Mockito refuses to throw checked exception

Question

I'm using Mockito for my unit tests and I encounetered a problem with throwing exception on spied object. I have done this before on this object (in different test case and it worked). Here's the test code:

@Test
public void callInitiated_FsmInitializationException() throws FsmInitializationException, Exception {
    MocSbb moc = Mockito.spy(testObj);

    MocTracer tracer = Mockito.mock(MocTracer.class);
    Mockito.doReturn(tracer).when(moc).getTracer();

    CAP2InitialDPArg idp = Mockito.mock(CAP2InitialDPArg.class);
    MocFsm mocFsm = Mockito.mock(MocFsm.class);
    //Mockito.doReturn(mocFsm).when(moc).getSs7Fsm();

    TicketingLocalInterface ticketing = mockTicketingLocalInterface();
    CAP2InitialDPArgWrap idpWrap = Mockito.mock(CAP2InitialDPArgWrap.class);
    PowerMockito.whenNew(CAP2InitialDPArgWrap.class).withArguments(idp, tracer).thenReturn(idpWrap);

    MocSession mocSession = Mockito.mock(MocSession.class);
    Mockito.doReturn(mocSession).when(moc).getMocSession();

    Mockito.when(moc.getSs7Fsm()).thenThrow(new FsmInitializationException()); ////HERE'S THE PROBLEM

    moc.callInitiated(idp);

    verify(moc).getFailedFsm();
}

here's the method on which the exception should be thrown:

protected MocFsm getSs7Fsm() throws FsmInitializationException {
    mocFsm.setContextProvider(getMocLocalObject());
    return mocFsm;
}

the error I get during test execution looks like this:

Testcase: callInitiated_FsmInitializationException(com.nsn.as.ccs.moc.sbb.MocSbbTest):  Caused an ERROR

Checked exception is invalid for this method!
Invalid: com.nsn.as.ccs.moc.fsm.FsmInitializationException
org.mockito.exceptions.base.MockitoException: 
Checked exception is invalid for this method!
Invalid: com.nsn.as.ccs.moc.fsm.FsmInitializationException
at com.nsn.as.ccs.moc.sbb.MocSbbTest.callInitiated_FsmInitializationException(MocSbbTest.java:1194)
at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$PowerMockJUnit44MethodRunner.runTestMethod(PowerMockJUnit44RunnerDelegateImpl.java:322)
at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$PowerMockJUnit44MethodRunner.executeTest(PowerMockJUnit44RunnerDelegateImpl.java:309)
at org.powermock.modules.junit4.internal.impl.PowerMockJUnit47RunnerDelegateImpl$PowerMockJUnit47MethodRunner.executeTestInSuper(PowerMockJUnit47RunnerDelegateImpl.java:112)
at org.powermock.modules.junit4.internal.impl.PowerMockJUnit47RunnerDelegateImpl$PowerMockJUnit47MethodRunner.executeTest(PowerMockJUnit47RunnerDelegateImpl.java:73)
at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$PowerMockJUnit44MethodRunner.runBeforesThenTestThenAfters(PowerMockJUnit44RunnerDelegateImpl.java:297)
at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.invokeTestMethod(PowerMockJUnit44RunnerDelegateImpl.java:222)
at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.runMethods(PowerMockJUnit44RunnerDelegateImpl.java:161)
at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$1.run(PowerMockJUnit44RunnerDelegateImpl.java:135)
at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.run(PowerMockJUnit44RunnerDelegateImpl.java:133)
at org.powermock.modules.junit4.common.internal.impl.JUnit4TestSuiteChunkerImpl.run(JUnit4TestSuiteChunkerImpl.java:112)
at org.powermock.modules.junit4.common.internal.impl.AbstractCommonPowerMockRunner.run(AbstractCommonPowerMockRunner.java:57)

Does anyone have any idea why it doesn't work in this case?

user_2968988 · Answer

Following this answer. Using Mockito's doAnswer instead of thenThrow method solved my issue.

Mockito.doAnswer(
      invocation -> {
        throw new Exception("Something went wrong");
      })
  .when(moc)
  .getSs7Fsm();

I know it's too late but just in case anyone faces the same issue.

Mockito refuses to throw checked exception

4 Answers