How to use any_matcher method of org.mockitousage.matchers.CustomMatcherDoesYieldCCETest class

You could extract a method for doing the actual reading and then test that instead. That would mean you only have to mock a single reader. For example, your code would be something like this:

public void aMethod(){
    File f = map.get("key1")
    BuffereReader r = new BufferedReader(new FileReader(f));
    readStuff(r);
}

public void readStuff(BufferedReader r){
    String line=null;
    do {
        line=r.readLine();
    } while(r!=null);
}

then your test code would be more like the following:

BufferedReader bufferedReader = Mockito.mock(BufferedReader.class);
Mockito.when(bufferedReader.readLine()).thenReturn("line1", "line2", "line3");
objUnderTest.readStuff(bufferedReader);
//verify result

Adding an answer for newer versions of Mockito and Java 8

when(
   mock.method(argThat(t -> t.containsAll(Arrays.asList(IN_PROGRESS, ABANDONED, EXPIRED))))
).thenReturn(myValue);

There's no API for that at that time. You can try to code your own verifier code using MockingDetails.getInvocations

Mockito.mockingDetails(mock).getInvocations()

From the link you posted;

Default answer of every Mockito mock.

• Returns appropriate primitive for primitive-returning methods
• Returns consistent values for primitive wrapper classes (e.g. int-returning method retuns 0 and Integer-returning method returns 0, too)
• Returns empty collection for collection-returning methods (works for most commonly used collection types)
• Returns description of mock for toString() method
• Returns null for everything else

From the FAQ:

What values do mocks return by default?

In order to be transparent and unobtrusive all Mockito mocks by default return 'nice' values. For example: zeros, falseys, empty collections or nulls.

It was probably done to stay consistent with any other methods which return null for any other non-collection, non-primitive Wrapper objects.

You can always implement your own Answer to pass to mock which returns empty strings for String returning methods.

Try anyInt():

when(candidateService.findById(anyInt())).thenReturn(new Candidate());

For example I have anyLong() in my project:

when(dao.getAddress(anyLong())).thenReturn(Arrays.asList(dto));

EDIT: You must import:

import static org.mockito.Matchers.anyInt;

The two syntaxes for stubbing are roughly equivalent. However, you can always use doReturn/when for stubbing; but there are cases where you can't use when/thenReturn. Stubbing void methods is one such. Others include use with Mockito spies, and stubbing the same method more than once.

One thing that when/thenReturn gives you, that doReturn/when doesn't, is type-checking of the value that you're returning, at compile time. However, I believe this is of almost no value - if you've got the type wrong, you'll find out as soon as you run your test.

I strongly recommend only using doReturn/when. There is no point in learning two syntaxes when one will do.

You may wish to refer to my answer at Forming Mockito "grammars" - a more detailed answer to a very closely related question.

You can use PowerMockito

See the example:

Second second = Mockito.mock(Second.class);
whenNew(Second.class).withNoArguments().thenReturn(second);

But re-factoring is better decision.

Check the Java API for List.
The get(int index) method is declared to throw only the IndexOutOfBoundException which extends RuntimeException.
You are trying to tell Mockito to throw an exception SomeException() that is not valid to be thrown by that particular method call.

To clarify further.
The List interface does not provide for a checked Exception to be thrown from the get(int index) method and that is why Mockito is failing.
When you create the mocked List, Mockito will use the definition of List.class to creates its mock.

The behavior you are specifying with the when(list.get(0)).thenThrow(new SomeException()) doesn't match the method signature in List API, because get(int index) method does not throw SomeException() so Mockito fails.

If you really want to do this, then have Mockito throw a new RuntimeException() or even better throw a new ArrayIndexOutOfBoundsException() since the API specifies that that is the only valid Exception to be thrown.

Just incase any M1 Mac users stumble onto this page like I did.

My Issue -

My spring boot project with wiremock tests, would run on my old intel mac but failed to run when I moved to my new M1 Mac.

_ _

I had 2 error messages

• java.lang.IllegalStateException: No Server ALPNProcessors!
• Suppressed: java.lang.UnsatisfiedLinkError: no conscrypt_openjdk_jni-osx-aarch_64

Fix -

I needed a property to test.application

wiremock.server.httpsPort=-1