Cannot reduce the visibility of the inherited method from 编译错误

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编译如下代码时，

<pre name="code" class="java">JDesktopPane DESKTOP_PANE = new JDesktopPane() {protected void paintComponent(Graphics g) {g.drawImage(image, 0, 0, getWidth(), getHeight(), null);//g.drawImage(image, 0, 0, 500, 400, null);}};

一切正常。编译如下代码时，

JDesktopPane DESKTOP_PANE = new JDesktopPane() {//protected void paintComponent(Graphics g) {<pre name="code" class="java">                                 protected  void paint(Graphics g) {g.drawImage(image, 0, 0, getWidth(), getHeight(), null);//g.drawImage(image, 0, 0, 500, 400, null);}};

发生错误，提示如下信息：

Multiple markers at this line
- overrides javax.swing.JLayeredPane.paint
- Cannot reduce the visibility of the inherited method from

经查 JDesktopPane有paintComponet 和paint 方法。具体而言：

1. paintComponet继承自javax.swing.JComponent。原型： protected void paintComponent(Graphics g)

2. paint 继承自 javax.swing.JLayeredPane。原型： public void paint(Graphics g)

发生错误的原因是复写父类的方法,父类是 public 子类变为了protected,违反了两同两小一大的一大原则。故错误。修改为public 正确。

http://stackoverflow.com/questions/9035052/cannot-reduce-visibility-of-method-inherited-method-from-parent

http://stackoverflow.com/questions/6851612/java-access-modifiers-and-overriding-methods

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