Mockito mock void methods Example

@RunWith(MockitoJUnitRunner.class)
public class StubbingTest {

    @Mock
    private  List list;

    @Before
    public void init() {
        list = mock(ArrayList.class);
    }


    @Test
    public void howToUseStubbing() {
        when(list.get(0)).thenReturn("first");
        assertThat(list.get(0), equalTo("first"));
        when(list.get(anyInt())).thenThrow(new RuntimeException());
        try {
            list.get(0);
            fail();
        } catch (Exception e) {
            assertThat(e, instanceOf(RuntimeException.class));
        }
    }

    @Test
    public void howToStubbingVoidMethod() {
        doNothing().when(list).clear();
        doThrow(RuntimeException.class).when(list).clear();
        try {
            list.clear();
            fail();
        } catch (Exception e) {
            assertThat(e, instanceOf(RuntimeException.class));
        }
    }

    @Test
    public void stubbingReturn() {
        when(list.get(0)).thenReturn("first");
        doReturn("second").when(list).get(1);
        assertThat(list.get(0), equalTo("first"));
        assertThat(list.get(1), equalTo("second"));
    }

    @Test
    public void stubbingWithAnswer() {
        when(list.get(anyInt())).thenAnswer(invocationOnMock -> {
            Integer index = invocationOnMock.getArgument(0, Integer.class);
            return String.valueOf(index * 10);
        });
        assertThat(list.get(0), equalTo("0"));
        assertThat(list.get(10), equalTo("100"));
        assertThat(list.get(999), equalTo("9990"));
    }

    @Test
    public void iterateSubbing() {
        when(list.size()).thenReturn(1, 2, 3, 4, 5);
        assertThat(list.size(), equalTo(1));
        assertThat(list.size(), equalTo(2));
        assertThat(list.size(), equalTo(3));
        assertThat(list.size(), equalTo(4));
        assertThat(list.size(), equalTo(5));
        assertThat(list.size(), equalTo(5));
    }

    @Test
    public void stubbingServiceTest() {
        StubbingService stubbingService = mock(StubbingService.class);
        System.out.println(stubbingService.getClass());
        stubbingService.gets();
    }

    @After
    public void destroy() {
        reset(this.list);
    }


}