作业5.2

package avshabi;

import java.util.StringTokenizer;

public class Calculator {

int numerator; // 分子

int denominator; // 分母

 

Calculator(){

}

 

Calculator(int a,int b){

if(a == 0){

numerator = 0;

denominator = 1;

}

else{

setNumeratorAndDenominator(a,b);

}

}

 

void setNumeratorAndDenominator(int a, int b){ // 设置分子和分母

int c = f(Math.abs(a),Math.abs(b)); // 计算最大公约数

numerator = a / c;

denominator = b / c;

if(numerator<0 && denominator<0){

numerator = - numerator;

denominator = - denominator;

}

}

 

int getNumerator(){

return numerator;

}

 

int getDenominator(){

return denominator;

}

 

int f(int a,int b){ // 求a和b的最大公约数

if(a < b){

int c = a;

a = b;

b = c;

}

int r = a % b;

while(r != 0){

a = b;

b = r;;

r = a % b;

}

return b;

}

 

Calculator add(Calculator r){ // 加法运算

int a = r.getNumerator();

int b = r.getDenominator();

int newNumerator = numerator * b + denominator * a;

int newDenominator = denominator * b;

Calculator result = new Calculator(newNumerator,newDenominator);

return result;

}

 

Calculator sub(Calculator r){ // 减法运算

int a = r.getNumerator();

int b = r.getDenominator();

int newNumerator = numerator * b - denominator * a;

int newDenominator = denominator * b;

Calculator result = new Calculator(newNumerator,newDenominator);

return result;

}

 

Calculator muti(Calculator r){ // 乘法运算

int a = r.getNumerator();

int b = r.getDenominator();

int newNumerator = numerator * a;

int newDenominator = denominator * b;

Calculator result = new Calculator(newNumerator,newDenominator);

return result;

}

 

Calculator div(Calculator r){ // 除法运算

int a = r.getNumerator();

int b = r.getDenominator();

int newNumerator = numerator * b;

int newDenominator = denominator * a;

Calculator result = new Calculator(newNumerator,newDenominator);

return result;

}

 

// 封装了具体运算，主要为对输入进行转换，对输出封装

public static void compute(String data1,String operation,String data2){

StringTokenizer fenxi = new StringTokenizer(data1,"/");

int data1_1 = Integer.parseInt(fenxi.nextToken());

int data1_2 = Integer.parseInt(fenxi.nextToken());

fenxi = new StringTokenizer(data2,"/");

int data2_1 = Integer.parseInt(fenxi.nextToken());

int data2_2 = Integer.parseInt(fenxi.nextToken());

 

Calculator r1 = new Calculator(data1_1,data1_2);

Calculator r2 = new Calculator(data2_1,data2_2);

 

Calculator result;

int a,b;

if(operation.equals("+")){

result = r1.add(r2);

a = result.getNumerator();

b = result.getDenominator();

System.out.println(data1+" "+operation+" " +data2+" = " + a + "/" + b);

}

 

if(operation.equals("-")){

result = r1.sub(r2);

a = result.getNumerator();

b = result.getDenominator();

System.out.println(data1+" "+operation+" " +data2+" = " + a + "/" + b);

}

 

if(operation.equals("*")){

result = r1.muti(r2);

a = result.getNumerator();

b = result.getDenominator();

System.out.println(data1+" "+operation+" " +data2+" = " + a + "/" + b);

}

 

if(operation.equals("/")){

result = r1.div(r2);

a = result.getNumerator();

b = result.getDenominator();

System.out.println(data1+" "+operation+" " +data2+" = " + a + "/" + b);

}

}

}

 

  

 

  

 

// 测试类

 

package avshabi;

 

import java.util.Scanner;

public class TestCal {

public static void main(String[] args) {

// TODO Auto-generated method stub

 

// 用户输入两分数和运算符

Scanner input = new Scanner(System.in);

System.out.println("请用户输入第一个分数(格式a/b)");

String data1 = input.next();

System.out.println("请用户输入要进行运算的运算符(+-*/)");

String operation = input.next();

System.out.println("请用户输入第二个分数(格式c/d)");

String data2 = input.next();

 

// 根据用户输入进行具体运算

Calculator cal = new Calculator();

System.out.println("运算结果为:");

cal.compute(data1, operation, data2);

//    }   

}

}

 

 

//JUint 应用测试举例

package avshabi;

 

import static org.junit.Assert.*;

 

import org.junit.Test;

 

public class CalculatorTest {

 

    @Test

    public void testAdd() {

        Calculator cal = new Calculator();

        cal.add(cal);

    }

 

    @Test

    public void testSub() {

        Calculator cal = new Calculator();

        cal.sub(cal);

    }

 

    @Test

    public void testMuti() {

        Calculator cal = new Calculator();

        cal.muti(cal);

    }

 

    @Test

    public void testDiv() {

        Calculator cal = new Calculator();

        cal.div(cal);

    }

 

    @Test

    public void testCompute() {

        Calculator cal = new Calculator();

        cal.compute("1/2", "+", "2/3");

        cal.compute("1/2", "-", "2/3");

        cal.compute("1/2", "*", "2/3");

        cal.compute("1/2", "/", "2/3");

    }