How to use shouldNotPrintInvocationsWhenSingleUnwanted method of org.mockito.internal.exceptions.util.ScenarioPrinterTest class

Try View -> Tool Windows -> Maven projects, then click the blue icon in the top left of the tool window (Reimport all Maven projects). You should be able to find the dependencies in the project view, under external libraries.

If this does not work, there is probably something wrong with your maven config (pom.xml). Try mvn clean install from the command line see if it gives any errors.

Here is a good start using Mockito to test your UserDAO. This code uses a good amount of the Mockito features, so you can see how to use them. Let me know if you have questions.

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import javax.sql.DataSource;
import org.junit.After;
import org.junit.AfterClass;
import org.junit.Before;
import org.junit.BeforeClass;
import org.junit.Test;
import static org.junit.Assert.*;
import org.junit.runner.RunWith;
import static org.mockito.Matchers.anyInt;
import static org.mockito.Matchers.anyString;
import org.mockito.Mock;
import static org.mockito.Mockito.doNothing;
import static org.mockito.Mockito.times;
import static org.mockito.Mockito.verify;
import static org.mockito.Mockito.when;
import org.mockito.runners.MockitoJUnitRunner;

@RunWith(MockitoJUnitRunner.class)
public class TestUserDAO {

    @Mock
    DataSource mockDataSource;
    @Mock
    Connection mockConn;
    @Mock
    PreparedStatement mockPreparedStmnt;
    @Mock
    ResultSet mockResultSet;
    int userId = 100;

    public TestUserDAO() {
    }

    @BeforeClass
    public static void setUpClass() throws Exception {
    }

    @AfterClass
    public static void tearDownClass() {
    }

    @Before
    public void setUp() throws SQLException {
        when(mockDataSource.getConnection()).thenReturn(mockConn);
        when(mockDataSource.getConnection(anyString(), anyString())).thenReturn(mockConn);
        doNothing().when(mockConn).commit();
        when(mockConn.prepareStatement(anyString(), anyInt())).thenReturn(mockPreparedStmnt);
        doNothing().when(mockPreparedStmnt).setString(anyInt(), anyString());
        when(mockPreparedStmnt.execute()).thenReturn(Boolean.TRUE);
        when(mockPreparedStmnt.getGeneratedKeys()).thenReturn(mockResultSet);
        when(mockResultSet.next()).thenReturn(Boolean.TRUE, Boolean.FALSE);
        when(mockResultSet.getInt(Fields.GENERATED_KEYS)).thenReturn(userId);
    }

    @After
    public void tearDown() {
    }

    @Test
    public void testCreateWithNoExceptions() throws SQLException {

        UserDAO instance = new UserDAO(mockDataSource);
        instance.create(new User());

        //verify and assert
        verify(mockConn, times(1)).prepareStatement(anyString(), anyInt());
        verify(mockPreparedStmnt, times(6)).setString(anyInt(), anyString());
        verify(mockPreparedStmnt, times(1)).execute();
        verify(mockConn, times(1)).commit();
        verify(mockResultSet, times(2)).next();
        verify(mockResultSet, times(1)).getInt(Fields.GENERATED_KEYS);
    }

    @Test(expected = SQLException.class)
    public void testCreateWithPreparedStmntException() throws SQLException {

         //mock
         when(mockConn.prepareStatement(anyString(), anyInt())).thenThrow(new SQLException());


        try {
            UserDAO instance = new UserDAO(mockDataSource);
            instance.create(new User());
        } catch (SQLException se) {
            //verify and assert
            verify(mockConn, times(1)).prepareStatement(anyString(), anyInt());
            verify(mockPreparedStmnt, times(0)).setString(anyInt(), anyString());
            verify(mockPreparedStmnt, times(0)).execute();
            verify(mockConn, times(0)).commit();
            verify(mockResultSet, times(0)).next();
            verify(mockResultSet, times(0)).getInt(Fields.GENERATED_KEYS);
            throw se;
        }

    }
}

You need to inject the mock into the class which you are testing. You do not need access to Subscriber. The way mockito and other mocking frameworks help is that you do not need access to objects which you are interacting with. You do however need a way to get mock objects into the class you are testing.

public class WebAdaptor {

    public WebAdaptor(Subscriber subscriber) { /* Added a new constructor */
       this.subscriber = subscriber;
    }

    private Subscriber subscriber;

    public void run() {
        subscriber.init();
    }
}

Now you can verify your interactions on the mock, rather than on the real object.

