在这种情况下，当我想停止 SwingWorker 时，我做错了什么？

Question

public class Worker extends SwingWorker<Integer, String> {
private JLabel screen;

    public Worker(JLabel screen) {
        this.screen = screen;
    }

    @Override
    protected Integer doInBackground() throws Exception {
        for (; ; ) {
            publish(String.valueOf(Calendar.getInstance().getTimeInMillis()));
        }
    }

    @Override
    protected void process(List<String> chunks) {
        screen.setText(chunks.get(0));
    }
}

在表格中：

    public class Form extends JPanel{
    private JButton startButton;
    private JPanel rootPanel;
    private JButton stopButton;
    private JLabel screen;
    private Worker worker;

    public Form() {
        startButton.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                worker = new Worker(screen);
                worker.execute();
            }
        });
        stopButton.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                worker.cancel(true);
                System.out.println(worker.isDone());
                System.out.println(worker.isCancelled());
            }
        });
    }

    private void createUIComponents() {
        rootPanel = this;
    }
}

我尝试用 Tread 编写相同的代码，但它也不起作用。单击停止按钮后控制台输出：

true

true

所以，worker 已经完成了，但是程序仍然继续显示毫秒。什么是post-死亡生命？如果使用 Thread 同样的事情：方法 isAlive() return "false".

Answer 1

根据您的代码，您似乎需要一个带有循环的工作程序来保持运行，直到主线程告诉它停止运行，这是通过 worker.cancel(true); 完成的.问题是你正在取消它，但没有做任何事情来通知循环本身停止迭代。要解决此问题，您应该更改

for (; ; ) {
    publish(String.valueOf(Calendar.getInstance().getTimeInMillis()));
}

到

while(!isCancelled()){
    publish(String.valueOf(Calendar.getInstance().getTimeInMillis()));
}

请注意 java 文档中 'isCancelled' 的措辞：

isCancelled()

Returns true if this task was canceled before it completed normally. Since the loop never closes on its' own, it will never complete normally.

在这种情况下，当我想停止 SwingWorker 时，我做错了什么？

What did I wrong when I want to stop SwingWorker in this case?

java

swing

multithreading

swingworker