java 小程序未初始化

import java.awt.*;
import java.applet.Applet;
public class qq extends Applet
{
public Button b1,b2,b3,b4;
public Label lab1,lab2,lab3,lab4;
public TextField txt1,txt2;
public CheckboxGroup cbg;
public Checkbox chb1,chb2;
public Choice ch;
public Panel p1,p2,p3,p4,p5;
public void init()
{
p1=new Panel(new GridLayout(1,1,10,10));
lab1=new Label("QQ2009");
lab1.setBackground(Color.blue);
p1.add(lab1);
p2=new Panel(new GridLayout(2,3,10,10));
lab2=new Label("帐号：");
txt1=new TextField(20);
b1=new Button("注册新帐号");
b1.setForeground(Color.blue);
lab3=new Label("密码");
txt2=new TextField(20);
b2=new Button("取回密码");
b2.setForeground(Color.blue);
p2.add(lab2);p2.add(txt1);p2.add(b1);
p2.add(lab3);p2.add(txt2);p2.add(b2);
p3=new Panel(new FlowLayout(FlowLayout.CENTER));
lab4=new Label("状态：");
ch=new Choice();
ch.addItem("我在线上");
ch.addItem("Q我吧");
ch.addItem("离开");
ch.addItem("忙碌");
ch.addItem("请匆打扰");
ch.addItem("隐身");
cbg=new CheckboxGroup();
chb1=new Checkbox("记住密码",cbg,false);
chb2=new Checkbox("自动登录",cbg,false);
p3.add(lab4);p3.add(ch);p3.add(chb1);p3.add(chb2);
p4=new Panel(new GridLayout(1,2,10,10));
b3=new Button("设置");
b3.setBackground(Color.blue);
b4=new Button("自动登录");
b4.setBackground(Color.blue);
p4.add(b3);p4.add(b4);
p5.add(p1);p5.add(p2);p5.add(p3);p5.add(p4);
add(p5);
}
}

这是为什么呀，请给指一下哪里错啦，并给改一下

你贴的代码中没有发现main方法！
这是程序必须要的！

import java.awt.*; import java.applet.Applet; public class qq extends Applet { public Button b1, b2, b3, b4; public Label lab1, lab2, lab3, lab4; public TextField txt1, txt2; public CheckboxGroup cbg; public Checkbox chb1, chb2; public Choice ch; public Panel p1, p2, p3, p4, p5; public void init() { p1 = new Panel(new GridLayout(1, 1, 10, 10)); lab1 = new Label("QQ2009"); lab1.setBackground(Color.blue); p1.add(lab1); p2 = new Panel(new GridLayout(2, 3, 10, 10)); lab2 = new Label("帐号："); txt1 = new TextField(20); b1 = new Button("注册新帐号"); b1.setForeground(Color.blue); lab3 = new Label("密码"); txt2 = new TextField(20); b2 = new Button("取回密码"); b2.setForeground(Color.blue); p2.add(lab2); p2.add(txt1); p2.add(b1); p2.add(lab3); p2.add(txt2); p2.add(b2); p3 = new Panel(new FlowLayout(FlowLayout.CENTER)); lab4 = new Label("状态："); ch = new Choice(); ch.addItem("我在线上"); ch.addItem("Q我吧"); ch.addItem("离开"); ch.addItem("忙碌"); ch.addItem("请匆打扰"); ch.addItem("隐身"); cbg = new CheckboxGroup(); chb1 = new Checkbox("记住密码", cbg, false); chb2 = new Checkbox("自动登录", cbg, false); p3.add(lab4); p3.add(ch); p3.add(chb1); p3.add(chb2); p4 = new Panel(new GridLayout(1, 2, 10, 10)); b3 = new Button("设置"); b3.setBackground(Color.blue); b4 = new Button("自动登录"); b4.setBackground(Color.blue); p4.add(b3); p4.add(b4); p5=new Panel();//主要的问题是没有初始化p5 p5.add(p1); p5.add(p2); p5.add(p3); p5.add(p4); add(p5); } 　//Applet中可有main方法,没有也不影响 public static void main(String args[]) { new qq(); } }

p5未实例化

p5 = new Panel();

没写.所以p5不知道是什么东西.