import java.awt.*;
import java.awt.event.*;
public class calculator implements ActionListener
{
  Frame f;
  Panel p1,p2;
  TextField op1,op2,result;
  Button calc,clearb;
  public void show()
  {
    f=new Frame("一个简单的计算器");
    f.setSize(240,180);
    f.setLocation(300,200);
    f.setBackground(Color.lightGray);
    f.setLayout(new FlowLayout());
    result = new TextField(20);
    result.setEditable(false);
    op1=new TextField("0",4);
    op2=new TextField("0",4);
    p1=new Panel();
    p1.add(op1);
    p1.add(new Label("+"));
    p1.add(op2);
    f.add(result);
    f.add(p1);
    calc = new Button("=");
    clearb=new Button("Clear");
    p2=new Panel();
    p2.add(calc);
    p2.add(clearb);
    f.add(p2);
    calc.addActionListener(this);
    clearb.addActionListener(this);
    f.addWindowListener(new WinClose());
    f.setVisible(true);
  }
  public void actionperformed(ActionEvent e)
  {
    if(e.getSource()==clearb)
    {
      result.setText(" ");
      op1.setText("0");
      op2.setText("0");
    }else
    if(e.getSource()==calc)
    {
      int sum,x,y;
      String s1=op1.getText().trim();
      String s2=op2.getText().trim();
      String temps;
      x=Integer.parseInt(s1);
      y=Integer.parseInt(s2);
      sum=x+y;
      result.setText(String.valueOf(x)+"+"+String.valueOf(y)+"="+String.valueOf(sum));
    }
  }
  public static void main(String arg[])
  {
    (new calculator()).show();
  }
}
class WinClose implements WindowListener
{
  public void windowClosing(WindowEvent e)
  {
    System.exit(0);
  }
  public void windowOpened(WindowEvent e){};
  public void windowIconified(WindowEvent e){};
  public void windowDeiconifide(WindowEvent e){};
  public void windowClosed(WindowEvent e){};
  public void windowActivated(WindowEvent e){};
  public void windowDeactivated(WindowEvent e){};
};

import java.awt.Button;
import java.awt.Color;
import java.awt.FlowLayout;
import java.awt.Frame;
import java.awt.Label;
import java.awt.Panel;
import java.awt.TextField;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.WindowEvent;
import java.awt.event.WindowListener;

public class Calculator implements ActionListener {//这个地方应该使用大写,这是基本的常识.
    Frame f;

    Panel p1, p2;

    TextField op1, op2, result;

    Button calc, clearb;

    public void show() {
        f = new Frame("一个简单的计算器");
        f.setSize(240, 180);
        f.setLocation(300, 200);
        f.setBackground(Color.lightGray);
        f.setLayout(new FlowLayout());
        result = new TextField(20);
        result.setEditable(false);
        op1 = new TextField("0", 4);
        op2 = new TextField("0", 4);
        p1 = new Panel();
        p1.add(op1);
        p1.add(new Label("+"));
        p1.add(op2);
        f.add(result);
        f.add(p1);
        calc = new Button("=");
        clearb = new Button("Clear");
        p2 = new Panel();
        p2.add(calc);
        p2.add(clearb);
        f.add(p2);
        calc.addActionListener(this);
        clearb.addActionListener(this);
        f.addWindowListener(new WinClose());
        f.setVisible(true);
    }

    public void actionPerformed(ActionEvent e) {//这个地方应该是大写
        if (e.getSource() == clearb) {
            result.setText(" ");
            op1.setText("0");
            op2.setText("0");
        } else if (e.getSource() == calc) {
            int sum, x, y;
            String s1 = op1.getText().trim();
            String s2 = op2.getText().trim();
            String temps;
            x = Integer.parseInt(s1);
            y = Integer.parseInt(s2);
            sum = x + y;
            result.setText(String.valueOf(x) + "+" + String.valueOf(y) + "="
                    + String.valueOf(sum));
        }
    }

    public static void main(String arg[]) {
        (new Calculator()).show();
    }
}

class WinClose implements WindowListener {
    public void windowClosing(WindowEvent e) {
        System.exit(0);
    }

    public void windowOpened(WindowEvent e) {
    };

    public void windowIconified(WindowEvent e) {
    };

    public void windowDeiconified(WindowEvent e) {//这个地方写颠倒了.
    };

    public void windowClosed(WindowEvent e) {
    };

    public void windowActivated(WindowEvent e) {
    };

    public void windowDeactivated(WindowEvent e) {
    };
};