安装并使用Junit

package com.calculator;

public class Cal {
    public int add(int a,int b)
    {
        return a+b;
    }
    public int minus(int a,int b)
    {
        return a-b;
    }
    public int multiply(int a,int b)
    {
        return a*b;
    }
    public int divide(int a,int b)
    {
        return a/b;
    }
}

package com.calculator;

import static org.junit.Assert.*;
import junit.framework.Assert;

import org.junit.Test;

public class CalTest extends Cal {

    @Test
    public void testAdd() {
        Cal c=new Cal();//实例化对象
        int result=c.add(3, 4);
        Assert.assertEquals(7, result);
        //fail("尚未实现");
    }

    @Test
    public void testMinus() {
        Cal c=new Cal();
        int result=c.minus(3, 1);
        Assert.assertEquals(2, result);
        //fail("尚未实现");
    }

    @Test
    public void testMultiply() {
        Cal c=new Cal();
        int result=c.multiply(2, 3);
        Assert.assertEquals(6, result);
        //fail("尚未实现");
    }

    @Test
    public void testDivide() {
        Cal c=new Cal();
        int result=c.divide(6,2);
        Assert.assertEquals(3, result);
        //fail("尚未实现");
    }

}