Mockito stubbing thenAnswer抛出空指针异常

我对Mockito相当陌生，我试图编写一个测试用例，我需要控制返回值，所以我使用Mockito提供的“thenAnswer”方法。但是我遇到java.lang.NullPointerException，我无法弄清楚为什么。下面是我的示例代码：Mockito stubbing thenAnswer抛出空指针异常

@Before 
    public void setUp() throws Exception { 
    customerFactory = Mockito.mock(CustomerFactory.class); 
    contactChecker = new ContactChecker(); 
    } 

    @After 
    public void tearDown() throws Exception { 
    customerFactory = null; 
    contactChecker = null; 
    } 

    @Test 
    public void testRetryGetContactFromCDS() { 
    Mockito.when(customerFactory.getContactByAccountId(Mockito.anyString())).thenAnswer(new Answer<Contact>() { 
     @Override 
     public Contact answer(InvocationOnMock invocation) throws Throwable { 
     Contact testContact = new Contact(); 
     contact.setId("12345"); 
     return testContact; 
     } 
    }); 
    contactChecker.setCustomerFactory(customerFactory); 
    assertNotNull(contactChecker.retryGetContactFromCDS("stringThatDoesNotMatter")); 
    }

CutomerFactory有一个名为getContactByAccountId方法，我用客户厂ContactChecker类，如下所示：

public class ContactChecker { 
    private CustomerFactory customerFactory; 
    private static final int MAX_RETRY_TIME = 300000; // 5 mins. We give CDS 5 mins to create record we are looking for. 
    long startTimeForCDSContactChecking = System.currentTimeMillis(); 
    long currentTime; 
    public CustomerFactory getCustomerFactory() { 
    return customerFactory; 
    } 
    public void setCustomerFactory(CustomerFactory customerFactory) { 
    this.customerFactory = customerFactory; 
    } 
    public String retryGetContactFromCDS(String webProfileId) { 
    currentTime = System.currentTimeMillis(); 
    String contactId = null; 
    while((currentTime - startTimeForCDSContactChecking)/1000 < MAX_RETRY_TIME) { 
     //Keep trying to get cds contact id 
     Contact contact = customerFactory.getContactByAccountId(webProfileId); 
     if (contact != null) { 
     contactId = contact.getId(); 
     break; 
     } 
     currentTime = System.currentTimeMillis(); 
    } 
    return contactId; 
    }

什么可能我做错了吗？对于JUnit测试的完整的堆栈跟踪是：

java.lang.NullPointerException 
    at com.internal.licensing.consumer.ContactCheckerTest$1.answer(ContactCheckerTest.java:38) 
    at com.internal.licensing.consumer.ContactCheckerTest$1.answer(ContactCheckerTest.java:1) 
    at org.mockito.internal.stubbing.StubbedInvocationMatcher.answer(StubbedInvocationMatcher.java:31) 
    at org.mockito.internal.MockHandler.handle(MockHandler.java:92) 
    at org.mockito.internal.creation.MethodInterceptorFilter.intercept(MethodInterceptorFilter.java:47) 
    at com.internal.business.license.customer.CustomerFactory$$EnhancerByMockitoWithCGLIB$$b9ace21e.getContactByMathWorksAccountId(<generated>) 
    at com.internal.licensing.consumer.ContactChecker.retryGetContactFromCDS(ContactChecker.java:22) 
    at com.internal.licensing.consumer.ContactCheckerTest.testRetryGetContactFromCDS(ContactCheckerTest.java:43) 
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) 
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) 
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) 
    at java.lang.reflect.Method.invoke(Method.java:601) 
    at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:44) 
    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:15) 
    at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:41) 
    at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:20) 
    at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:28) 
    at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:31) 
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:76) 
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:50) 
    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:193) 
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:52) 
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:191) 
    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:42) 
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:184) 
    at org.junit.runners.ParentRunner.run(ParentRunner.java:236) 
    at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:50) 
    at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38) 
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:467) 
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683) 
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390) 
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197)

来源

2013-11-25 tsure

什么是在第38行'ContactCheckerTest.java：38'？ –

public Contact answer(InvocationOnMock invocation) throws Throwable { 
    Contact testContact = new Contact(); 
    contact.setId("12345"); 
    return testContact; 
    }

变化contact到testContact

来源

2013-11-25 14:06:27

Mockito stubbing thenAnswer抛出空指针异常

回答

相关问题