当从控制器类调用服务类方法时，SpringMVC-Mockito-Junit-NullPointerException

Question

我正在使用springMVC编写一个web应用程序。我制作了一个服务类，用于使用UI将事物映射到数据库和从数据库映射事物。

我的问题是我是junit和mockito的新手当我试图在Controller类上编写单元测试时，它总是返回一个NullPointerException。这真的很烦人，因为我找不到答案，所以我希望你们能帮我。下面我发布了我的代码。

我的控制器类方法打开/更新返回成功

@RequestMapping(value = "/update", method = RequestMethod.POST)
    public String updateFormData(@ModelAttribute CRDetails certGuide,
            ModelMap model) { 
        crService.updateCertification(certGuide);
        return "success";   
}

My Service类方法使用修改后的数据更新mongodb

public void updateCertification(CRDetails certGuide) {      String userTypeSubmitted = certGuide.getCertGuidelines().getUserType();         System.out.println("updated by " + userTypeSubmitted);      Update update = new Update();       Query query = new Query(Criteria.where("cr").is("CR1"));
        CRDetails details = certMongoTemplate.findOne(query, CRDetails.class,
                COLLECTION_NAME);       CertificateGuidelines newCertGuide = new CertificateGuidelines();
        if (details != null) {          newCertGuide.setCertG(certGuide.getCertGuidelines().getCertG());            if (userTypeSubmitted.equals("Certification Team")
                    && userTypeSubmitted != "") {
                newCertGuide.setStatus("Pending with Document Developer");          } else {
                newCertGuide.setStatus("Pending with Certification Team");          }           newCertGuide.setHistoryCount(++count);
            // converting it into mongo document.           MongoConverter converter = certMongoTemplate.getConverter();            DBObject newRec = (DBObject) converter
                    .convertToMongoType(newCertGuide);          update.set("certGuidelines", newRec);       }
        System.out.println("new cert guide " + newCertGuide.getCertG() + " "
                + newCertGuide.getStatus() + " "
                + newCertGuide.getHistoryCount() + " "
                + newCertGuide.getUserType());
                certMongoTemplate.updateFirst(query, update, CRDetails.class); }

我的控制器测试返回NullPointerException的类。

import static org.junit.Assert.assertEquals;
import org.junit.Before; 
import org.junit.Test; 
import org.mockito.InjectMocks; 
import org.mockito.Mock;  
import org.mockito.Mockito; 
import org.springframework.test.web.server.MockMvc; 
import org.springframework.ui.ModelMap; 
import org.springframework.web.servlet.View;
import com.cerner.docworks.controller.CRController; 
import com.cerner.docworks.domain.CRDetails; 
import com.cerner.docworks.service.CRService;

public class CRControllerTest  {
    /*@Mock     private CRService service;*/
    @Mock   View mockView;
   @InjectMocks      
   private CRController crController;
    private MockMvc mockMvc;
     @Before     public void setup() {
             }
    @Test   public void testUpdate() throws Exception {          //     CRService service = Mockito.mock(CRService.class);      CRService crService = Mockito.spy(new CRService());         ModelMap model = Mockito.mock(ModelMap.class);      CRDetails certGuide = Mockito.spy(new CRDetails());
                CRController controller = new CRController();
                 //     Mockito.when(service.updateCertification(certGuide)); //        Mockito.when(model.addAttribute(Matchers.eq("certGuide"),any(String.class))).thenReturn(null); //       Mockito.doThrow(new RuntimeException()).when(crService).updateCertification(certGuide);         Mockito.doNothing().when(crService).updateCertification(certGuide);         Mockito.mockingDetails(certGuide); //       Mockito.doCallRealMethod().when(crService).updateCertification(certGuide); //       Mockito.(crService)).updateCertification(certGuide);;       String fileName = controller.updateFormData(certGuide, model);
                System.out.println(fileName); //        Mockito.verify(controller).updateFormData(certGuide, model);        assertEquals("success", fileName);  } }

跟踪：

位于的java.lang.NullPointerExceptioncom.cerner.docworks.controller.CRController.updateFormData（CRController.java:81）在com.cerner.docworks.controller.test.CRControllerTest.testUpdate（CRControlollerTest.java:62）位于的sun.reflect.NativeMethodAccessorImpl.invoke0（本机方法）sun.reflect.NativeMethodAccessorImpl.invoke（NativeMethodAccessorImpl.java:62）在sun.reflect.DelegatingMethodAccessorImpl.invoke（DelegatingMethodAccessorImpl.java:43）位于java.lang.reflect.Method.ioke（Method.java:483）org.junit.runners.model.FrameworkMethod$1.runReflectiveCall（FrameworkMethod.java:50）在org.junit.internal.runners.model.ReflectiveCallable.run（ReflectiveCallable.java:12）在org.junit.runners.model.FrameworkMethod.invokeExploly（FrameworkMethod.java:47）在org.junit.internal.runners.statements.InvokeMethod.eevaluate（InvokeMethod.java:17）在org.junit.internal.runners.statements.RunBefores.evaluate（RunBefores.java:26）网址：org.junit.runners.ParentRunner.runLeaf（ParentRunner:java:325）org.junit.runners.BlockJUnit4ClassRunner.runChild（BlockJUnit4ClassRunner.java:78）在org.junit.runners.BlockJUnit4ClassRunner.runChild（BlockJUnit4ClassRunner.java:57）网址：org.junit.runners.ParentRunner$3.run（ParentRunner.java:290）org.junit.runners.ParentRunner$1.schedule（ParentRunner.java:71）org.junit.runners.ParentRunner.runChildren（ParentRunner:288）org.junit.runners.ParentRunner.access$000（ParentRunner:58），网址：org.junit.runners.ParentRunner$2.eevaluate（ParentRunner.java:268）org.junit.runners.ParentRunner.run（ParentRunner:363）org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run（JUnit4TtestReference.java:50）在org.eclipse.jdt.internal.junit.runner.TestExecution.run（TestExecution.java:38）在org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests（RemoteTestRunner.java:459）在org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests（RemoteTestRunner.java:675）在org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run（RemoteTestRunner.java:382）在org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main（RemoteTestRunner.java:192）

FYI，CRDetails是一个带有的pojo类

private String id;
    private String cr;
    private String desc;
    private CertificateGuidelines certGuidelines;
    private Date dueDate;
    //private String userType;
    private String solutionName;

FYI，当我调试代码时，我发现mock正在将对象设置为null如果我手动设置细节，测试用例通过，但是，我想使用mockito。

提前感谢您的帮助。

Answer 1

您需要使用MockitoJUnitRunner运行测试，例如：

@RunWith(MockitoJUnitRunner.class)
public class CRControllerTest {
     // ...

这允许@InjectMocks和@Mock正常工作。也就是说，mockView将被创建为View的模型，而crController将与相关的@Mock注释字段一起创建。

您可以参考文档来了解mock是如何注入的。