import junit.framework.TestCase;

 import junit.framework.Assert;

 /**

  *测试类必须要继承TestCase类

  *在junit3.8中，测试方法需要满足以下原则：

  *1、public

  *2。void

  *3.无方法参数

  *4.方法名称必须以test开头

  *执行每个测试用例前会调用setup方法，后会调用tearDown方法

  */

 public class CalculatorTest extends TestCase {

     private Calculator cal;

     public CalculatorTest(String name){

         super(name);

     }

     @Override

     public void setUp() throws Exception {

         cal=new Calculator();

     }

     public void testAdd(){

         int result=cal.add(2, 3);

         Assert.assertEquals(5, result);

     }

     public void testSubtract(){

         int result=cal.subtract(2, 3);

         Assert.assertEquals(-1, result);

     }

     public void testMutiply(){

         int result=cal.multiply(2, 3);

         Assert.assertEquals(6, result);

     }

     public void testDivide(){

         int result=0;

         try {

             result = cal.divide(6, 2);

         } catch (Exception e) {

             // TODO Auto-generated catch block

             e.printStackTrace();

             Assert.fail();

         }

         Assert.assertEquals(3, result);

     }

     /**

      * Throwable为错误和异常的父类

      */

     public void testDivideByZero(){

         Throwable tx=null;

         try {

             cal.divide(2, 0);

             Assert.fail();

         } catch (Exception e) {

             tx=e;

             e.printStackTrace();

         }

         Assert.assertEquals(Exception.class,tx.getClass());

         Assert.assertEquals("除数不能为0", tx.getMessage());

     }

 }

 import junit.extensions.RepeatedTest;

 import junit.framework.TestCase;

 import junit.framework.TestSuite;

 import junit.framework.Test;

 /**

  * 自动化测试

  *

  */

 public class TestAll extends TestCase {

     public static Test suite(){

         TestSuite suite=new TestSuite();

         suite.addTestSuite(CalculatorTest.class);

         suite.addTestSuite(LargestTest.class);

         suite.addTestSuite(DeleteAllTest.class);

         //重复执行CalculatorTest里的testAdd方法的次数

         suite.addTest(new RepeatedTest(new CalculatorTest("testAdd"), 20));

         return suite;

     }

 }