Mockito MissingMethodInvocationException

Question

I am aware that there is a number of questions/answers similar for my question but I am still unable to resolve this issue with my testings.

Problem: I am trying to mock the Settings class but Mockito complains about this line:

when(settings.settingsBuilder().put(new String("test"), "test").build()).thenReturn(settings)

MissiongMethodInvocationException:

org.mockito.exceptions.misusing.MissingMethodInvocationException: 
when() requires an argument which has to be 'a method call on a mock'.
For example:
 when(mock.getArticles()).thenReturn(articles);

Also, this error might show up because:
1. you stub either of: final/private/equals()/hashCode() methods.
 Those methods *cannot* be stubbed/verified.
 Mocking methods declared on non-public parent classes is not supported.
2. inside when() you don't call method on mock but on some other object.

I've tried a number of possible ways but no results. Bellow is the actual testing method.

@RunWith(PowerMockRunner.class)
@PrepareForTest({Settings.class, Client.class})
public class AddressMatcherElasticTest {

private final AddressWebConfiguration configuration = mock(AddressWebConfiguration.class);
private final Settings settings = mock(Settings.class);
private final Client client = mock(Client.class);

  @Test
  public void match() throws Exception {
   when(configuration.getClusterName()).thenReturn(new String("name"));
   when(settings.settingsBuilder().put(new String("name"), "test").build()).thenReturn(settings);
   AddressMatcherElastic test = new AddressMatcherElastic(configuration);
   verify(configuration, times(1)).getClusterName();
 }
}

Solution

settings is your mock, and you can tell Mockito what to return if you invoke on it.

settings.settingsBuilder() does not return a mock, however, and that's what Mockito is complaining about. You can tell Mockito to return a mocked object when settingsBuilder is invoked e.g.

Builder settingsBuilder = mock(Builder.class);
when(settingsBuilder.doX()).thenReturn(...);
when(settings.settingsBuilder()).thenReturn(settingsBuilder);

Your mock will return null by default for an object reference if you don't declare otherwise, note.