Junit4测试Calculator

Calculator代码：

package cn.itcast;

import org.junit.Before;

public class Calculator {
    private static int result; // 静态变量，用于存储运行结果
    public void add(int n) {
        result = result + n;
    }
    public void substract(int n) {
        result = result - 1; //故意的Bug，应该是 result =result-n
    }
    public void multiply(int n) {
    } // 假设此方法在项目完成过程中尚未写好
    public void divide(int n) {
        result = result / n;
    }
    public void square(int n) {
        result = n * n;
    }
    public void squareRoot(int n) { //求平方根
        for (; ;) ; //Bug : 死循环
    }
    public void clear() { // 将结果清零
        result = 0;
    }
    public int getResult(){
        return result;
    }
}

创建Test，在class处按shift+ctrl+T进行创建

 Test代码：

package cn.itcast;

import org.junit.Ignore;
import org.junit.Test;

import static org.junit.Assert.*;

public class CalculatorTest {
    Calculator calculator = new Calculator();
    @Test
    public void add() {
        calculator.add(10);
        assertEquals(calculator.getResult(),10);
    }

    @Test
    public void substract() {
        calculator.add(10);
        calculator.substract(10);
        assertEquals(calculator.getResult(),0);
    }

    @Ignore("该方法未实现")
    public void multiply() {
        calculator.multiply(10);
    }

    @Test
    public void divide() {
        calculator.divide(0);
    }

    @Test
    public void square() {
        calculator.square(10);
        assertEquals(calculator.getResult(),100);
    }

    @Test(timeout = 2000)
    public void squareRoot() {
        calculator.squareRoot(4);
        assertEquals(calculator.getResult(),2);
    }

    @Test
    public void clear() {
        calculator.clear();
        assertEquals(calculator.getResult(),0);
    }

}

运行后可以查看是否通过测试