code: public synchronized void addBuffer(byte[] buf, int off, int len) {
  		if (copyBuffers) {
  			byte[] b = new byte[len];
  			System.arraycopy(buf, off, b, 0, len);
  			buf = b;
  			off = 0;
  		}
  		buffers.add(new Triple<>(buf, Integer.valueOf(off), Integer.valueOf(len)));
  		totalSize += len;
  	}
docs: Append the given buffer.