use*_*571 0 java static joptionpane
JOptionPane jop = new JOptionPane( );
jop.showMessageDialog(“This is never done”);
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我被告知这样做的味道很差.我的意思是它有效,但显然"pro"不会这样做,因为showMessageDialog是静态的.有没有更好的方法来写这个?
甲static方法可以在不向实例的引用被调用:
JOptionPane.showMessageDialog("This is never done");
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实际上,这些行:
JOptionPane jop = new JOptionPane();
jop.showMessageDialog("This is never done");
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将在编译时转换为:
JOptionPane jop = new JOptionPane();
JOptionPane.showMessageDialog("This is never done");
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