import java.awt.*;

import java.awt.event.*;

import javax.swing.*;

import java.io.*;

import java.math.*;

import java.util.*;

/**

 * <p>Title: 用户应用界面计算器</p>

 * <p>Description: 包含简易计算与功能更加强大的科学计算</p>

 * <p>Copyright: Copyright (c) 2008</p>

 * <p>Company: 四川大学×××学院</p>

 * @author 陈文聪

 * @version 1.0

 */

 

public class Calculat {

  static JTextField show;//设置输入区，显示区

  static double opNum = 0;//存放操作数

  static String opChar = "=";//存放操作符

  static boolean flag = true;//设置标志

  public static void main(String[] args) {

    new EasyFrame();//产生首界面——简易计算器

  }

}

详情点击

[url=http://qxbs.blog.hexun.com/27923364_d.html]http://qxbs.blog.hexun.com/27923364_d.html[/url]
是我曾经的一个课程设计

谢谢诶

import java.awt.BorderLayout;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;

public class Computer extends JFrame implements ActionListener{
    
    private JTextField Number1;
    private JTextField Number2;
    private JTextField Result;
    private JLabel market;//选择运算符
    private JLabel equale;//==
    private JButton BResult;
    private JButton Add;
    private JButton Subtract;
    private JButton Multiply;
    private JButton Divide;
    
    public Computer(){
        this.setSize(350, 180);
        this.setTitle("计算器");
        this.setDefaultCloseOperation(EXIT_ON_CLOSE);
        initGUI();
    }
    
           
    public void initGUI(){
        
        JPanel p1 = new JPanel(new FlowLayout(FlowLayout.RIGHT));
        Number1 = new JTextField(8);    
        Number2 = new JTextField(8);
        Result = new JTextField(8);
        Result.setText("0.0");
        market = new JLabel("  ");
        equale = new JLabel("=");
        BResult = new JButton("Result");        
        p1.add(Number1);
        p1.add(market);
        p1.add(Number2);
        p1.add(equale);
        p1.add(Result);
        p1.add(BResult);
        BResult.addActionListener(this);
        
        JPanel p2 = new JPanel(new FlowLayout(FlowLayout.CENTER,25,10));
        Add = new JButton("+");
        Subtract = new JButton("-");
        Multiply = new JButton("*");
        Divide = new JButton("/");
        p2.add(Add);
        p2.add(Subtract);
        p2.add(Multiply);
        p2.add(Divide);
        add(p1,BorderLayout.CENTER);
        add(p2,BorderLayout.SOUTH);
        Add.addActionListener(this);
        Subtract.addActionListener(this);
        Multiply.addActionListener(this);
        Divide.addActionListener(this);
    }
    
    public void go(){
        this.setVisible(true);
    }

    @Override
    public void actionPerformed(ActionEvent e) {
        
        if(e.getSource().equals(Add)){
            market.setText("+");
        }
        if(e.getSource().equals(Subtract)){
            market.setText("-");
        }
        if(e.getSource().equals(Multiply)){
            market.setText("*");
        }
        if(e.getSource().equals(Divide)){
            market.setText("/");
        }
        
        if(e.getSource().equals(BResult)){
            double n1 = Double.parseDouble(Number1.getText());
            double n2 = Double.parseDouble(Number2.getText());
            if(market.getText().equals("+")){
                Result.setText(String.valueOf(n1+n2));
            }
            if(market.getText().equals("-")){
                Result.setText(String.valueOf(n1-n2));
            }
            if(market.getText().equals("*")){
                if(Number2.getText().equals(0))
                    Result.setText("Infinity");
                else
                    Result.setText(String.valueOf(n1*n2));
            }
            if(market.getText().equals("/")){
                Result.setText(String.valueOf(n1/n2));
            }
        }
    }
    
    public static void main(String args[]){
        Computer c = new Computer();
        c.go();
    }

    
}