BeforeAllCallback defines the API for Extensions that wish to provide additional behavior to test containers once before all tests in the container have been executed.

Concrete implementations often implement AfterAllCallback as well.

Extensions that implement BeforeAllCallback must be registered at the class level.

Constructor Requirements

Consult the documentation in Extension for details on constructor requirements.

Wrapping Behavior

JUnit Jupiter guarantees wrapping behavior for multiple registered extensions that implement lifecycle callbacks such as BeforeAllCallback, AfterAllCallback, BeforeEachCallback, AfterEachCallback, BeforeTestExecutionCallback, and AfterTestExecutionCallback.

That means that, given two extensions Extension1 and Extension2 with Extension1 registered before Extension2, any "before" callbacks implemented by Extension1 are guaranteed to execute before any "before" callbacks implemented by Extension2. Similarly, given the two same two extensions registered in the same order, any "after" callbacks implemented by Extension1 are guaranteed to execute after any "after" callbacks implemented by Extension2. Extension1 is therefore said to wrap Extension2.