@Test(expected = BadPracticeException.class)

If you're familiar with JUnit 4 (please be familiar with it) you probably have seen or even used such form of expected exception check @Test(expected = SomeException.class).

Let's see why it is a bad practice.

Initial test

@Test(expected = ValidationFailedException.class)
public void invalidId() {
  User user = new User();
  user.setId(-1);
  user.setName("bla");
  user.validate();
}

// code from AndroidDevSummit Architecture Demo app, sorry Yigit 😅 (please consider making User immutable).

Improved version of the test

@Test
public void validate_shouldThrowIfUserIdIsInvalid() {
  User user = new User();
  user.setId(-1);
  user.setName("bla");

  try {
    user.validate();
    fail();
  } catch (ValidationFailedException expected) {
    assertEquals("invalid user id", expected.getMessage());
  }
}

Now you can clearly see what method is under the test can throw the exception and actually check the reason via checking the exception message.

Improvements

#######1. @Test(expected = ...) -> try-catch.
We're isolating method under the test via precise try-catch on the required method call. This will also protect us from false-positives if setId() or setName() or even constructor will throw ValidationFailedException.

#######2. Explicit fail.
To show our expectations to the readers and to the test runner. You can use even better method failBecauseExceptionWasNotThrown() from AssertJ.

#######3. assertEquals("expected exception message", expected.getMessage())
To check that exception was thrown for a right reason. In our case it could also be an exception from the name validation and initial test won't see the difference!

#######4. Test name invalidId -> validate_shouldThrowIfUserIdIsInvalid.
Such naming is especially helpful if you write and read a lot of tests. methodName_expectedBehavior or something similar is good approach.

Addition: there is an ExpectedException rule right in JUnit, take a look! Thanks to osi from comments.

@Test(expected = ...) is okay for a test containing only one method call and when you definitely know that there is no sense in checking exception message.