Example code for blog post: Mocking Static Methods in Android: Let's Wrap it up.

AndroidMockStaticMethod.java

// Example 1 - Test that fails

public class ClassUnderTest {

    public String methodUnderTest(String str)
    {
        if (PhoneNumberUtils.isGlobalPhoneNumber(str))
        {
            return "yes";
        }
        else
        {
            return "no";
        }
    }
}

@RunWith(JUnit4.class)
public class TestThatFails {

    private ClassUnderTest classUnderTest;

    @Before
    public void setup() {
        classUnderTest = new ClassUnderTest();
    }

    @Test
    public void testTheClass() {
        String result = classUnderTest.methodUnderTest("1234");
        assertEquals("yes", result);
    }
}

// Example 2 - Test with wrapper class

public class PhoneNumberUtilsWrapper {

    public boolean isGlobalPhoneNumber(String phoneNumber)
    {
        return PhoneNumberUtils.isGlobalPhoneNumber(phoneNumber);
    }
}

public class ClassUnderTestWithWrapper {

    private PhoneNumberUtilsWrapper wrapper;

    public ClassUnderTestWithWrapper(PhoneNumberUtilsWrapper wrapper) {
        this.wrapper = wrapper;
    }

    public String methodUnderTest(String str)
    {
        if (wrapper.isGlobalPhoneNumber(str))
        {
            return "yes";
        }
        else
        {
            return "no";
        }
    }
}

@RunWith(JUnit4.class)
public class TestWithWrapper {

    @Mock
    PhoneNumberUtilsWrapper wrapper;

    private ClassUnderTestWithWrapper classUnderTest;

    @Before
    public void setup() {
        MockitoAnnotations.initMocks(this);

        classUnderTest = new ClassUnderTestWithWrapper(wrapper);
    }

    @Test
    public void testTheClass() {
        when(wrapper.isGlobalPhoneNumber(anyString())).thenReturn(true);

        String result = classUnderTest.methodUnderTest("1234");
        assertEquals("yes", result);
    }
}

// Example 3 - Test with wrapped method

public class ClassUnderTestWithWrappedMethod {

    public String methodUnderTest(String str)
    {
        if (isGlobalPhoneNumber(str))
        {
            return "yes";
        }
        else
        {
            return "no";
        }
    }

    boolean isGlobalPhoneNumber(String phoneNumber)
    {
        return PhoneNumberUtils.isGlobalPhoneNumber(phoneNumber);
    }
}

@RunWith(JUnit4.class)
public class TestWithWrappedMethod {

    private ClassUnderTestWithWrappedMethod classUnderTest;

    private ClassUnderTestWithWrappedMethod classUnderTestSpy;

    @Before
    public void setup() {
        MockitoAnnotations.initMocks(this);

        classUnderTest = new ClassUnderTestWithWrappedMethod();
        classUnderTestSpy = Mockito.spy(classUnderTest);
    }

    @Test
    public void testTheClass() {
        doReturn(true).when(classUnderTestSpy)
                .isGlobalPhoneNumber(anyString());

        String result = classUnderTestSpy.methodUnderTest("1234");
        assertEquals("yes", result);
    }
}