How to test a method invocation inside an anonymous class using mockito

Question

@Transactional(propagation = Propagation.REQUIRED)
    public void exe() {
        try {
            Reserve reserveInfo = newTransactionTemplate.execute(new TransactionCallback<Reserve>() {
                @Override
                public Reserve doInTransaction(TransactionStatus status) {
                    return reserveService.callReserve(reserveDetails);
                }
            });
            if(reserveInfo != null && reserveInfo.getStatus()=="DONE") {
            someOtherService.doSomething();
            }
        } finally {
            if(reserveInfo!= null && reserveInfo.getStatus().equals("DONE")){
                final String id = reserveInfo.getId();                                  
                Release releaseInfo = newTransactionTemplate.execute(new TransactionCallback<Release>() {
                    @Override
                    public Release doInTransaction(TransactionStatus status) {
                        return reserveService.callRelease(id);
                    }
                });             
                if (releaseInfo.getStatus() != "RELEASED") {
                    throw new RuntimeException("Problem in releaseing");

                }
            }
        }       
    }

This is the sample code I want to test. I couldn't find much on testing anonymous class on net. I want to test the exe() method, go through newTransactionTemplate.execute method and mock the call to reserveService.callReserve(reserveDetails).

Can any body please suggest how can I test this situation?

here is the sample how i'm trying to test:

 private SomeService someService = null;
    @Mock
    private ReserveService mockReserveService;
    @Mock
    private ReleaseService mockReleaseService;
    @Mock
    private TransactionTemplate mockTransactionTemplate;
    @Mock
    private SomeOtherService mockSomeOtherService;    
    @BeforeMethod
    public void setup() throws Exception {
       MockitoAnnotations.initMocks(this);   
       someService = new SomeService();
       someService.setReserveService(mockReserveService);
       someService.setReleaseService(mockReleaseService);
       someService.setSomeOtherService(mockSomeOtherService);
       someService.setNewTransactionTemplate(mockTransactionTemplate);
    }
    @Test(enabled=true)
    public void exeHappyPath() {
        Reserve reserveInfo = new Reserve();
        reserveInfo.setId("123");
        reserveInfo.setStatus("DONE");
        Release releaseInfo = new Release();
        releaseInfo.setStatus("RELEASED");
        when(mockReserveService.callReserve(Mockito.any(ReserveDetails.class))).thenReturn(reserveInfo);
        when(mockReserveService.callRelease(reserveInfo.getId())).thenReturn(releaseInfo);
        when(mockTransactionTemplate.execute(Mockito.<TransactionCallback<Reserve>>any())).thenReturn(reserveInfo);
        when(mockTransactionTemplate.execute(Mockito.<TransactionCallback<ReleaseInfo>>any())).thenReturn(releaseInfo);
        //Call the exe method
        someService.exe();

        verify(mockReserveService, times(1)).callReserve(Mockito.any(ReserveDetails.class));
        verify(mockReserveService, times(1)).callRelease(reserveInfo.getId())); 
        verify(mockSomeOtherService, times(1)).doSomthing());

    }

The second call to when(mockTransactionTemplate.execute.. with return object releaseInfo throws java.lang.ClassCastException:

Answer 1

Here is the solution to the above mentioned scenario. As I was not interested in testing the invocation of newTransactionTemplate.execute() , it being an spring API. I wanted to test the invocation of reserveService.callReserve(reserveDetails) and reserveService.callRelease(id) . The only way to test this is if we create a transactiontemplate/transactioncallback "real" implementation/stub that is just pass thru. so the doIntransaction method should do nothing more than execute the action. then we can set expectation on the action methods which in this case is the reserveService .

    when(mockTransactionTemplate.execute(Mockito.<TransactionCallback>any())).thenAnswer(new Answer() {
         public Object answer(InvocationOnMock invocation) {
             Object[] args = invocation.getArguments();
           TransactionCallback arg = (TransactionCallback)args[0];
             return arg.doInTransaction(new SimpleTransactionStatus());
         }
     });     
    when(mockResourceService.callReserve(any(ReserveDetails.class))).thenReturn(reserveInfo);
    when(mockResourceService.callRelease(eq(id))).thenReturn(releaseInfo);

    //Call the exe method
    someService.exe();

    verify(mockResourceService, times(1)).callReserve(any(ReserveDetails.class));
    verify(mockSomeOtherService, times(1)).doSomthing());
    verify(mockMemberResourceService, times(1)).callRelease(eq(id)); 

Answer 2

Where does reserveService come from? If you are injecting it through either SomeClass 's constructor or a setter, you can pass a mock instead.

// Set up your mock and stub out the method call
ReserveService reserveService = mock(ReserveService.class);
when(reserveService.callReserve(any(ReserveDetails.class))).thenReturn(null);

// Inject, either via constructor or setter
SomeClass instance = new SomeClass(reserveService);
// Or, instance.setReserveService(reserveService);