import java.awt.Container;import java.awt.GridLayout;import java.awt.event.ItemEvent;import java.awt.event.ItemListener;import java.awt.event.WindowAdapter;import java.awt.event.WindowEvent;import javax.swing.BorderFactory;import javax.swing.ButtonGroup;import javax.swing.JCheckBox;import javax.swing.JFrame;import javax.swing.JPanel;import javax.swing.JRadioButton;//=================================================// File Name       :	JCheckBox_demo//------------------------------------------------------------------------------// Author          :	Common// 类名：JCheckBox// 属性：// 方法：class MyCheckBox implements ItemListener{	private JFrame frame = new JFrame("窗体");	private Container cont = frame.getContentPane();	private JCheckBox jrb1  = new JCheckBox("单选1");	private JCheckBox jrb2  = new JCheckBox("单选2"); 	private JCheckBox jrb3  = new JCheckBox("单选3"); 	private JPanel pan = new JPanel();	public MyCheckBox(){		//定义一个面板的边框显示条		pan.setBorder(BorderFactory.createTitledBorder("请选择按钮"));		pan.setLayout(new GridLayout(1,3));		pan.add(this.jrb1);		pan.add(this.jrb2);		pan.add(this.jrb3);				jrb1.addItemListener(this); 			//加入事件监听		jrb2.addItemListener(this); 			//加入事件监听		jrb3.addItemListener(this); 			//加入事件监听				cont.add(pan);		this.frame.setSize(330,80);		this.frame.setVisible(true);		this.frame.addWindowListener(new WindowAdapter(){			public void windowClosing(WindowEvent e) {			//窗口关闭时触发，按下关闭按钮			// TODO 自动生成的方法存根			System.out.println("windowClosing-->窗口关闭");			System.exit(1);			}		});	}	@Override	public void itemStateChanged(ItemEvent e) {		// TODO 自动生成的方法存根		if(jrb1.isSelected()){			System.out.println("jrb1");		}		if(jrb2.isSelected()){			System.out.println("jrb2");		}		if(jrb3.isSelected()){			System.out.println("jrb3");		}	}}//主类//Function        : 	JCheckBox_demopublic class JCheckBox_demo {	public static void main(String[] args) {		// TODO 自动生成的方法存根		new MyCheckBox();	}}