控制台:Exception in thread "main" java.lang.StackOverflowError
at sun.awt.Win32GraphicsConfig.getBounds(Native Method)
at sun.awt.Win32GraphicsConfig.getBounds(Win32GraphicsConfig.java:240)
at java.awt.Window.init(Window.java:368)
at java.awt.Window.<init>(Window.java:407)
at java.awt.Frame.<init>(Frame.java:402)
at java.awt.Frame.<init>(Frame.java:367)
at javax.swing.JFrame.<init>(JFrame.java:163)
at com.班级系统.JPanel.<init>(JPanel.java:18)
at com.班级系统.JPanel.<init>(JPanel.java:21)
at com.班级系统.JPanel.<init>(JPanel.java:21)
at com.班级系统.JPanel.<init>(JPanel.java:21)
at com.班级系统.JPanel.<init>(JPanel.java:21)
at com.班级系统.JPanel.<init>(JPanel.java:21)
at com.班级系统.JPanel.<init>(JPanel.java:21)
at com.班级系统.JPanel.<init>(JPanel.java:21)
at com.班级系统.JPanel.<init>(JPanel.java:21)
at com.班级系统.JPanel.<init>(JPanel.java:21)
at com.班级系统.JPanel.<init>(JPanel.java:21)
at com.班级系统.JPanel.<init>(JPanel.java:21)
at com.班级系统.JPanel.<init>(JPanel.java:21)
at com.班级系统.JPanel.<init>(JPanel.java:21)
at com.班级系统.JPanel.<init>(JPanel.java:21)
at com.班级系统.JPanel.<init>(JPanel.java:21)
at com.班级系统.JPanel.<init>(JPanel.java:21)
at com.班级系统.JPanel.<init>(JPanel.java:21)
at com.班级系统.JPanel.<init>(JPanel.java:21)
at com.班级系统.JPanel.<init>(JPanel.java:21)
at com.班级系统.JPanel.<init>(JPanel.java:21)
at com.班级系统.JPanel.<init>(JPanel.java:21)
at com.班级系统.JPanel.<init>(JPanel.java:21)
at com.班级系统.JPanel.<init>(JPanel.java:21)
at com.班级系统.JPanel.<init>(JPanel.java:21)
at com.班级系统.JPanel.<init>(JPanel.java:21)
at com.班级系统.JPanel.<init>(JPanel.java:21)
at com.班级系统.JPanel.<init>(JPanel.java:21)
at com.班级系统.JPanel.<init>(JPanel.java:21)
at com.班级系统.JPanel.<init>(JPanel.java:21)
at com.班级系统.JPanel.<init>(JPanel.java:21)
at com.班级系统.JPanel.<init>(JPanel.java:21)
at com.班级系统.JPanel.<init>(JPanel.java:21)
at com.班级系统.JPanel.<init>(JPanel.java:21)
at com.班级系统.JPanel.<init>(JPanel.java:21)
at com.班级系统.JPanel.<init>(JPanel.java:21)
/**
* 功能:文本框,密码框,标签
*/
package com.班级系统;
import java.awt.*;
import javax.swing.*;
public class demo8_6 extends JFrame{ //定义组建
JLabel jlb1,jlb2;
JPanel jp1,jp2,jp3;
JPasswordField jpf1;
JTextField jtf1;
JButton jb1,jb2;
public static void main(String[] args) {
// TODO 自动生成的方法存根
demo8_6 demo=new demo8_6();
} public demo8_6()
{
//创建组件
jlb1=new JLabel("用户名");
jlb2=new JLabel("密码");
jpf1=new JPasswordField(10);
jtf1=new JTextField(10);
jp1=new JPanel();
jp2=new JPanel();
jb1=new JButton("确认");
jb2=new JButton("取消");
//设置布局
this.setLayout(new GridLayout(3,1));
//添加组件
jp1.add(jlb1);
jp1.add(jtf1);
jp2.add(jlb2);
jp2.add(jpf1);
jp3.add(jb1);
jp3.add(jb2);
this.add(jp1);
this.add(jp2);
this.add(jp3);
//设置窗体
this.setSize(200, 150);
this.setVisible(true);
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
}
jp2 = new JPanel();
jp3 = new JPanel();加一句这个就行了,运行可以通过