本案例要求利用Java Swing 图形组件开发一个可以进行简单的四则运算的图形化计算器。

好的，这是一个简单的四则运算的图形化计算器，可以进行加、减、乘、除四则运算。您可以输入两个数，并选择运算符，点击“计算”按钮，即可得到结果。以下是示例代码：

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

public class Calculator extends JFrame {

    private JTextField num1Field, num2Field, resultField;
    private JComboBox<String> operatorBox;

    public Calculator() {
        super("Calculator");

        //设置窗口大小和位置
        setSize(300, 200);
        setLocationRelativeTo(null);

        //设置布局
        setLayout(new GridLayout(4, 2));

        //添加组件
        add(new JLabel("Number 1:"));
        num1Field = new JTextField();
        add(num1Field);

        add(new JLabel("Number 2:"));
        num2Field = new JTextField();
        add(num2Field);

        add(new JLabel("Operator:"));
        operatorBox = new JComboBox<>(new String[]{"+", "-", "*", "/"});
        add(operatorBox);

        add(new JLabel("Result:"));
        resultField = new JTextField();
        resultField.setEditable(false);
        add(resultField);

        JButton calcButton = new JButton("Calculate");
        //添加计算按钮的事件监听
        calcButton.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                //获取用户输入的数值和运算符
                double num1 = Double.parseDouble(num1Field.getText().trim());
                double num2 = Double.parseDouble(num2Field.getText().trim());
                String operator = (String) operatorBox.getSelectedItem();

                //进行四则运算
                double result;
                switch (operator) {
                    case "+":
                        result = num1 + num2;
                        break;
                    case "-":
                        result = num1 - num2;
                        break;
                    case "*":
                        result = num1 * num2;
                        break;
                    case "/":
                        result = num1 / num2;
                        break;
                    default:
                        result = 0;
                }

                //将结果显示到结果文本框中
                resultField.setText(Double.toString(result));
            }
        });
        add(calcButton);

        setVisible(true);
    }

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

运行程序，即可看到界面如下所示：