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[主观题]
下面ButtonFrame类创建了一个容器,包含有3个按键。 import javax.swing.*; public class
ButtonFrame. extends JFrame. { JButton Button1= new JButton("Button1"); JButton Button2= new JButton("Button2"); JButton Button3= new JButton("Button3"); public ButtonFrame() { super("ButtonFrame"); setSize(100,150); setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); JPane1 pane = new JPanel(); pane.add(Buttonl); pane.add(Button2); pane.add(Button3); 【 】; } public static void main(String args[]) { ButtonFrame. bf= new ButtonFrame(); bf.show(); } } 请在程序代码中的画线处添上正确的语句,使程序完整。
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