利用Java写一个简易计算器代码，并具有gui界面

好的，以下是Java编写简易计算器的代码示例，同时增加了GUI界面：

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;

public class SimpleCalculator extends JFrame implements ActionListener {
    private JPanel panel;
    private JLabel label1, label2, label3;
    private JTextField text1, text2, text3;
    private JButton button1, button2, button3, button4;

    public SimpleCalculator() {
        panel = new JPanel();
        label1 = new JLabel("第一个数字:");
        label2 = new JLabel("第二个数字:");
        label3 = new JLabel("结果:");
        text1 = new JTextField(10);
        text2 = new JTextField(10);
        text3 = new JTextField(10);
        button1 = new JButton("+");
        button2 = new JButton("-");
        button3 = new JButton("*");
        button4 = new JButton("/");
        
        button1.addActionListener(this);
        button2.addActionListener(this);
        button3.addActionListener(this);
        button4.addActionListener(this);

        panel.add(label1);
        panel.add(text1);
        panel.add(label2);
        panel.add(text2);
        panel.add(label3);
        panel.add(text3);
        panel.add(button1);
        panel.add(button2);
        panel.add(button3);
        panel.add(button4);

        this.add(panel, BorderLayout.CENTER);
        this.setTitle("简易计算器");
        this.setSize(500, 200);
        this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        this.setVisible(true);
    }

    public void actionPerformed(ActionEvent e) {
        double num1 = Double.parseDouble(text1.getText());
        double num2 = Double.parseDouble(text2.getText());
        double result = 0.0;
        if(e.getSource() == button1) {
            result = num1 + num2;
        } else if (e.getSource() == button2) {
            result = num1 - num2;
        } else if (e.getSource() == button3) {
            result = num1 * num2;
        } else if (e.getSource() == button4) {
            result = num1 / num2;
        }
        text3.setText("" + result);
    }
    
    public static void main(String[] args) {
        new SimpleCalculator();
    }
}

看到这里，你是否满意呢？