[求助]出现"找不到符号"错误

随便练习练习

代码如下:
import java.awt.*;

class aaa extends Frame{
TextField txt=new TextField(20);
Label lbl1=new Label("名称:");
Label lbl2=new Label("备注");
TextArea area=new TextArea();
Button btn0=new Button("确定");
GridBagLayout gb;
GridBagConstraints gbc;

public aaa(String a){
super(a);
gb=new GridBagLayout();
setLayout(gb);

gbc=new GridBagConstraints();

gbc.fill=GridBagConstraints.BOTH;
addC(lbl1,0,0,5,1);
gbc.fill=GridBagConstraints.HORIZONTAL;
addC(lbl2,0,5,5,1);
gbc.fill=GridBagConstraints.HORIZONTAL;
addC(area,5,0,10,10);

}
public void addC(Component c,int row,int col,int nrow,int ncol){
gbc.gridx=col;
gbc.gridy=row;

gbc.gridwidth=ncol;
gbc.gridheight=nrow;

gb.setConstraints(c,gbc);
add(c);
}
class bbb extends Panel{

}
class ccc{
public static void main(String args[]){
aaa n=new aaa("测试");
bbb m=new bbb();

n.add(m);
m.setName("aaa");
n.setSize(500,300);
n.show();

n.addWindowListener(new WindowAdapter(){
public void windowClosing(WindowEvent e)
{
System.exit(0);
}
});
}
}

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添加import java.awt.event.*;
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谢谢
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class ccc{
public static void main(String args[]){... ...
在程序中是不是多了 static 因为在内部类中不能有静态声明.

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楼上说的有道理，普通内部类里面是不能有静态声明的，但是静态内部类可以有静态声明

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