How to use shouldNotFindAnySuspiciousMatchersWhenNumberOfArgumentsDoesntMatch method of org.mockito.internal.verification.argumentmatching.ArgumentMatchingToolTest class

This code works fine. To set static field you need to pass a class to org.powermock.reflect.Whitebox.setInternalState. Please, ensure that you use PowerMock's class from the package org.powermock.reflect because Mockito has the class with the same name.

 @RunWith(PowerMockRunner.class)
 public class UtilitiesTest {

    @Mock
    private Logger.ALogger aLogger;

    @Before
    public void setUp() throws Exception {

        MockitoAnnotations.initMocks(this); // for case them used another runner
        Whitebox.setInternalState(CcpProcessorUtilities.class, "LOGGER", aLogger);
    }

    @Test
    public void testLogger() throws Exception {
        Utilities.convertToURl("");
        verify(aLogger).error(eq("Invalid Format"), any(IllegalArgumentException.class));
    }
}

Mockito has an isNull matcher, where you can pass in the name of the class. So if you need to use it with other matchers, the correct thing to do is

verify(client).method(eq("String"),isNull(Class<?>.class));

This is now deprecated, see the answer below for the new method - https://stackoverflow.com/a/41250852/1348

Further reading has led me to try using ArgumentCaptors and the following works, although much more verbose than I would like.

ArgumentCaptor<String> argument = ArgumentCaptor.forClass(String.class);

verify(errors, atLeastOnce()).add(argument.capture(), any(ActionMessage.class));

List<String> values = argument.getAllValues();

assertTrue(values.contains("exception.message"));
assertTrue(values.contains("exception.detail"));

You could solve this by two ways.

Using Mock:

Page<TaskEntity> tasks = Mockito.mock(Page.class);
Mockito.when(this.taskRepository.findAll(org.mockito.Matchers.isA(Pageable.class))).thenReturn(tasks);

Or, Using class instantiation:

List<TaskEntity> tasks = new ArrayList<>();
Page<TaskEntity> pagedTasks = new PageImpl(tasks);
Mockito.when(this.taskRepository.findAll(pagedTasks)).thenReturn(pagedTasks);

You can use a spy.

public class MyVideoService {

  private VideoService videoService;

  public MyVideoService(VideoService videoService) {
    this.videoService = videoService;
  }

  public void delete(String param) {
    videoService.deleteVideo(param);
  }
}

public class VideoService {
  public void deleteVideo(String param) {
  }
}

If you now want to test an object that uses MyVideoService. E.g.

public class ObjectThatUsesMyVideoService {

  private MyVideoService myVideoService;

  ObjectThatUsesMyVideoService(MyVideoService myVideoService) {
    this.myVideoService = myVideoService;
  }

  public void deleteVideo(String param) {
    myVideoService.delete(param);
  }
}

You can write a test like this

public class MyVideoServiceTest {

  @Test
  public void delete(){
    // VideoService is just a mock
    VideoService videoServiceMock = Mockito.mock(VideoService.class); 

    // Creating the real MyVideoService
    MyVideoService myVideoService = new MyVideoService(videoServiceMock);

    // Creating a spy proxy
    MyVideoService myVideoServiceSpy = Mockito.spy(myVideoService);

    ObjectThatUsesMyVideoService underTest = new ObjectThatUsesMyVideoService(myVideoServiceSpy);

    underTest .deleteVideo("SomeValue");

    // Verify that myVideoService was invoked
    Mockito.verify(myVideoServiceSpy, Mockito.times(1)).delete("SomeValue");

    // Verify that myVideoService invoked the VideoService
    Mockito.verify(videoServiceMock, Mockito.times(1)).deleteVideo("SomeValue");
  }
}

This is because you are not using the SpringJUnitClassRunner.

Mockito and your own classes are not taking the @Retryable annotation in account. So you rely on the implementation of Spring to do so. But your test does not activate Spring.

