java编写一个简单计算器的界面

以下是一个简单的计算器界面的 Java 代码示例：

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

public class Calculator extends JFrame {
    private JTextField display;
    private JButton button1, button2, button3, button4, button5, button6, button7, button8, button9, button0, buttonPlus, buttonMinus, buttonMultiply, buttonDivide, buttonEquals;

    public Calculator() {
        super("Calculator");
        setSize(300, 400);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setLayout(new BorderLayout());

        display = new JTextField("");
        display.setHorizontalAlignment(JTextField.RIGHT);
        display.setEditable(false);
        add(display, BorderLayout.NORTH);

        JPanel buttonPanel = new JPanel();
        buttonPanel.setLayout(new GridLayout(4, 4));

        button7 = new JButton("7");
        buttonPanel.add(button7);

        button8 = new JButton("8");
        buttonPanel.add(button8);

        button9 = new JButton("9");
        buttonPanel.add(button9);

        buttonPlus = new JButton("+");
        buttonPanel.add(buttonPlus);

        button4 = new JButton("4");
        buttonPanel.add(button4);

        button5 = new JButton("5");
        buttonPanel.add(button5);

        button6 = new JButton("6");
        buttonPanel.add(button6);

        buttonMinus = new JButton("-");
        buttonPanel.add(buttonMinus);

        button1 = new JButton("1");
        buttonPanel.add(button1);

        button2 = new JButton("2");
        buttonPanel.add(button2);

        button3 = new JButton("3");
        buttonPanel.add(button3);

        buttonMultiply = new JButton("*");
        buttonPanel.add(buttonMultiply);

        button0 = new JButton("0");
        buttonPanel.add(button0);

        buttonEquals = new JButton("=");
        buttonPanel.add(buttonEquals);

        buttonDivide = new JButton("/");
        buttonPanel.add(buttonDivide);

        add(buttonPanel, BorderLayout.CENTER);
        setVisible(true);
    }

    public static void main(String[] args) {
        Calculator calculator = new Calculator();
    }
}

这个界面有一个文本框和一个包含数字和操作符按钮的面板。你可以在需要的位置添加事件监听器来实现计算器的功能。