swing程序设计

package shiyan;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.*;

public class swing implements ActionListener {
 JFrame a;
 JPanel b;
 JButton c1,c2;
 JTextField d1,d2,d3;
 JLabel e1,e2,e3,e4;
 GridLayout g1;
 
 public  swing(){
  a=new JFrame("计算器");
  b=new JPanel();
  c1=new JButton("求和");
  c1.addActionListener(this);
  c2=new JButton("清除");
  c2.addActionListener(this);
  d1=new JTextField();
  d2=new JTextField();
  d3=new JTextField();
  e1=new JLabel("加数1");
  e2=new JLabel("加数2");
  e3=new JLabel();
  e4=new JLabel();
  g1=new GridLayout(3,3);
  b.setLayout(g1);
  a.setSize(400,300);
  a.add(b);
  b.add(e1);
  b.add(d1);
  b.add(e3);
  b.add(e2);
  b.add(d2);
  b.add(e4);
  b.add(c1);
  b.add(d3);
  b.add(c2);
  a.setVisible(true);
 }
    
 public static void main(String[] args){
  new  swing();
 }

 public void actionPerformed(ActionEvent e) {
     if(e.getActionCommand().equals(c1.getText())){
         int a,b,c;
         a=Integer.parseInt(d1.getText());
         b=Integer.parseInt(d2.getText());
         c=a+b;
         d3.setText(c+"");
              }
     if(e.getActionCommand().equals(c2.getText())){
         d1.setText(null);
         d2.setText(null);
         d3.setText(null);
     }
 }
}

　　运行截图：