Java unit test factory
Annotation Type TestFactory
@Target(ANNOTATION_TYPE,METHOD>) @Retention(RUNTIME) @Documented @API(status=MAINTAINED, since="5.3") @Testable public @interface TestFactory @TestFactory is used to signal that the annotated method is a test factory method. In contrast to @Test methods, a test factory is not itself a test case but rather a factory for test cases. @TestFactory methods must not be private or static and must return a Stream , Collection , Iterable , Iterator , or array of DynamicNode instances. Supported subclasses of DynamicNode include DynamicContainer and DynamicTest . Dynamic tests will be executed lazily, enabling dynamic and even non-deterministic generation of test cases. Any Stream returned by a @TestFactory will be properly closed by calling stream.close() , making it safe to use a resource such as Files.lines() as the initial source of the stream. @TestFactory methods may optionally declare parameters to be resolved by ParameterResolvers .
Test Execution Order
By default, test methods will be ordered using an algorithm that is deterministic but intentionally nonobvious. This ensures that subsequent runs of a test suite execute test methods in the same order, thereby allowing for repeatable builds. In this context, a test method is any instance method that is directly annotated or meta-annotated with @Test , @RepeatedTest , @ParameterizedTest , @TestFactory , or @TestTemplate . Although true unit tests typically should not rely on the order in which they are executed, there are times when it is necessary to enforce a specific test method execution order — for example, when writing integration tests or functional tests where the sequence of the tests is important, especially in conjunction with @TestInstance(Lifecycle.PER_CLASS) . To control the order in which test methods are executed, annotate your test class or test interface with @TestMethodOrder and specify the desired MethodOrderer implementation.