How to use InvocationComparator class of org.mockito.internal.invocation package

To answer your second question first. If you're using JUnit 4, you can annotate your test with

@Test(expected=MyException.class)

to assert that an exception has occured. And to "mock" an exception with mockito, use

when(myMock.doSomething()).thenThrow(new MyException());

Mockito was developed to allow BDD-style unit testing, that is:

• Given (the context in which your unit-test runs)
• When (the events producing the behaviour you're interested in)
• Then (the outcome you're looking for).

as opposed to

• Given
• Expect (here's where the verification gets done)
• When
• Then (go back and look at what you wrote in the Expect because there's no actual info here).

IMHO it produces more readable tests, and allows you to separate things like the context in which you're running (setting up the Mocks) and verification of the behaviour you're interested in. Previous mocking frameworks required you to set up expectations for every interaction, regardless of whether it was relevant to the aspect of behaviour you were looking at in that test or not.

Note that documentToPojo takes a Class as its second argument. any(Foo.class) returns an argument of type Foo, not of type Class<Foo>, whereas eq(WorkItemDTO.class) should return a Class<WorkItemDTO> as expected. I'd do it this way:

when(mongoUtil.documentToPojo(
    Mockito.any(Document.class),
    Mockito.eq(WorkItemDTO.class))).thenReturn(...);

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 must refactor. Extract Runtime.getRuntime().exec() into a separate class:

public class Shell {

  public Process exec(String command) {
    return Runtime.getRuntime().exec(command);
  }

}

Now insted of calling getRuntime() explicitly inject Shell class somehow to your class under test:

public class Foo {

  private final Shell shell;

  public Foo(Shell shell) {
    this.shell = shell;
  }

  //...
  shell.exec(...)

}

In JUnit test simply inject mocked Shell class by passing it to constructor:

@Mock
private Shell shellMock;

new Foo(shellMock);

Sidenote: yes, I am not creating a Shell interface with one implementation. Do you mind? Mockito is not. Bonus: you can now verify if the correct process was called:

verify(shellMock).exec("/usr/bin/gimp");

Try Cntrl + Shift + T on your eclipse screen. Check what are your results. Ideally eclipse should resolve this class only from one dependency. If you are getting multiple results, you may need to add exclusion on certain dependencies.

Also check if you are able to execute your test cases from command prompt. If you are able to do it, then it's not a maven problem. But if something is failing here, check your dependencies.

You can use a mock object to verify that you have called it in the way expected. In Mockito, mocked objects are automatically stubs, and verification occurs explicitly.

From Mockito's "Why do we need another mocking framework?":

 Separation of stubbing and verification. Should let me code in line with intuition: 
 stub before execution, selectively verify interactions afterwards. I don’t 
 want any verification-related code before execution.

You can stub the behavior of calls before they're called. For example (from the Mockito home page):

 when( mockedList.get(0)).thenReturn( "first" );

You can verify interactions with mocked objects after they're called. For example:

 verify( mockedList ).add("one");

There is no public API in Mockito for mock injection. Plus as this annotation is mostly driven on the way things are laid out in a test, it is fairly related to the initialization phase of the test.

Though it might change at some point in the future.

However Mockito annotated fields can be initialized either by the MockitoJUnitRunner or by MockitoAnnotations.initMocks(). They both create mock instances and perform injection.

Also I see in your code that you are using @Autowired - hence spring stuff, probably configured via XML. @InjectMocks wasn't really developed to work with other dependency injection frameworks, as the development was driven by unit test use cases, not integration tests.

You might want to take a look at springockito, which is another project that tries to ease Mockito mock creation in Spring.

Hope that helps

You can check for more properties using one matcher by combining matchers with allOf:

    Matcher<Class> matcherName = allOf(
        hasProperty("propertyName", equalTo(expected1)),
        hasProperty("propertyName2", equalTo(expected2)));

But I guess that what you are actually looking for is the samePropertyValuesAs one, that checks if a bean has the same property values as another one by checking the properties itself instead of the equals method:

    assertThat(yourBean, samePropertyValuesAs(expectedBean));