Question

我借用了stackoverflow上的设计，将控制台输出重定向到GUI。它工作正常，直到我开始从我的程序中的文本文件中读取。现在，当我使用GUI运行程序时，不会显示任何输出，GUI会冻结，然后最终自行关闭。这是我的GUI代码的精简版：

public class GreenhouseControlsGUI {
    public static class MyGui extends JFrame implements ActionListener {

      // Start button 
      JButton Start = new JButton("Start");

      /..................................../

      /**
       * The constructor.
       */ 
     public MyGui(){     
        super("Greenhouse Controls");

            /............................../

        bottomPanel.setLayout(new FlowLayout());
        bottomPanel.add(Start);

            /............................../

        getContentPane().add(holdAll, BorderLayout.CENTER);

        Start.addActionListener(this);

            /............................../

        setDefaultCloseOperation(DISPOSE_ON_CLOSE);
     }

    public void actionPerformed(ActionEvent e){

        if (e.getSource() == Start)
            GreenhouseControls.startMeUp(); // Start program...

            /............................../
        }

    public static void main(String[] args){

        MyGui myApplication = new MyGui();

        // redirect output to GUI
        myApplication.redirectSystemStreams();

        // Specify where will it appear on the screen:
        myApplication.setLocation(10, 10);
        myApplication.setSize(500, 300);

        // Show it!
        myApplication.setVisible(true);
      } 

      private void updateTextArea(final String text) {
            SwingUtilities.invokeLater(new Runnable() {
              public void run() {
                myText.append(text);
              }
            });
          }

      private void redirectSystemStreams() {

          OutputStream out = new OutputStream() {

              @Override
              public void write(int b) throws IOException {
                updateTextArea(String.valueOf((char) b));
              }

              @Override
              public void write(byte[] b, int off, int len) throws IOException {
                updateTextArea(new String(b, off, len));
              }

              @Override
              public void write(byte[] b) throws IOException {
                write(b, 0, b.length);
              }
            };

            System.setOut(new PrintStream(out, true));
            System.setErr(new PrintStream(out, true));
          }
    }
}

我非常确定我的问题始于从＆＃39;文件名＆＃39;以下代码中的路径，因为当我评论＆＃39;文件名时，我没有遇到此问题。变量声明。我认为将控制台输出重定向到我的GUI的方法只是重定向输出....当我从文件中读取时为什么会搞砸一切？我是编程新手，我可能忽略了一些明显的东西，但我无法弄清楚。

这是在GUI类中调用的静态startMeUp（）方法：

public static void startMeUp() {
        try {
            String option   = "-f";                    // (-f) to start program or (-d) to restore program
            filename = "src/greenhouse/examples3.txt"; // read file from here
            dumpFile = "dump.out";                     // restore program from here

            // if option is invalid invoke corresponding print statement
            if ( !(option.equals("-f")) && !(option.equals("-d")) ) {
               System.out.println("Invalid option");
                printUsage();
            }

            GreenhouseControls gc = new GreenhouseControls(); // Create GreenhouseControls object 
            Restart restart = new Restart(0,filename, gc);    // Create Restart object
            Restore restore = new Restore(0,dumpFile);        // Create Restore object

            // if the option value is -f ... 
            if (option.equals("-f"))  {
                gc.addEvent(restart);      // add new Restart object to addEvent() 
            }
            gc.run();                                   

            // if the option value is -d ... 
            if (option.equals("-d"))  {
                gc.addEvent(restore);     // add new Restore object to addEvent()
            }
            gc.run();

            }catch (ArrayIndexOutOfBoundsException e) {
            System.out.println("Invalid number of parameters");
            printUsage();
        }
    }

Answer 1

您需要在新线程中调用startMeUp，因为您的控制台程序阻止了事件派发线程。像这样：

new Thread () {
  @Override public void run () {
    GreenhouseControls.startMeUp();
  }
}.start();

而不仅仅是

GreenhouseControls.startMeUp();

将控制台输出重定向到GUI

1 个答案: