How to use shouldReturnMutableEmptyCollection method of org.mockitousage.stubbing.StubbingWithThrowablesTest class

You should avoid creating business objects with new in a Spring application. You should always get them from the application context - it will ease mocking them in your test.

In your use case, you should simply create your validator as a bean (say defaultTerminationValidator) and inject it in your controller :

public class TerminationController extends AbstractController {

    private TerminationValidator terminationValidator;

    @Autowired
    public setDefaultTerminationValidator(TerminationValidator validator) {
        this.terminationValidator = validator;
    }

    @InitBinder("termination")
    public void initBinder(WebDataBinder binder, HttpServletRequest request) {
        binder.setValidator(terminationValidator);
        binder.setAllowedFields(new String[] { "termId[**]", "terminationDate",
                "accountSelection", "iban", "bic" });
    }

    [...]
}

That way, you will be able to simply inject a mock in your test.

Make sure the hamcrest jar is higher on the import order than your JUnit jar.

JUnit comes with its own org.hamcrest.Matcher class that is probably being used instead.

You can also download and use the junit-dep-4.10.jar instead which is JUnit without the hamcrest classes.

mockito also has the hamcrest classes in it as well, so you may need to move\reorder it as well

The code you posted works for me with the latest version of Mockito and Powermockito. Maybe you haven't prepared A? Try this:

A.java

public class A {
     private final String test;

    public A(String test) {
        this.test = test;
    }

    public String check() {
        return "checked " + this.test;
    }
}

MockA.java

import static org.hamcrest.MatcherAssert.assertThat;
import static org.hamcrest.Matchers.equalTo;
import static org.mockito.Mockito.mock;
import static org.mockito.Mockito.when;

import org.junit.Test;
import org.junit.runner.RunWith;
import org.mockito.Mockito;
import org.powermock.api.mockito.PowerMockito;
import org.powermock.core.classloader.annotations.PrepareForTest;
import org.powermock.modules.junit4.PowerMockRunner;

@RunWith(PowerMockRunner.class)
@PrepareForTest(A.class)
public class MockA {
    @Test
    public void test_not_mocked() throws Throwable {
        assertThat(new A("random string").check(), equalTo("checked random string"));
    }
    @Test
    public void test_mocked() throws Throwable {
         A a = mock(A.class); 
         when(a.check()).thenReturn("test");
         PowerMockito.whenNew(A.class).withArguments(Mockito.anyString()).thenReturn(a);
         assertThat(new A("random string").check(), equalTo("test"));
    }
}

Both tests should pass with mockito 1.9.0, powermockito 1.4.12 and junit 4.8.2

I got this to work by doing this in the test:

CompletableFuture<Long> future = new CompletableFuture<>();
future.completeExceptionally(new Exception("HTTP call failed!"));

Mockito.when(mockClient.getSize())
        .thenReturn(future);

Not sure if this is the best way though.

In my case, I had a similar issue when I worked with JUnit5

@ExtendWith(MockitoExtension.class)
class MyServiceTest {
...

@InjectMocks
MyService underTest;

@Test
void myMethodTest() {
...
}

underTest was null. The cause of the problem was that I used @Test from JUnit4 package import org.junit.Test; instead JUnit5 import org.junit.jupiter.api.Test;

Spring's MockRestServiceServer is exactly what you're looking for.

Short description from javadoc of the class:

Main entry point for client-side REST testing. Used for tests that involve direct or indirect (through client code) use of the RestTemplate. Provides a way to set up fine-grained expectations on the requests that will be performed through the RestTemplate and a way to define the responses to send back removing the need for an actual running server.

Try to set up your test like this:

@WebAppConfiguration
@ContextConfiguration(classes = {YourSpringConfig.class})
@RunWith(SpringJUnit4ClassRunner.class)
public class ExampleResourceTest {

    private MockMvc mockMvc;
    private MockRestServiceServer mockRestServiceServer;

    @Autowired
    private WebApplicationContext wac;

    @Autowired
    private RestOperations restOperations;

    @Before
    public void setUp() throws Exception {
        mockMvc = MockMvcBuilders.webAppContextSetup(this.wac).build();
        mockRestServiceServer = MockRestServiceServer.createServer((RestTemplate) restOperations);
    }


    @Test
    public void testMyApiCall() throws Exception {
        // Following line verifies that our code behind /api/my/endpoint made a REST PUT
        // with expected parameters to remote service successfully
        expectRestCallSuccess();

        this.mockMvc.perform(MockMvcRequestBuilders.get("/api/my/endpoint"))
            .andExpect(status().isOk());
    }

    private void expectRestCallSuccess() {
        mockRestServiceServer.expect(
            requestTo("http://remote.rest.service/api/resource"))
            .andExpect(method(PUT))
            .andRespond(withSuccess("{\"message\": \"hello\"}", APPLICATION_JSON));
    }


}

I would try any(byte[].class)

I had the same error but for me it was caused by the fact that I had ommited the ID as URL parameter. I ommited it because the ID was present in the JSON body.

When I changed .../restaurant to ...restaurant/1, the error went away.

Use PowerMockito on top of Mockito.

Example code:

@RunWith(PowerMockRunner.class)
@PrepareForTest(DriverManager.class)
public class Mocker {

    @Test
    public void shouldVerifyParameters() throws Exception {

        //given
        PowerMockito.mockStatic(DriverManager.class);
        BDDMockito.given(DriverManager.getConnection(...)).willReturn(...);

        //when
        sut.execute(); // System Under Test (sut)

        //then
        PowerMockito.verifyStatic();
        DriverManager.getConnection(...);

    }

More information:

• Why doesn't Mockito mock static methods?