for循环中的JProgressBar

Question

抱歉，这是我正在尝试使用JProgressBar的任务的地方：

class Task extends SwingWorker<Void, Void> {       
    @Override
    public Void doInBackground() {
        for (int i = 0; i <= 100; i++) {
        doTheWork();//where work happens
        System.out.println(i);
        jProgressBar1.setValue(i);
    }
        return null;
    }
    @Override
    public void done() {
        Toolkit.getDefaultToolkit().beep();
        jButton1.setEnabled(true);
        setCursor(null); //turn off the wait cursor
    }
}



private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {                                         
    jButton1.setEnabled(false);
    setCursor(java.awt.Cursor.getPredefinedCursor(java.awt.Cursor.WAIT_CURSOR));
    //Instances of javax.swing.SwingWorker are not reusuable, so
    //we create new instances as needed.
    task = new Task();
    task.addPropertyChangeListener(this);
    task.execute();


}               

问题是task.addPropertyChangeListener（this）;抛出错误，因为我的主类扩展了JFrame并且无法实现ActionListener，PropertyChangeListener，因为按照oracle示例，它不是抽象的。我不明白为什么。

错误是没有为ActionListner重写方法，必须添加：

@Override
public void actionPerformed(ActionEvent e) {
    throw new UnsupportedOperationException("Not supported yet."); //To change body of generated methods, choose Tools | Templates.
}