code: @Override
      public void addWriteInterest(){
          if(transportOut.peekOut==this)
              transportOut.peekOutInterested = true;
          if(engine.isOutboundDone())
              transportOut.wakeupWriter();
          else{
              if(selfInterests==0)
                  peerOut.addWriteInterest();
              else{
                  if((selfInterests&OP_READ)!=0)
                      peerIn.addReadInterest();
                  if((selfInterests&OP_WRITE)!=0)
                      peerOut.addWriteInterest();
              }
          }
      }
docs: /*-------------------------------------------------[ App Write ]---------------------------------------------------