code: public synchronized void write(int blockOffset, byte[] buffer, int offset, int length)
  			throws IOException {
  		provider.write(blockNumber, blockOffset, buffer, offset, length);
  	}
docs: Writes a number of bytes to this block.
  
  @param blockOffset Offset within the block to commence writing at.
  @param buffer Buffer storing the data to be written.
  @param offset Offset within the buffer from where to read.
  @param length Number of bytes to be written.