Constructor Injection is not injecting Optional

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Having this code snippet:

@RunWith(MockitoJUnitRunner.class)
public class OptionalInjectionTest
{

    public static class Foo {}

    public static class Bar {
        private final Foo foo;
        public Bar(final Optional<Foo> foo) {
            System.out.println("Foo is "+foo);
            this.foo = foo.orElse(null);
        }
    	public Foo getFoo() {
            return foo;
        }
    }

    @Mock
    private Foo foo;

    @InjectMocks
    private Bar bar;

    @Test
    public void testInjectOptional()
    {
        assertNotNull(bar);
        assertNotNull(bar.getFoo());
    }
}

Running the test throws:

org.mockito.exceptions.misusing.InjectMocksException: 
Cannot instantiate @InjectMocks field named 'bar' of type 'class com.mycompany.app.OptionalInjectionTest$Bar'.
You haven't provided the instance at field declaration so I tried to construct the instance.
However the constructor or the initialization block threw an exception : null

Mockito injects null, while instead it should Inject Optional[foo] (or if Foo Mock is not found - empty Optional[])

Info: Mockito: 3.1.0 JDK: 1.8 OS: WIN10

[bric3]

What @TimvdLippe ment is this

	private Foo foo;
	private Bar bar;

	@Before
	public void setUp() {
                foo = mock(Foo.class);
		bar = new Bar(Optional.of(foo));
	}

[Praytic]

How can I do the same with annotations? I have a huge constructor with 20 values and 1 optional. Because of it I need to write this huge constructor in @Before method?