实现一个计算器，界面类似WINDOWS中的界面，包括0~9十个数字、加、减、乘、除四种运算符号和一个用于输入及显示结果的文本框，单击每个按钮都能完成相应的功能。-Implement a calculator, WINDOWS interface similar to the interface, including the ten digits 0 to 9, add, subtract, multiply and divide four arithmetic symbols and text

import java.awt.* import java.awt.event.* public class Calculator implements ActionListener { String s= " ",s1 double d1,d2 JFrame jf = new JFrame( "计算器 ") JTextField tf = new JTextField() public void init()//实现