面板 JPanel，滚动面板 JScrollPane，文本域JTextArea

容器中可以有多个JPanel面板，一个JPanel面板中可以有多个控件。

滚动面板 JScrollPane中只能有一个控件。

     

public class Demo extends JFrame {
    public Demo() {
        setBounds(100, 100, 600, 200);
        setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
        Container c = getContentPane();
        c.setLayout(new GridLayout(1, 2, 10, 10));
        //创建2个面板
        JPanel p1 = new JPanel();
        p1.setLayout(new GridLayout(1, 3));
        JPanel p2 = new JPanel(new BorderLayout());
        p2.setBackground(Color.BLUE);
        //设置面板边框，标题
        p1.setBorder(BorderFactory.createTitledBorder("面板1"));
        p2.setBorder(BorderFactory.createTitledBorder("面板2"));
        p1.add(new JButton("b1"));
        p1.add(new JButton("b1"));
        p1.add(new JButton("b1"));
        p1.add(new JButton("b1"));
        p2.add(new JButton("b2"), BorderLayout.EAST);
        p2.add(new JButton("b2"), BorderLayout.WEST);
        p2.add(new JButton("b2"), BorderLayout.SOUTH);
        p2.add(new JButton("b2"), BorderLayout.NORTH);
        p2.add(new JButton("b2"));
        c.add(p1);
        c.add(p2);
        setVisible(true);
    }

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

public class Demo extends JFrame {
    public Demo() {
        setBounds(100, 100, 200, 100);
        setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
        Container c = getContentPane();
        JTextArea area=new JTextArea();//文本域
        JScrollPane sp=new JScrollPane(area);//将文本域添加到滚动面板中
        c.add(sp);
        setVisible(true);
    }

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