java - 我如何调用一个声明 ArrayList 并从另一个方法引用变量的方法？

Question

已关闭。此问题不符合 Stack Overflow guidelines 。目前不接受答案。

---

问题必须表现出对所解决问题的最低限度的理解。告诉我们您尝试过做什么，为什么不起作用，以及它应该如何工作。另请参阅:Stack Overflow question checklist

已关闭 9 年前。

Improve this question

所以我想做destroyProcesses(processes);当我点击我的 stopButton这是 JButton 。我如何让它在我的代码中工作？

这是我的代码:

        private void Processes() throws IOException, InterruptedException {
            // New Thread "processesThread" will start here.
            final Object mon = threadBlock;
            Thread processesThread = new Thread(new Runnable() {
            @Override
                public void run() {
                    synchronized (mon) {
                        try {
                            try {
            Runtime rt = Runtime.getRuntime();
            List<Process> processes = new ArrayList<Process>();
            // "runnableTogether" will be the number that the user inputs in the GUI.
            switch (runnableTogether) {
                case 4:
                    processes.add(rt.exec("C:/Windows/System32/SoundRecorder.exe"));
                case 3:
                    processes.add(rt.exec("C:/Windows/System32/taskmgr.exe"));
                case 2:
                    processes.add(rt.exec("C:/Windows/System32/notepad.exe"));
                case 1:
                    processes.add(rt.exec("C:/Windows/System32/calc.exe"));
                    Thread.sleep(5000);
                    destroyProcesses(processes);
                    break;
                default:
                    System.exit(0);
                    break;
            }
            mon.wait();
                } catch (IOException ex) { 
                }
            } catch (InterruptedException ex) {
                }
            }
        }
    });
            processesThread.start();
            // New Thread "processesThread" will end here.
        }
        private void destroyProcesses(List<Process> processes) {
            if (processes == null) {
                return;
            }
            else {
                for (Process thisProcess : processes) {
                    thisProcess.destroy();
                }
                processes.clear();
            }
        }
    public void actionPerformed(final ActionEvent e) {
        if (e.getSource() == stopButton) {
            try {
                // Destroy processes here.
                System.exit(0);
            }
            catch (Exception ex) {
            }
        }
    }

有什么想法吗？

Answer 1

您需要将进程作为实例变量，如下所示:

public class MyClass {
    private List<Process> processes = new ArrayList<Process>();

    public MyClass() {
        initProcesses();
    }

    private void initProcesses() {
        // init the processes here
    }

    public void actionPerformed(final ActionEvent e) {
        // now here you can use the processes
    }        
}

希望有帮助!