState(posInChunk);

                worldServer.setBlockState(pos, state, 2);

                TileEntity tileEntity = newChunk.getTileEntity(posInChunk, Chunk.EnumCreateEntityType.IMMEDIATE);
                if (tileEntity != null)
                {
                    worldServer.setTileEntity(pos, tileEntity);
                }
            }
        }
    }
    ObfuscationReflectionHelper.setPrivateValue(Chunk.class, oldChunk, false, "field_76646_k", "isTerrainPopulated");
    chunkProviderGenerate.populate(chunkProviderGenerate, oldChunk.xPosition, oldChunk.zPosition);
}