1. Generation_P Consulting Ltd
Software Solutions for the Travel Industry
TDD
Make your life better
Antanina Shafranskaya
Antanina.Shafranskaya@generation_p.com

2. TDD: way to better life
Test before code!
TDD principals:
think first

trivial first

test <=> what ; implementation <=> how

different levels of tests

red – green – refactor
red: behavior (responsibility oriented design)

green: coding

refactor: design, refactor


3. TDD: Pair programming
ping – pong

who has keyboard is a King!

through-test driving


4. TDD: Testing best practices

5. TDD: Test naming

6. TDD: Test naming

7. TDD: Exception processing

8. TDD: given-when-then

9. TDD: multiple asserts

10. TDD: Whole test system
manual
auto gui
acceptance
integration
unit tests

11. TDD: Unit tests
One test – one behavior

Independent: isolated class

Reliable

Fast


12. TDD: Integration and Acceptance Tests
integration: component

communication with some
isolation
acceptance: full system test, no

isolation or mocks
client requirements


13. TDD: Mocks
fake – some little implementation

stub – return some predefined result

mock – object with programmed expectation

spy – stub with flow verification


14. TDD: Mockito
Easy to:
stub methods

verify behavior

verify sequence of calls

Cannot:
mock final classes,

methods
mock static


15. TDD: Mockito
 @RunWith(MockitoJUnitRunner.class) annotation at
the class-level of the test case
 @Mock annotation at mocking objects
 init tested class in method annotated with @Before
 when(mock.methodCall()).thenReturn(someResult);
 doThrow(exception).when(object).voidMethodCall();
 verify(mock, times).methodCall()
 verifyZeroInteractions(mocks)
 inOrder(mock)

16. TDD: Mockito

17. TDD: PowerMock
Easy way to mock:
static methods

final methods or classes

private methods

construction of new objects

partial mocking


18. TDD: PowerMock
 @RunWith(PowerMockRunner.class) annotation at the class-level of the test case.
 @PrepareForTest(ClassThatContainsStaticMethod.class) annotation at the class-level
of the test case.
 PowerMock.mockStatic(ClassThatContainsStaticMethod.class) to mock all methods of
this class.
 PowerMock.mockStaticPartial(ClassThatContainsStaticMethod.class, "methodName",
ArgumentClass.class);
 PowerMock.replay(ClassThatContainsStaticMethod.class) to change the class to
replay mode.
 PowerMock.verify(ClassThatContainsStaticMethod.class) to change the class to verify
mode.
example: http://code.google.com/p/powermock/source/browse/trunk/modules/module-
test/easymock/junit4-
test/src/test/java/samples/junit4/singleton/MockStaticTest.java

19. What to read?
Robert C. Martin “Clean Code: A Handbook

of Agile Software Craftsmanship”
Joshua Kerievsky “Refactoring to Patterns”

Steve Freeman, Nat Pryce “Growing Object-

Oriented Software, Guided by Tests”

20. Questions?
Thank you and good luck!

21. References
 http://www.slideshare.net/agileee/clean-
tests
 http://www.slideshare.net/wakaleo/junit-
kung-fu-getting-more-out-of-your-unit-
tests
 http://mockito.googlecode.com/svn/tags/
latest/javadoc/org/mockito/Mockito.html
 http://code.google.com/p/powermock/