（实验一）两个数字计算器（双精度浮点型）

主类Demo:

package com.cxy.test1.test;

import java.util.Scanner;

public class Demo {

/**
* @param args

*作者：陈星宇
*/
public static void main(String[] args) {

Calculator cal = new Calculator();
Scanner input = new Scanner(System.in);
System.out.print("请输入第一个数字:");
double num1 = input.nextDouble();
cal.setNum1(num1);
System.out.print("请输入符号:");
String sign = input.next();
cal.setSign(sign);
System.out.print("请输入第二个数字:");
double num2 = input.nextDouble();
cal.setNum2(num2);
cal.cal();

}

}

 

//Calculator类

package com.cxy.test1.test;

public class Calculator {

private double num1;
private double num2;
private String sign;

public double getNum1() {
return num1;
}

public void setNum1(double num1) {
this.num1 = num1;
}

public double getNum2() {
return num2;
}

public void setNum2(double num2) {
this.num2 = num2;
}

public String getSign() {
return sign;
}

public void setSign(String sign) {
this.sign = sign;
}

public void cal() {
if ("+".equals(getSign())) {
System.out.print("计算结果为:" + (num1 + num2));
} else if ("-".equals(getSign())) {
System.out.print("计算结果为:" + (num1 - num2));
} else if ("*".equals(getSign())) {
System.out.print("计算结果为:" + (num1 * num2));
} else if ("/".equals(getSign())) {
System.out.print("计算结果为:" + (num1 / num2));
} else {
System.out.println("对不起，你的输入有误");
}
}
}