如何在TestSuite界面中使用junit @Beforeclass && @Afterclass？

Question

Problem: I have a custom Interface for a TestSuite .

public interface TestSuite {

  abstract void setupRestAssuredForSuite();
  abstract void restoreDatabase();
  abstract void executeSuitePreparation();
  abstract void executeSuiteTearDown();

}

How can I have my interface contain @BeforeClass and @AfterClass annotations from junit and my implementations of the TestSuite interface to acknowledge those? Should I be doing this another way completely? I am curious to know if such a thing is possible with interfaces.

do I need to write the annotations manually in every class which implements TestSuite? or can I have the executeSuitePreparation(); and executeSuiteTearDown(); methods running without the annotations because they somehow exist in TestSuite itself and I just need to implement the code behind setup/teardown.

public class Foo extends Bar implements TestSuite

To my knowledge the @Beforeclass and @Afterclass methods must be static.

Is this a silly way of approaching the situation? Could you recommend a different way of doing it if that is the case.

Answer 1

You're trying to use interfaces as mixins. Interfaces are not mixins.

Probably the best you can do is to write static methods in your interface that do the required setup:

public interface TestSuite {

  abstract void setupRestAssuredForSuite();
  ...


  static SomeReturn setup()
  {
      Database database = new Database();
      ...
      return database;
  }

  static void teardown(SomeType foo)
  {
      foo.reset();
  }
}

Then in your concrete implementations you can do:

public class Foo extends Bar implements TestSuite
{
    private static Foo foo;

    @BeforeClass
    public void beforeClass()
    {
        foo = TestSuite.setup();
    }

    @BeforeClass
    public void beforeClass()
    {
        TestSuite.teardown(foo);
    }
}

I would strongly encourage you to re-think whether you need to use inheritance in your tests. It seems like a code smell to me, and indicates that your tests are perhaps not focused enough.