JUnit 4 base functionality

Question

What is the proper way with JUnit 4 to create test cases to use common functionality: e.g. setup that is common to several unit test classes? What I did was create a test case and put the common functionality in the @Before method, then any test case that needs this would extend the base class. However, this seems to require doing: super.setUp() in every subclass.

Is there a better way?

EDIT

Actually my proposed solution is not working. Sometimes JUnit will call the base class TWICE. Once if it happens to run the test on the base class first, and again when it reaches a child class (at least I think this is whats happening). So a better way of "inheriting" common test case functionality would be great.

Answer 1

You don't need to invoker super.setup() if you use the @Before annotation:

When writing tests, it is common to find that several tests need similar objects created before they can run. Annotating a public void method with @Before causes that method to be run before the Test method. The @Before methods of superclasses will be run before those of the current class.

I'd suggest something like this:

  @Before
  public void initForAll() {}

In the super/Main class

and any

  @Before
  public void initTest() {...}

In your Testcases.

EDIT:

To answer your questions in the edit.

1. You could use @BeforeClass which will be invoked once per TestClass.
2. But I Think you are looking for something like a lazy /static Initialisation.

I do this like this:

private boolean initialized = false;

@BeforeClass
public static void init()
{
  if(initialized)
  {
    return;
  }

  //Initialize everything

  initialized = true;
}