@Test
public void runShouldInvokeSubscriberInit() {

    // Given
    Subscriber mockSubscriber = mock(Subscriber.class);
    WebAdaptor adaptor = new WebAdaptor(mockSubscriber);  // Use the new constructor

    // When
    adaptor.run();

    // Then
    verify(mockSubscriber).init();
}

If adding the Subscriber to the constructor is not the correct approach, you could also consider using a factory to allow WebAdaptor to instantiate new Subscriber objects from a factory which you control. You could then mock the factory to provider mock Subscribers.

They both achieve the same result. Using an annotation (@Mock) is usually considered "cleaner", as you don't fill up your code with boilerplate assignments that all look the same.

Note that in order to use the @Mock annotation, your test class should be annotated with @RunWith(MockitoJUnitRunner.class) or contain a call to MockitoAnnotations.initMocks(this) in its @Before method.

Yes, you are on the right track, putting a mock @Bean in a @Configuration class is one approach, and I'll describe my experience:

The trick is that you need to use a different set of .xml files purely for testing which exclude the live versions of those beans.

@ContextConfiguration(locations = {"context1-test.xml", "context2-test.xml", ...})

And the "-test-xml" files go in src/test/resources.

At least that was my experience in doing the same thing. Maybe there is some way to "override" the beans with the mock versions, but as yet I am not aware of it.

I also chose to put the mocks (I had 5 of them) all together in an own configuration:

@Configuration
public class MockServicesProvider {
     @Bean
     public AnotherBean myMock() { return mock(AnotherBean.class); }
}

Another interesting part of this problem is the common usage of initMocks(this); in the @Before method of your test class.

If the mocks are being used in other places (and they are, that's why you are wiring them up...) then initMocks(this) will blow them away between tests (not literally - just that new mocks will be created and any other mocks wired up in other objects will be "lost").

The solution to this was to call mockito's reset(mockObject) in the @Before method before each test. The same mocks are reset (all the when's and interactions), without creating new mocks.

Note that the Mockito docs for reset say very sternly that this method should not commonly be used, except in the context of mocks being applied via dependency injection, as we are indeed doing in this case :)

Have fun!

I know this thread is old, but it's good to add that since 2014 and this pull request, you can use the @PowerMockRunnerDelegate annotation to "delegate" the run context to SpringJUnit4ClassRunner (or any other runner really).

Above code would look like :

@RunWith(PowerMockRunner.class)
@PowerMockRunnerDelegate(SpringJUnit4ClassRunner.class)
@PrepareForTest(X.class);
public class MyTest {

    // Tests goes here
    ...
}

With this annotation, you don't need the PowerMock rule anymore !

you can mock redisTemplate like this:

@Mock
RedisTemplate<String, String> redisTemplate;

@Mock
private ValueOperations valueOperations;

@Before
public void setUp() {
    MockitoAnnotations.initMocks(this);
    Mockito.when(redisTemplate.opsForValue()).thenReturn(valueOperations);
    Mockito.doNothing().when(valueOperations).set(anyString(), anyString());
}

It seems that deprecated is void verify(VerificationMode mode, Verification verification) while void verify(Verification verification, VerificationMode mode) is still fine so you can just use the verify method like

dummyStatic.verify(
    () -> SomePublicClass.myPublicStaticFunc(anyInt()),
    times(1)
);

I've used the following dependency: testImplementation "org.mockito:mockito-inline:3.12.1".

It seems that with mockito-core you will not be able to mock this because you'll receive

The used MockMaker SubclassByteBuddyMockMaker does not support the creation of static mocks

First of all, you should always mock the direct dependencies of an object, and not its transitive dependencies. So you should mock B, and not C, to test A. Then you would write a unit test for B by mocking C.

Second: you're not injecting the mock anywhere in the unit test. What you should have is:

public class Test {

    // not autowired here
    private A a;

    private B mockB;

    @Test
    public void testA() {
        mockB = mock(B.class);
        when(b.bFn(), anyInt()).thenReturn(something);

        // the missing part: injecting the mock into the tested object
        a = new A(mockB);
        // or a = new A();
        //    a.setB(mockB);

        assertEquals(0, a.aFn());
    }
}

When you use mock(B.class), you get one mock instance of B. That doesn't mean that all the other instances of B will do what the mock does.

Mocking C to test A is a bad practice: unit tests should test one class in isolation of the others. But if you really want that, then create a mock C, create a B and inject the mock C inside it, then create an A and inject the B inside it.

A --> B --> mockC