JFileChooser chooser = new JFileChooser();
// Note: source for ExampleFileFilter can be found in FileChooserDemo,
    // under the demo/jfc directory in the JDK.
    ExampleFileFilter filter = new ExampleFileFilter();
    filter.addExtension("jpg");
    filter.addExtension("gif");
    filter.setDescription("JPG & GIF Images");
    chooser.setFileFilter(filter);
    int returnVal = chooser.showOpenDialog(parent);
    if(returnVal == JFileChooser.APPROVE_OPTION) {
       System.out.println("You chose to open this file: " +
            chooser.getSelectedFile().getName());
    }
这段代码一插如程序中就报错,是怎么原因啊
请大家帮帮忙看看

上边这段代码是jdk 帮助里边的源代码,索引 输入JFileChooser就回出现上面那段代码
一放到程序中就提示错误

问题以解决!