java简易计算器课设

以下是一个简易的Java计算器程序的示例：

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

public class Calculator extends JFrame implements ActionListener {
    private JTextField textField;
    private JButton[] buttons;
    private String[] buttonLabels = {
            "7", "8", "9", "/",
            "4", "5", "6", "*",
            "1", "2", "3", "-",
            "0", ".", "=", "+"
    };

    private double num1, num2, result;
    private char operator;

    public Calculator() {
        setTitle("简易计算器");
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setLayout(new BorderLayout());

        textField = new JTextField();
        textField.setHorizontalAlignment(JTextField.RIGHT);
        add(textField, BorderLayout.NORTH);

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

        buttons = new JButton[buttonLabels.length];
        for (int i = 0; i < buttonLabels.length; i++) {
            buttons[i] = new JButton(buttonLabels[i]);
            buttons[i].addActionListener(this);
            buttonPanel.add(buttons[i]);
        }

        add(buttonPanel, BorderLayout.CENTER);

        pack();
        setVisible(true);
    }

    public void actionPerformed(ActionEvent e) {
        String command = e.getActionCommand();

        if (command.matches("[0-9.]")) {
            textField.setText(textField.getText() + command);
        } else if (command.matches("[/*\\-+]")) {
            num1 = Double.parseDouble(textField.getText());
            operator = command.charAt(0);
            textField.setText("");
        } else if (command.equals("=")) {
            num2 = Double.parseDouble(textField.getText());
            switch (operator) {
                case '/':
                    result = num1 / num2;
                    break;
                case '*':
                    result = num1 * num2;
                    break;
                case '-':
                    result = num1 - num2;
                    break;
                case '+':
                    result = num1 + num2;
                    break;
            }
            textField.setText(String.valueOf(result));
        }
    }

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

这个程序使用了Java Swing库来创建一个简易的计算器界面。用户可以通过鼠标或键盘输入数字和运算符，然后计算器会显示结果。