Q:

Mockito 2 + Junit 5 NoSuchMethodError on AnnotationSupport.findAnnotation

I'm trying to integrate JUnit 5 under Eclipse Oxygen3.
The project already has Mockito 2.
I have done all steps suggested in https://www.baeldung.com/mockito-junit-5-extension like so:
Dependencies:

junit-jupiter-engine 5.5.0
junit-jupiter-api 5.5.0
junit-vintage-engine 5.5.0
junit-platform-runner 1.5.0
mockito-core 2.28.2
mockito-junit-jupiter 2.28.2

Code:
public class Jupiter {

    public boolean isAlpha() {
        return true;
    }

}

Test Code:
import static org.assertj.core.api.Assertions.assertThat;
import static org.mockito.BDDMockito.given; 
import java.util.Date;  
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.DisplayName;
import org.junit.jupiter.api.Test;
import org.junit.jupiter.api.extension.ExtendWith;
import org.junit.platform.runner.JUnitPlatform;
import org.junit.runner.RunWith;
import org.mockito.InjectMocks;
import org.mockito.Mock;
import org.mockito.junit.jupiter.MockitoExtension;

@ExtendWith(MockitoExtension.class)
@RunWith(JUnitPlatform.class)
public class JupiterTest {

    @InjectMocks
    private Jupiter jupiter;

    @BeforeEach
    public void setup() {
        //usually some stuff here
    }

    @Test
    @DisplayName("heading jupiter - make it so")
    public void test() {
        boolean result = jupiter.isAlpha();

        assertThat(result).isTrue();
    }
}

Unfortunately, running tests fail. 
Have anyone stumbled upon a similar problem? Is it something general or my project specific problem?
java.lang.NoSuchMethodError: org.junit.platform.commons.support.AnnotationSupport.findAnnotation(Ljava/util/Optional;Ljava/lang/Class;)Ljava/util/Optional;
    at org.mockito.junit.jupiter.MockitoExtension.retrieveAnnotationFromTestClasses(MockitoExtension.java:178)
    at org.mockito.junit.jupiter.MockitoExtension.beforeEach(MockitoExtension.java:160)
    at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.lambda$null$0(TestMethodTestDescriptor.java:126)
...
Suppressed: java.lang.NullPointerException
    at org.mockito.junit.jupiter.MockitoExtension.afterEach(MockitoExtension.java:214)
    at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.lambda$null$11(TestMethodTestDescriptor.java:214)
    at org.junit.jupiter.engine.execution.ThrowableCollector.execute(ThrowableCollector.java:40)
    at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.lambda$invokeAllAfterMethodsOrCallbacks$13(TestMethodTestDescriptor.java:226)
    at java.util.ArrayList.forEach(ArrayList.java:1257)
    at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.invokeAllAfterMethodsOrCallbacks(TestMethodTestDescriptor.java:224)
    at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.invokeAfterEachCallbacks(TestMethodTestDescriptor.java:213)
    at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.execute(TestMethodTestDescriptor.java:116)
    ... 43 more

A:

Not sure why need all that vintage and platform stuff.. Your tests are org.junit.jupiter.api.Test;
I would do this:
1) Remove all the annotations from the class level
2) Init Mockito:
@BeforeEach
public void setup() {
    MockitoAnnotations.initMocks(this);
}

3) These deps should be sufficient:
junit-jupiter 5.5.0
mockito-core 2.28.2