This is from the SpringJUnit4ClassRunner JavaDoc:

SpringJUnit4ClassRunner is a custom extension of JUnit's BlockJUnit4ClassRunner which provides functionality of the Spring TestContext Framework to standard JUnit tests by means of the TestContextManager and associated support classes and annotations. To use this class, simply annotate a JUnit 4 based test class with @RunWith(SpringJUnit4ClassRunner.class) or @RunWith(SpringRunner.class).

You should restructure your test class at least to something like:

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(classes=MyConfig.class)
public class MyServiceTest {
    @Configuration
    @EnableRetry
    @Import(myService.class)
    public static class MyConfig {}
...

What am I doing there?

1. activate the Spring JUnit hook
2. specify the Spring context configuration class
3. define the spring configuration and import your service as a bean
4. enable the retryable annotation

Are there some other pitfalls?

• Yes, you are using Mockito to simulate an exception. If you want to test this behaviour with Spring like this, you should have a look at Springockito Annotations.
• But be aware of that: Springockito you will replace the spring bean completely which forces you to proxy the call of your retryable. You need a structure like: test -> retryableService -> exceptionThrowingBean. Then you can use Springockito or what ever you like e.g. ReflectionTestUtils to configure the exceptionThrowingBean with the behaviour you like.
• You should reference the interface type of your service in your test: MyServiceInterface
• And last but not least. There is a naming convention nearly all Java developers follow: class names have first letter of each internal word capitalized

Hope that helps.

To test the lambdas behavior, the underlayingApi has to be mocked where the lambda is invoked via the InvoactionOnMock object like this.

    `when`(underlayingApi.post(eq("some/rest/url"),
                               any())).thenAnswer {
        val argument = it.arguments[1]
        val completion = argument as ((rawResult: String?, exception: Exception?) -> Unit)
        completion.invoke("result", null)
    }

This leads to the invocation of the callback within the object under test. Now to check if the callback out of the object under test is working verify it like that.

    objUnderTest.loadData(id,
                          { json, exception ->
                              assert....
                          })

I had the same problem today. I'm not sure what happened, but by updating the compileSdkVersion, buildToolsVersion and targetSdkVersion to match the support-annotations version, the issue is gone.

Now the build.gradle looks like:

android {
  compileSdkVersion 27
  buildToolsVersion "27.0.2"

  defaultConfig {
    ...
    targetSdkVersion 27
  }
}

dependencies {
  compile 'com.android.support:support-annotations:27.0.2'
  androidTestCompile 'com.android.support:support-annotations:27.0.2'
}

I couldn't find much comments about it, so I hope I can help someone.

After a lot of painful Maven trial & error I struggled across this website, which provides a surprisingly easy way to use unit-tests in a Maven-Tycho setup.

Here, the important parts of the pom.xml when using JUnit (probably looks similar for Mockito):

<testSourceDirectory>src/test/java</testSourceDirectory>
<dependencies>
    <dependency>
        <groupId>junit</groupId>
        <artifactId>junit</artifactId>
        <version>4.11</version>
        <scope>test</scope>
    </dependency>
</dependencies>
<plugins>
  <plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-surefire-plugin</artifactId>
    <version>2.12.4</version>
    <executions>
      <execution>
        <id>test</id>
        <phase>test</phase>
        <configuration>
          <includes>
            <include>**/*Test.java</include>
          </includes>
        </configuration>
        <goals>
          <goal>test</goal>
        </goals>
      </execution>
    </executions>
  </plugin>

  <plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-compiler-plugin</artifactId>
    <version>2.5.1</version>
    <executions>
      <execution>
        <id>compiletests</id>
        <phase>test-compile</phase>
        <goals>
          <goal>testCompile</goal>
        </goals>
      </execution>
    </executions>
  </plugin>
</plugins>

Name all your tests in a way so that they end with *Test.java. Run mvn test in order to execute all available unit-tests.