How to use shouldReplaceObjectMethods method of org.mockitousage.basicapi.ResetInvocationsTest class

What about creating a private method in your test that sets the common expectations on a given mock object?

Mocks that return have the expectation that the return type matches the mocked object's return type.

Here's the mistake:

Mockito.when(remoteStore.get("a", "b")).thenReturn("lol");

"lol" isn't an Optional<String>, so it won't accept that as a valid return value.

The reason it worked when you did

Optional<Object> returnCacheValue = Optional.of((Object) returnCacheValueString);
Mockito.<Optional<Object>>when(remotestore.get("cache-name", "cache-key")).thenReturn(returnCacheValue);

is due to returnCacheValue being an Optional.

This is easy to fix: just change it to an Optional.of("lol") instead.

Mockito.when(remoteStore.get("a", "b")).thenReturn(Optional.of("lol"));

You can also do away with the type witnesses as well. The result above will be inferred to be Optional<String>.

You're surprised that the writes on the new objects aren't writing through to the backing collection?

Collections.transform doesn't just do the transform "as needed" -- it doesn't store anything at all. That's what "view" means in its documentation. Any time you walk through a Collections2.transformed collection, it applies the function again, freshly. Once that for loop in the apply method is done with result, that object is gone; never seen again.

If you want to do what you're doing, make an explicit copy of the transformed collection in e.g. an ArrayList.

With Mockito framework, you can use AdditionalMatchers

ClassA classA = Mockito.mock(ClassA.class);
Mockito.when(classA.getString(Matchers.eq("a"))).thenReturn("something"); 
Mockito.when(classA.getString(AdditionalMatchers.not(Matchers.eq("a")))).thenReturn("something else");

Hope it helps.

You can absolutely inject mocks on MyLauncher in your test. I am sure if you show what mocking framework you are using someone would be quick to provide an answer. With mockito I would look into using @RunWith(MockitoJUnitRunner.class) and using annotations for myLauncher. It would look something like what is below.

@RunWith(MockitoJUnitRunner.class)
public class MyLauncherTest
    @InjectMocks
    private MyLauncher myLauncher = new MyLauncher();

    @Mock
    private MyService myService;

    @Test
    public void someTest() {

    }
}

In new Mockito versions you can use stubbing consecutive calls to throw exception on first can and returning a value on a second call.

when(mock.someMethod("some arg"))
    .thenThrow(new RuntimeException())
    .thenReturn("foo");

https://javadoc.io/doc/org.mockito/mockito-core/latest/org/mockito/Mockito.html#10

Try Mockito and you will love it!

You can have a look of this library in this blog post, showing 6 simple examples of Mockito usage.

A short example:

@Test
public void iteratorWillReturnHelloWorld(){
    //arrange
    Iterator i = mock(Iterator.class);
    when(i.next()).thenReturn("Hello").thenReturn("World");
    //act
    String result = i.next() + " " + i.next();
    //assert
    assertEquals("Hello World", result);
}

Edit regarding your requirements:

It seems that Mockito runs quite well on Java 1.4 and JUnit 3, as stated in this blog post.

The same example as above, but for Java 1.4:

public void testIteratorWillReturnHelloWorld(){
    //arrange
    Iterator i = Mockito.mock(Iterator.class);
    Mockito.when(i.next()).thenReturn("Hello").thenReturn("World");
    //act
    String result = i.next() + " " + i.next();
    //assert
    assertEquals("Hello World", result);
}

@Spy doc says:

A field annotated with @Spy can be initialized explicitly at declaration point. Alternatively, if you don't provide the instance Mockito will try to find zero argument constructor (even private) and create an instance for you.

@SpyBean doc says:

Annotation that can be used to apply Mockito spies to a Spring ApplicationContext.

All beans in the context of the same type will be wrapped with the spy. If no existing bean is defined a new one will be added.

So the main difference is @SpyBean is a Spring Boot specific annotation but @Spy is part of Mockito itself. @SpyBean and @Spy basically do the same, but @SpyBean can resolve the Spring specific dependencies, e.g. @Autowired, @Spy can only create object with empty constructor.

It seems that deprecated is void verify(VerificationMode mode, Verification verification) while void verify(Verification verification, VerificationMode mode) is still fine so you can just use the verify method like

dummyStatic.verify(
    () -> SomePublicClass.myPublicStaticFunc(anyInt()),
    times(1)
);

I've used the following dependency: testImplementation "org.mockito:mockito-inline:3.12.1".

It seems that with mockito-core you will not be able to mock this because you'll receive

The used MockMaker SubclassByteBuddyMockMaker does not support the creation of static mocks