How can I mock an instance of an enum class with PowerMock & Mockito?

You need to run this with PowerMockRunner

eg.

@RunWith(PowerMockRunner.class)
@PrepareForTest({ ExampleEnumerable.class})
@Test(groups = {"LoadableBuilderTestGroup"})
public class LoadableBuilderTest {
    private ExampleEnumerable mockEnumerable;

    @BeforeMethod
    public void setUp() {
        mockEnumerable = mock(ExampleEnumerable.class);
    }
}

I got this working by extending the PowerMockTestCase class that handles this kind of thing for TestNG:

@PrepareForTest(TestEnumerable.class)
@Test(groups = {"LoadableBuilderTestGroup"})
public class LoadableBuilderTest extends PowerMockTestCase {

 private TestEnumerable mockEnumerable;

 @SuppressWarnings("unchecked")
    @BeforeMethod
    public void setUp() {
        mockEnumerable = PowerMockito.mock(TestEnumerable.class);

    }
}