Junit单元测试学习笔记（一）

l  使用方法

下载junit 

https://github.com/junit-team/junit/wiki/Download-and-Install 

    使用junit jar包

l 一个简单的test

  1.创建类

 public class calc {

	/**
	 * @param args
	 */
	public static int add(int first_num,int second_num)   //add method
       {
	       return  first_num+second_num;
       }
	public static int minus(int first_num,int second_num)   //minus method 
	    {
	    	return  first_num-second_num;
	    }
	public static int multiplication(int first_num,int second_num) //multiplication method
		{
			return  first_num*second_num;
		}
	public static int division(int first_num,int second_num)
		{
			return  first_num/second_num;  
            // division will throw ArithmeticException when the second_num=0
		}
	public static Boolean endless_loop()   //endless loop
	{
		for(;;);                             //junit time out 
		 
	}
	 
}

　　

2.创建test case

TestCase类给我们提供了setUp方法和tearDown方法，setUp方法的内容在测试你编写的TestCase子类的每个testXxxx方法之前都会运行，而tearDown方法的内容在每个testXxxx方法结束以后都会执行。

我们创建setUp方法：

import static org.junit.Assert.*;
import org.junit.Before;
import org.junit.Ignore;
import org.junit.Rule;
import org.junit.Test;
 

public class calcTest {

	@Test
	public void testAdd() {
		assertEquals(5, calc.add(2,3)); 
		
	}

	@Test
	public void testMunius() {
		assertEquals(5, calc.minus(2,3));
	}
	@Ignore("testMultiplication() Not yet implemented") //ignore this case
	@Test
	public void testMultiplication() {
		assertEquals(6, calc.multiplication(2,3));
	}
	
 
	@Test(expected=ArithmeticException.class)  // catch ArithmeticException exception
	public void testDivision () throws Exception {
		assertEquals(-1, calc.division(2,0));
     }

	@Test(timeout = 10000)   //defined time out =10 seconds
	public void testEndless_loop() {
		assertTrue("true",calc.endless_loop()); // can’t return within 10 seconds
	}

}

　　

  3.结果

If add “@Ignore("testMultiplication() Not yet implemented") “  

Then the test case will be ignored.