What order are the Junit @Before/@After called?

Yes, this behaviour is guaranteed:

@Before:

The @Before methods of superclasses will be run before those of the current class, unless they are overridden in the current class. No other ordering is defined.

@After:

The @After methods declared in superclasses will be run after those of the current class, unless they are overridden in the current class.

One potential gotcha that has bitten me before:

I like to have at most one @Before method in each test class, because order of running the @Before methods defined within a class is not guaranteed. Typically, I will call such a method setUpTest().

But, although @Before is documented as The @Before methods of superclasses will be run before those of the current class. No other ordering is defined., this only applies if each method marked with @Before has a unique name in the class hierarchy.

For example, I had the following:

public class AbstractFooTest {
  @Before
  public void setUpTest() { 
     ... 
  }
}

public void FooTest extends AbstractFooTest {
  @Before
  public void setUpTest() { 
    ...
  }
}

I expected AbstractFooTest.setUpTest() to run before FooTest.setUpTest(), but only FooTest.setupTest() was executed. AbstractFooTest.setUpTest() was not called at all.

The code must be modified as follows to work:

public void FooTest extends AbstractFooTest {
  @Before
  public void setUpTest() {
    super.setUpTest();
    ...
  }
}