code: private void writeBufferToFile() throws IOException {
          if (_bufferOffset > 0) {
              List<ByteBuffer> payload = new ArrayList<ByteBuffer>(1);
              payload.add(ByteBuffer.wrap(_buffer, 0, _bufferOffset));
              NfsWriteResponse response = _nfsFile.write(_currentOffset, payload, _syncType);
              int bytesWritten = response.getCount();
              _currentOffset += bytesWritten;
              _bufferOffset -= bytesWritten;
              if (0 != _bufferOffset) { // Everything was not written.
                  // _bufferOffset should be the number of unwritten bytes.
                  // Copy the unwritten bytes to the beginning of the buffer.
                  System.arraycopy(_buffer, bytesWritten, _buffer, 0, _bufferOffset);
              }
          }
      }
docs: Write the buffer contents to the file and reset the buffer afterwards.
  
  @throws IOException