code: @Override
      public boolean isReady() {
  
          if(this.isOutputStreamNBClosed()){
              if (TraceComponent.isAnyTracingEnabled() && tc.isDebugEnabled()){  
                  Tr.debug(tc, "output stream closed, ready->" + false);
              }
              return false;
          }
          return this.isWriteReadyWork(true);
      }
docs: /* (non-Javadoc)
  @see javax.servlet.ServletOutputStream#isReady()