JAVA

mockito when with void function

doAnswer(invocation -> {

      return null;
    }).when(object).method(any());

mockito when with void function

ArgumentCaptor<String> valueCapture = ArgumentCaptor.forClass(String.class);
doNothing().when(object).someMethod(string1, valueCapture.capture());

mockito mock void methods

Mockito.doThrow().when(mockObject).methodReturningVoid(any());

mockito mock static method

@Test
void givenStaticMethodWithNoArgs_whenMocked_thenReturnsMockSuccessfully() {
    assertThat(StaticUtils.name()).isEqualTo("Baeldung");

    try (MockedStatic<StaticUtils> utilities = Mockito.mockStatic(StaticUtils.class)) {
        utilities.when(StaticUtils::name).thenReturn("Eugen");
        assertThat(StaticUtils.name()).isEqualTo("Eugen");
    }

    assertThat(StaticUtils.name()).isEqualTo("Baeldung");
}

mockito method called

@Test
public void testDoFoo() {
  Bar bar = mock(Bar.class);
  BarFactory myFactory = new BarFactory() {
    public Bar createBar() { return bar;}
  };

  Foo foo = new Foo(myFactory);
  foo.foo();

  verify(bar, times(1)).someMethod();
}