Package org.junit.jupiter.params.provider

Annotation Type MethodSource

  • @Target({ANNOTATION_TYPE,METHOD})
@Retention(RUNTIME)
@Documented
@API(status=EXPERIMENTAL,
     since="5.0")
@ArgumentsSource(org.junit.jupiter.params.provider.MethodArgumentsProvider.class)
public @interface MethodSource
    @MethodSource is an ArgumentsSource which provides access to values returned from factory methods of the class in which this annotation is declared or from static factory methods in external classes referenced by fully qualified method name.

    Each factory method must generate a stream of arguments, and each set of arguments within the stream will be provided as the physical arguments for individual invocations of the annotated @ParameterizedTest method. Generally speaking this translates to a Stream of Arguments (i.e., Stream<Arguments>); however, the actual concrete return type can take on many forms. In this context, a "stream" is anything that JUnit can reliably convert into a Stream, such as Stream, DoubleStream, LongStream, IntStream, Collection, Iterator, Iterable, an array of objects, or an array of primitives. The "arguments" within the stream can be supplied as an instance of Arguments, an array of objects (e.g., Object[]), or a single value if the parameterized test method accepts a single argument.

    Examples

    The following table displays compatible method signatures for parameterized test methods and their corresponding factory methods.

    @ParameterizedTest methodFactory method
    void test(int)static int[] factory()
    void test(int)static IntStream factory()
    void test(String)static String[] factory()
    void test(String)static List<String> factory()
    void test(String)static Stream<String> factory()
    void test(String, int)static Object[][] factory()
    void test(String, int)static Stream<Object[]> factory()
    void test(String, int)static Stream<Arguments> factory()

    Factory methods within the test class must be static unless the PER_CLASS test instance lifecycle mode is used; whereas, factory methods in external classes must always be static. In any case, factory methods must not declare any parameters.

    Since:
    5.0
    See Also:
    Arguments, ArgumentsSource, ParameterizedTest, TestInstance

    • Optional Element Summary

      Optional Elements 
      Modifier and Type Optional Element Description
      String[] value
      The names of factory methods within the test class or in external classes to use as sources for arguments.

    • Element Detail

      • value

        String[] value
        The names of factory methods within the test class or in external classes to use as sources for arguments.

        Factory methods in external classes must be referenced by fully qualified method name — for example, com.example.StringsProviders#blankStrings.

        If no factory method names are declared, a method within the test class that has the same name as the test method will be used as the factory method by default.

        For further information, see the class-level JavaDoc.

        Default:
        {""}