/**
 * java 之流式布局
 * @author gao
 */
package com.gao;

import java.awt.FlowLayout;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.border.EmptyBorder;

@SuppressWarnings("serial")
public class FlowLayoutDemo extends JFrame {
	private JPanel contentPane;
    private JButton button1;
    private JButton button2;
    private JButton button3;
    private JButton button4;
    private JButton button5;
    private JButton button6;
    private JButton button7;
    private JButton button8;
    private JButton button9;
	public FlowLayoutDemo() {
        this.contentPane=new JPanel();//创建内容面板
        this.contentPane.setBorder(new EmptyBorder(5,5,5,5));//设置面板的边框
        this.setContentPane(contentPane);//应用内容面板
        this.contentPane.setLayout(new FlowLayout(FlowLayout.CENTER,5,5));//设置内容面板的布局管理器为流式布局
        
        this.button1=new JButton("按钮1");//创建按钮
        this.button2=new JButton("按钮2");
        this.button3=new JButton("按钮3");
        this.button4=new JButton("按钮4");
        this.button5=new JButton("按钮5");
        this.button6=new JButton("按钮6");
        this.button7=new JButton("按钮7");
        this.button8=new JButton("按钮8");
        this.button9=new JButton("按钮9");
        this.contentPane.add(button1);//在面板上增加按钮
        this.contentPane.add(button2);
        this.contentPane.add(button3);
        this.contentPane.add(button4);
        this.contentPane.add(button5);
        this.contentPane.add(button6);
        this.contentPane.add(button7);
        this.contentPane.add(button8);
        this.contentPane.add(button9);
		this.setTitle("流式布局");//设置窗体的标题
		this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);//设置窗体退出时操作
		this.setBounds(100, 100, 300, 150);//设置窗体位置和大小
		this.setVisible(true);//设置窗体可见

	}

	public static void main(String[] args) {
		FlowLayoutDemo example = new FlowLayoutDemo();
	}
}

Demo 运行结果：

当窗体拉伸时候，按钮位置会改变

Java Swing 之流式布局管理器