code: private void fillPacket() throws IOException
      {
          if (_closed)
              return;
  
          if (_gotFirst||_in.available()==0)
              _getBodyChunk.write(_out);
          _gotFirst=true;
  
          // read packet
          if (!_packet.read(_in))
              throw new IOException("EOF");
  
          if (_packet.unconsumedData()<=0)
              _closed=true;
          else if (_packet.getInt()>_packet.getBufferSize())
              throw new IOException("AJP Protocol error");
      }
docs: /* ------------------------------------------------------------