按钮JButton，单选按钮JRadioButton，复选框JCheckBox

1、按钮JButton  

public class Demo extends JFrame {
    public Demo() {
        setBounds(100, 100, 400, 200);
        setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
        Container c = getContentPane();
        c.setLayout(new GridLayout(2, 3, 10, 10));
        JButton btn[] = new JButton[6];//定义6个按钮数组
        for (int i = 0; i < btn.length; i++) {
            btn[i] = new JButton();//创建按钮
            c.add(btn[i]);
        }
        btn[0].setText("不可用");
        btn[0].setEnabled(false);
        btn[1].setText("背景色");
        btn[1].setBackground(Color.GREEN);
        btn[2].setText("无边框");
        btn[2].setBorderPainted(false);
        btn[3].setText("有边框");
        btn[3].setBorder(BorderFactory.createLineBorder(Color.RED));
        setVisible(true);
        Icon icon=new ImageIcon("src/logo.png");
        btn[4].setIcon(icon);//给按钮设置图片
        btn[4].setToolTipText("图片按钮");//鼠标悬停提示
        btn[5].setText("弹出提示框");
        btn[5].addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                JOptionPane.showMessageDialog(Demo.this,"这是消息提示框");
            }
        });
    }

    public static void main(String[] args) {
        new Demo();
    }
}

 2、单选按钮JRadioButton

public class Demo extends JFrame {
    public Demo() {
        setBounds(100, 100, 200, 100);
        setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
        Container c = getContentPane();
        c.setLayout(new FlowLayout());
        JRadioButton rb1 = new JRadioButton("男");
        JRadioButton rb2 = new JRadioButton("女");
        c.add(rb1);
        c.add(rb2);
        ButtonGroup group=new ButtonGroup();//按钮组，使按钮单选，而不被同时选中
        group.add(rb1);
        group.add(rb2);
        rb1.setSelected(true);//默认选中
        setVisible(true);
    }

    public static void main(String[] args) {
        new Demo();
    }
}

 3、复选框JCheckBox

public class Demo extends JFrame {
    public Demo() {
        setBounds(100, 100, 200, 100);
        setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
        Container c = getContentPane();
        c.setLayout(new FlowLayout());
        JCheckBox cb1=new JCheckBox("桔子");
        JCheckBox cb2=new JCheckBox("苹果");
        JCheckBox cb3=new JCheckBox("香蕉");
        cb1.setSelected(true);//默认选中
        c.add(cb1);c.add(cb2);c.add(cb3);
        setVisible(true);
    }

    public static void main(String[] args) {
        new Demo();
    }
}