我正在使用一些多线程应用程序进行Java swing。这种情况是这样的,我需要一个接一个地执行一个线程,即我的一个输出与第二个线程有关。我做了以下。

// Class one
public class Samp implements Runnable{
    public Samp(String name) {
       this.setName = name;
    }
    public void run (){
      // Here I have a file extraction method called
      extract(this.getName);
    }

   // Extract Method
   public Boolean extract(String filename){
     // Some extraction Operation.
     // I want to update the jTextField with the current filename under     extraction.
   }
}


// GUI类

public class Welcome extends javax.swing.JFrame {
   SwingWorker<Boolean, Void>worker =  new SwingWorker<Boolean, Void>() {
        @Override
        protected Boolean doInBackground() throws Exception {
            Thread t1 = new Thread(new ZipUtility(fileName));
            t1.start();
            return true;
        }

        // Can safely update the GUI from this method.
        @Override
        protected void done() {
            // Here when this worker is done I wanted to Run worker 2
        }
    };

    SwingWorker<Boolean, Void>worker2 = .........

   // Again when worker2 is done I wanted to run worker 3 and so on.
 }


我的问题是:

1)如何以完美的顺序运行所有工人。也就是说,当worker1完成后,启动worker 2,当worker2完成后,启动worker 3,依此类推。

2)如何使用Samp类中的值更新我的Welcome类中的文本字段。

提前致谢。

最佳答案

1)如何以完美的顺序运行所有工人。也就是说,当worker1完成后,启动worker 2,当worker2完成后,启动worker 3,依此类推。


请记住一个小技巧,您可以将SwingWorker放入ExecutorService

因此,使用类似...

public static class Worker extends SwingWorker {

    private int sequence;

    public Worker(int sequence) {
        this.sequence = sequence;
    }

    @Override
    protected Object doInBackground() throws Exception {
        System.out.println(sequence + "...");
        Thread.sleep(500);
        return null;
    }

}


作为测试,您可以使用...

ExecutorService es = Executors.newFixedThreadPool(1);
for (int index = 0; index < 10; index++) {
    es.submit(new Worker(index));
}
es.shutdown();


(您不需要调用shutdown,否则我的测试永远不允许JVM终止;)

这将按照提交的顺序运行这些工作程序。

现在,如果要将值从一个SwingWorker馈给另一个,可以执行以下操作:

public abstract class ChainedWorker<T, V> extends SwingWorker<T, V> {

    private ChainedWorker<T, ?> next;
    private T previousValue;

    public ChainedWorker(ChainedWorker<T, ?> next) {
        this.next = next;
    }

    public void setPreviousValue(T previousValue) {
        this.previousValue = previousValue;
    }

    @Override
    protected void done() {
        try {
            T previous = get();
            if (next != null) {
                next.setPreviousValue(previous);
                next.execute();
            }
        } catch (InterruptedException | ExecutionException ex) {
            ex.printStackTrace();
        }
    }

}


这只是一个SwingWorker,它允许您在链中提供链接(下一个要调用的工作程序),该链接传递此SwingWorker生成的值...或某些类似的值

现在,如果您真的很疯,想扮演自己的角色,那么也许...

public class ChainedWorkerBuilder {

    private List<SwingWorker> workers;
    private SwingWorker current;

    public ChainedWorkerBuilder() {
        workers = new ArrayList<>(25);
    }

    public ChainedWorkerBuilder add(SwingWorker worker) {
        workers.add(worker);
        return this;
    }

    public void execute() {
        if (!workers.isEmpty()) {
            SwingWorker worker = workers.remove(0);
            worker.addPropertyChangeListener(new PropertyChangeListener() {
                @Override
                public void propertyChange(PropertyChangeEvent evt) {
                    if ("state".equals(evt.getPropertyName())) {
                        SwingWorker source = (SwingWorker)evt.getSource();
                        switch (source.getState()) {
                            case DONE:
                                source.removePropertyChangeListener(this);
                                execute();
                                break;
                        }
                    }
                }
            });
        }
    }

}



  2)如何使用Samp类中的值更新我的Welcome类中的文本字段。


我不认为我会直接遵循您的代码,但是,如果您做了类似的事情……

SwingWorker<Boolean, Void>worker =  new SwingWorker<Boolean, String>() {

    protected Boolean doInBackground() throws Exception {
        publish(fileName);
        ZipUtility zu = new ZipUtility(fileName));
        return zu.extract(fileName);
    }


然后,在SwingWorker s process方法中,您将能够安全地更新UI ...

    @Override
    protected void process(List<String> chunks) {
        // Grab the last element...
        textfield.setText(chunks.get(chunks.size() - 1));
    }
}

关于java - Java Swingworker接连更新GUI,我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/31580805/

10-12 00:22