How to use MockitoSessionLogger class of org.mockito.session package

A better way to accomplish that would probably be:

when(someService.someMethod(id)).thenThrow(new AccountNotFoundException());

then the compiler should infer the type correctly.

If someService.someMethod(id) has return type void you can do:

doThrow(new AccountNotFoundException()).when(someService).someMethod(id);

Please refer to the official Mockito documentation for examples like this using thenThrow. The documentation is very clear on this point.

You can also check the following StackOverflow question which is very similar (if not an exact duplicate):

How to mock and assert a thrown exception

You're misunderstanding what a mock is. When you're doing

MyClass myClass = Mockito.mock(MyClass.class);
// ...
assertNull(myClass.methodToTest(myObject));

You're not actually invoking methodToTest on your real object. You're invoking methodToTest on the mock, which by default, does nothing and return null, unless it was stubbed. Quoting from Mockito docs:

By default, for all methods that return value, mock returns null, an empty collection or appropriate primitive/primitive wrapper value (e.g: 0, false, ... for int/Integer, boolean/Boolean, ...).

This explains your subsequent error: the method was really not invoked on the mock.

It seems what you want here is a spy instead:

You can create spies of real objects. When you use the spy then the real methods are called (unless a method was stubbed).

A note of warning though: since it is the real methods that are getting called, you should not use Mockito.when but prefer Mockito.doReturn(...).when, otherwise the method will be called once for real. If you consider the expression:

Mockito.when(myClass.methodUsedInMethodBeingTested(Matchers.any(MyTypeParam.class))).thenReturn(Collections.<X, Y> emptyMap());
             ^-----------------------------------^
                 this will be invoked by Java

the argument of the method when must be evaluated, but this means the method methodUsedInMethodBeingTested will be invoked. And since we have a spy, it is the real method that will be invoked. So, instead, use:

MyClass spy = Mockito.spy(new MyClass());
Mockito.doReturn(Collections.<X, Y> emptyMap()).when(spy).methodUsedInMethodBeingTested(Matchers.any(MyTypeParam.class));
assertNull(spy.methodToTest(myObject));
Mockito.verify(spy).methodUsedInMethodBeingTested(Matchers.any(MyTypeParam.class));

I think the reason may be that mock object libraries typically create mocks by dynamically creating classes at runtime (using cglib). This means they either implement an interface at runtime (that's what EasyMock does if I'm not mistaken), or they inherit from the class to mock (that's what Mockito does if I'm not mistaken). Both approaches do not work for static members, since you can't override them using inheritance.

The only way to mock statics is to modify a class' byte code at runtime, which I suppose is a little more involved than inheritance.

That's my guess at it, for what it's worth...

The problem is that you are creating a mock of BaseManager but only BaseManagerImpl has a SessionFactory field. Mockito doesn't know about BaseManagerImpl. In your code you create two mocks which are completely independent of each other.

Unit tests are about testing an unit. So you should test BaseManagerImpl and RegistrationManagerImpl separately.

So you test BaseManagerImpl first:

public class BaseManagerImplTest {

    private BaseManagerImpl target;

    // ...
}

then you test RegistrationManagerImpl:

public class RegistrationManagerImplTest {

    private RegistrationManagerImpl target;

    // ...
}

I suggest that you should use the name target or something similar for your test target in your test class becaues it will make your code much more easier to read.

Another thing: If you test an object all of its dependencies should be mocked but you shouldn't care about the mocks' dependencies. You just mock their method invocations like:

Mockito.when(myMock.someMethod()).thenReturn(someResultObject);

Mockito can handle chained stubs:

Foo mock = mock(Foo.class, RETURNS_DEEP_STUBS);

// note that we're stubbing a chain of methods here: getBar().getName()
when(mock.getBar().getName()).thenReturn("deep");

// note that we're chaining method calls: getBar().getName()
assertEquals("deep", mock.getBar().getName());

AFAIK, the first method in the chain returns a mock, which is set up to return your value on the second chained method call.

Mockito's authors note that this should only be used for legacy code. A better thing to do otherwise is to push the behavior into your CacheContext and provide any information it needs to do the job itself. The amount of information you're pulling from CacheContext suggests that your class has feature envy.

If you use the MockitoJUnitRunner to run your test, then an ArgumentCaptor will be created for you, and there's no need to initialise it explicitly. If you do that, then you can also use the @Mock annotation to create your mock objects, that is, you don't need the mock static method any more. Your test class would then begin like this.

@RunWith(MockitoJUnitRunner.class)
public class WidgetStatusServletTest {

    @Captor private ArgumentCaptor<ArrayList<WidgetStatus>> captor;
    @Mock private DBController mockController;
    @Mock private HttpServletRequest mockRequest;
    @Mock private HttpServletResponse mockResponse;
    @Mock private Repository mockRepository;

This question addresses the issue of whether to use MockitoJUnitRunner, or an explicit call to MockitoAnnotations.initMocks.

Just a side note - your test methods will be much easier to read if you use variable names that clearly indicate that your objects are mocks, like I've done here. Otherwise, in a long test class with many different variables, it's easy to lose track of which variables reference mocks, and which reference "real" objects.

I don't quite follow what problem you're having using Mockito. Assuming you create a mock of the interface that contains your myMethod() method, you can then verify only the parameters to the method that you are interested in. For example (assuming the interface is called MyInterface and using JUnit 4):

@Test
public void test() {
    MyInterface myInterface = mock(MyInterface.class);
    FooBar expectedFooBar = new FooBar();        

    // other testing stuff

    verify(myInterface).myMethod(any(), any(), eq(expectedFooBar), any(), ...);
}

You'll need to do a static import on the Mockito methods for this to work. The any() matcher doesn't care what value has been passed when verifying.

You can't avoid passing something for every argument in your method (even if it's only NULL).

The problem with using RETURN_DEEP_STUBS is that you'll get a different mock each time you call a method. I think from your question that you want to use a default Answer that actually returns the mock on which it was called, for each method that has the right return type. This could look something like the following. Note that I haven't tested this, so it may contain typos, but I hope that the intention is clear in any case.

import static org.mockito.Mockito.RETURNS_DEFAULTS;
import org.mockito.invocation.InvocationOnMock;
import org.mockito.stubbing.Answer;

public class SelfReturningAnswer implements Answer<Object> {

    public Object answer(InvocationOnMock invocation) throws Throwable {
        Object mock = invocation.getMock();
        if(invocation.getMethod().getReturnType().isInstance(mock)){
            return mock;
        }
        return RETURNS_DEFAULTS.answer(invocation);
    }
}

Then, when you create your mock, specify this as your default answer. This will make your mock return itself from each method that it can; but it will behave like an ordinary mock when you call a method whose return type is wrong for the mock.

Create your mock like this

Builder mockBuilder = mock( Builder.class, new SelfReturningAnswer());

or create a constant for this class and write something like

@Mock(answer = SELF_RETURNING) private Builder mockBuilder;

Hope that helps.

An alternative to ArgumentMatcher is ArgumentCaptor.

Official example:

ArgumentCaptor<Person> argument = ArgumentCaptor.forClass(Person.class);
verify(mock).doSomething(argument.capture());
assertEquals("John", argument.getValue().getName());

A captor can also be defined using the @Captor annotation:

@Captor ArgumentCaptor<Person> captor;
//... MockitoAnnotations.initMocks(this);
@Test public void test() {
    //...
    verify(mock).doSomething(captor.capture());
    assertEquals("John", captor.getValue().getName());
}