前提：pom引用 
         
     
      junit
          
     
      junit
          
     
      4.12
      
    

         
     
      org.springframework
          
     
      spring-test
          
     
      4.0.5.RELEASE
          
     
      test
      
     
         
     
      org.mockito
          
     
      mockito-all
          
     
      1.10.19
      
     背景: 方便后台开发自测接口，去除对象之间的复杂依赖，关注代码逻辑的正确性。 原理： Mockito就是用Java提供的Dynamic Proxy API来实现的。 以下是简单的小demo:

package com.mock; import org.junit.runner.RunWith; import org.springframework.test.context.ContextConfiguration; import org.springframework.test.context.TestExecutionListeners; import org.springframework.test.context.junit4.SpringJUnit4ClassRunner; import org.springframework.test.context.support.DependencyInjectionTestExecutionListener; import org.springframework.test.context.transaction.TransactionalTestExecutionListener; /**  * 所以测试类的基类  *  * @author tom_plus  * @date 2017-01-02-17:20  */ @ContextConfiguration(locations = {"classpath:applicationContext-test.xml"}) @RunWith(SpringJUnit4ClassRunner.class) @TestExecutionListeners(listeners = {DependencyInjectionTestExecutionListener.class,         TransactionalTestExecutionListener.class}) public class AbstractServiceIT {
  }

package com.mock.demo; import com.AopTargetUtils; import com.mock.AbstractServiceIT; import com.springapp.bean.Teacher; import com.springapp.service.TeacherService; import com.springapp.service.TestService; import com.springapp.utils.SessionContext; import org.junit.Before; import org.junit.Test; import org.mockito.Mock; import org.mockito.MockitoAnnotations; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.test.util.ReflectionTestUtils; import org.springframework.transaction.annotation.Transactional; import org.testng.Assert; import java.util.List; import static org.mockito.Matchers.*; import static org.mockito.Mockito.*; /**  * mock 使用demo  * 一个强大的用于 Java 开发的模拟测试框架  *  * @author tom_plus  * @date 2017-01-02-17:45  */ public class MockServiceIT extends AbstractServiceIT{
      @Mock     SessionContext sessionContext;     @Autowired     private TestService testService;     @Before     public void befTest() {
          MockitoAnnotations.initMocks(this);         when(sessionContext.getId()).thenReturn(3);         try {
              ReflectionTestUtils.setField(AopTargetUtils.getTarget(testService), "sessionContext", sessionContext);         } catch (Exception e) {
              e.printStackTrace();         }     }     @Test     @Transactional     public void updateIT() throws Exception {
          Teacher teacher = new Teacher();         teacher.settName("樱木花道");         int j = testService.update2(teacher);         System.out.println("result:"+j);         Assert.assertEquals(j,1,"更新成功");     }     /**      * 参数匹配器，一旦使用参数匹配器，则方法中必须处处使用参数匹配器      */     @Test     public void argumentMatcherTest(){
          List
    
      list = mock(List.class);         when(list.get(anyInt())).thenReturn("hello","world");         String result = list.get(0)+list.get(1);         System.out.println(result);         //verify 方法验证mock 对象的互动次数         verify(list,times(2)).get(anyInt());         verify(list,atLeast(2)).get(anyInt());         Assert.assertEquals("helloworld", result);     }     /**      * 使用异常处理void 方法      */     @Test     public void stubbingForVoidMethod() {
          List
     
       list = mock(List.class);         doThrow(new RuntimeException("you are clear a list!")).when(list).clear();         list.clear();     } }
     
    

package com; import org.springframework.aop.framework.AdvisedSupport; import org.springframework.aop.framework.AopProxy; import org.springframework.aop.support.AopUtils; import java.lang.reflect.Field; /**  * Created by tom_plus on 2017/1/2.  */ public class AopTargetUtils {
      /**      * 获取 目标对象      *      * @param proxy 代理对象      * @throws Exception 默认spring中Service对象是代理对象，不能直接把值设置到属性上，所以我们自己写个小的工具类      */     public static Object getTarget(Object proxy) throws Exception {
          if (!AopUtils.isAopProxy(proxy)) {
              return proxy;//不是代理对象         }         //jdk         if (AopUtils.isJdkDynamicProxy(proxy)) {
              return getJdkDynamicProxyTargetObject(proxy);         } else { //cglib             return getCglibProxyTargetObject(proxy);         }     }     private static Object getCglibProxyTargetObject(Object proxy) throws Exception {
          Field h = proxy.getClass().getDeclaredField("CGLIB$CALLBACK_0");//获得字节码文件中的MethodInterceptor cglib$CALLBACK_0 变量         h.setAccessible(true);         Object dynamicAdvisedInterceptor = h.get(proxy);         Field advised = dynamicAdvisedInterceptor.getClass().getDeclaredField("advised");         advised.setAccessible(true);         Object target = ((AdvisedSupport) advised.get(dynamicAdvisedInterceptor)).getTargetSource().getTarget();         return target;     }     private static Object getJdkDynamicProxyTargetObject(Object proxy) throws Exception {
          Field h = proxy.getClass().getSuperclass().getDeclaredField("h");         h.setAccessible(true);         AopProxy aopProxy = (AopProxy) h.get(proxy);         Field advised = aopProxy.getClass().getDeclaredField("advised");         advised.setAccessible(true);         Object target = ((AdvisedSupport) advised.get(aopProxy)).getTargetSource().getTarget();         return target;     } }