[Java] Can Mockito capture arguments of a method called multiple times?


Since Mockito 2.0 there's also possibility to use static method Matchers.argThat(ArgumentMatcher). With the help of Java 8 it is now much cleaner and more readable to write:

verify(mockBar).doSth(argThat((arg) -> arg.getSurname().equals("OneSurname")));
verify(mockBar).doSth(argThat((arg) -> arg.getSurname().equals("AnotherSurname")));

If you're tied to lower Java version there's also not-that-bad:

verify(mockBar).doSth(argThat(new ArgumentMatcher<Employee>() {
        public boolean matches(Object emp) {
            return ((Employee) emp).getSurname().equals("SomeSurname");

Of course none of those can verify order of calls - for which you should use InOrder :

InOrder inOrder = inOrder(mockBar);

inOrder.verify(mockBar).doSth(argThat((arg) -> arg.getSurname().equals("FirstSurname")));
inOrder.verify(mockBar).doSth(argThat((arg) -> arg.getSurname().equals("SecondSurname")));

Please take a look at mockito-java8 project which makes possible to make calls such as:

verify(mockBar).doSth(assertArg(arg -> assertThat(arg.getSurname()).isEqualTo("Surname")));

I have a method that gets called twice, and I want to capture the argument of the second method call.

Here's what I've tried:

ArgumentCaptor<Foo> firstFooCaptor = ArgumentCaptor.forClass(Foo.class);
ArgumentCaptor<Foo> secondFooCaptor = ArgumentCaptor.forClass(Foo.class);
// then do some assertions on secondFooCaptor.getValue()

But I get a TooManyActualInvocations Exception, as Mockito thinks that doSomething should only be called once.

How can I verify the argument of the second call of doSomething?

You can also use @Captor annotated ArgumentCaptor. For example:

List<String> mockedList;

ArgumentCaptor<String> argCaptor;

public void shouldCallAddMethodTwice() {
    Mockito.verify(mockedList, times(2)).add(argCaptor.capture());

    assertEquals("one", argCaptor.getAllValues().get(0));
    assertEquals("two", argCaptor.getAllValues().get(1));