JMockit 與spring的mock操作

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如今，我們的很多應用程序是基於Spring的，通過Spring IOC容器來管理我們的Java對象。所以這里單獨提出對Spring Bean如何Mock方法。

以上述提到如何Mock類中的提到的AnOrdinaryClass為例，先把這個類配置在Spring的配置文件中

<?xml version="1.0" encoding="utf-8"?>
<!--suppress ALL -->
<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:context="http://www.springframework.org/schema/context"
    xmlns:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx"
    xmlns:p="http://www.springframework.org/schema/p"
    xsi:schemaLocation="http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans-2.5.xsd
        http://www.springframework.org/schema/context
        http://www.springframework.org/schema/context/spring-context-2.5.xsd
        http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-2.0.xsd
        http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-2.0.xsd"
    default-autowire="byName">
 
   <!-- 1個普通的spring bean-->
    <bean id="anOrdinaryBean" class="cn.jmockit.demos.AnOrdinaryClass" /> 
 
</beans>

同樣地，講述2種Mock方法

1. 用Expectations來Mock     

   //用Expectations來Mock Spring Bean
   @ContextConfiguration(locations = { "/META-INF/applicationContext1.xml" })
   @RunWith(SpringJUnit4ClassRunner.class)
   public class SpringBeanMockingByExpectationsTest {
       // 注入Spring Bean，Mock這個實例，就達到了Mock Spring Bean的目的
       @Resource
       AnOrdinaryClass anOrdinaryBean;
    
       @Test
       public void testSpringBeanMockingByExpectation() {
           // 直接把實例傳給Expectations的構造函數即可Mock這個實例
           new Expectations(anOrdinaryBean) {
               {
                   // 盡管這里也可以Mock靜態方法，但不推薦在這里寫。靜態方法的Mock應該是針對類的
                   // mock普通方法
                   anOrdinaryBean.ordinaryMethod();
                   result = 20;
                   // mock final方法
                   anOrdinaryBean.finalMethod();
                   result = 30;
                   // native, private方法無法用Expectations來Mock
               }
           };
           Assert.assertTrue(AnOrdinaryClass.staticMethod() == 1);
           Assert.assertTrue(anOrdinaryBean.ordinaryMethod() == 20);
           Assert.assertTrue(anOrdinaryBean.finalMethod() == 30);
           // 用Expectations無法mock native方法
           Assert.assertTrue(anOrdinaryBean.navtiveMethod() == 4);
           // 用Expectations無法mock private方法
           Assert.assertTrue(anOrdinaryBean.callPrivateMethod() == 5);
       }
    
       @BeforeClass    
       // 加載AnOrdinaryClass類的native方法的native實現    
       public static void loadNative() throws Throwable {    
           JNITools.loadNative();    
       }    
   }

   2.用MockUp來Mock

   //用MockUp來Mock Spring Bean
   @ContextConfiguration(locations = { "/META-INF/applicationContext1.xml" })
   @RunWith(SpringJUnit4ClassRunner.class)
   public class SpringBeanMockingByMockUpTest {
       // 注入Spring Bean，Mock這個實例，就達到了Mock Spring Bean的目的
       @Resource
       AnOrdinaryClass anOrdinaryBean;
    
       @Test
       public void testSpringBeanMockingByMockUp() {
           // 靜態方法被mock了
           Assert.assertTrue(AnOrdinaryClass.staticMethod() == 10);
           // 普通方法被mock了
           Assert.assertTrue(anOrdinaryBean.ordinaryMethod() == 20);
           // final方法被mock了
           Assert.assertTrue(anOrdinaryBean.finalMethod() == 30);
           // native方法被mock了
           Assert.assertTrue(anOrdinaryBean.navtiveMethod() == 40);
           // private方法被mock了
           Assert.assertTrue(anOrdinaryBean.callPrivateMethod() == 50);
       }
    
       @BeforeClass
       public static void beforeClassMethods() throws Throwable {
           loadNative();
           // 必須在Spring容器初始化前，就對Spring Bean的類做MockUp
           addMockUps();
       }
    
            
       // 加載AnOrdinaryClass類的native方法的native實現    
       public static void loadNative() throws Throwable {    
           JNITools.loadNative();    
       }    
    
       // 對AnOrdinaryClass的Class
       public static class AnOrdinaryClassMockUp extends MockUp<AnOrdinaryClass> {
           // Mock靜態方法
           @Mock
           public static int staticMethod() {
               return 10;
           }
    
           // Mock普通方法
           @Mock
           public int ordinaryMethod() {
               return 20;
           }
    
           @Mock
           // Mock final方法
           public final int finalMethod() {
               return 30;
           }
    
           // Mock native方法
           @Mock
           public int navtiveMethod() {
               return 40;
           }
    
           // Mock private方法
           @Mock
           private int privateMethod() {
               return 50;
           }
       }
    
       // 添加MockUp
       public static void addMockUps() {
           new AnOrdinaryClassMockUp();
       }
   }