Module org.junit.platform.commons

Package org.junit.platform.commons.util

Class AnnotationUtils

java.lang.Object

org.junit.platform.commons.util.AnnotationUtils

@API(status=INTERNAL,
     since="1.0")
public final class AnnotationUtils
extends Object

Collection of utilities for working with annotations.

DISCLAIMER

These utilities are intended solely for usage within the JUnit framework itself. Any usage by external parties is not supported. Use at your own risk!

Some utilities are published via the maintained AnnotationSupport class.

Since:

1.0

See Also:

• Annotation
• AnnotatedElement
• AnnotationSupport

Field Summary

Fields

Modifier and Type	Field	Description
private static final ConcurrentHashMap<Class<? extends Annotation>,Boolean>	repeatableAnnotationContainerCache

Constructor Summary

Constructors

Modifier	Constructor	Description
private	AnnotationUtils()

Method Summary

Modifier and Type	Method	Description
static List<Field>	findAnnotatedFields(Class<?> clazz, Class<? extends Annotation> annotationType, Predicate<Field> predicate)
static List<Field>	findAnnotatedFields(Class<?> clazz, Class<? extends Annotation> annotationType, Predicate<Field> predicate, ReflectionUtils.HierarchyTraversalMode traversalMode)	Find all fields of the supplied class or interface that are annotated or meta-annotated with the specified annotationType and match the specified predicate.
static List<Method>	findAnnotatedMethods(Class<?> clazz, Class<? extends Annotation> annotationType, ReflectionUtils.HierarchyTraversalMode traversalMode)
static <A extends Annotation> Optional<A>	findAnnotation(Class<?> clazz, Class<A> annotationType, boolean searchEnclosingClasses)	Find the first annotation of the specified type that is either directly present, meta-present, or indirectly present on the supplied class, optionally searching recursively through the enclosing class hierarchy if not found on the supplied class.
static <A extends Annotation> Optional<A>	findAnnotation(AnnotatedElement element, Class<A> annotationType)
private static <A extends Annotation> Optional<A>	findAnnotation(AnnotatedElement element, Class<A> annotationType, boolean inherited, Set<Annotation> visited)
static <A extends Annotation> Optional<A>	findAnnotation(Parameter parameter, int index, Class<A> annotationType)
static <A extends Annotation> Optional<A>	findAnnotation(Optional<? extends AnnotatedElement> element, Class<A> annotationType)
private static <A extends Annotation> Optional<A>	findMetaAnnotation(Class<A> annotationType, Annotation[] candidates, boolean inherited, Set<Annotation> visited)
static List<Field>	findPublicAnnotatedFields(Class<?> clazz, Class<?> fieldType, Class<? extends Annotation> annotationType)
private static <A extends Annotation> void	findRepeatableAnnotations(Annotation[] candidates, Class<A> annotationType, Class<? extends Annotation> containerType, boolean inherited, Set<A> found, Set<Annotation> visited)
static <A extends Annotation> List<A>	findRepeatableAnnotations(AnnotatedElement element, Class<A> annotationType)
private static <A extends Annotation> void	findRepeatableAnnotations(AnnotatedElement element, Class<A> annotationType, Class<? extends Annotation> containerType, boolean inherited, Set<A> found, Set<Annotation> visited)
static <A extends Annotation> List<A>	findRepeatableAnnotations(Parameter parameter, int index, Class<A> annotationType)
static <A extends Annotation> List<A>	findRepeatableAnnotations(Optional<? extends AnnotatedElement> element, Class<A> annotationType)
private static AnnotatedElement	getEffectiveAnnotatedParameter(Parameter parameter, int index)	Due to a bug in javac on JDK versions prior to JDK 9, looking up annotations directly on a Parameter will fail for inner class constructors.
static boolean	isAnnotated(AnnotatedElement element, Class<? extends Annotation> annotationType)	Determine if an annotation of annotationType is either present or meta-present on the supplied element.
static boolean	isAnnotated(Parameter parameter, int index, Class<? extends Annotation> annotationType)
static boolean	isAnnotated(Optional<? extends AnnotatedElement> element, Class<? extends Annotation> annotationType)	Determine if an annotation of annotationType is either present or meta-present on the supplied optional element.
private static boolean	isInJavaLangAnnotationPackage(Class<? extends Annotation> annotationType)
private static boolean	isRepeatableAnnotationContainer(Class<? extends Annotation> candidateContainerType)	Determine if the supplied annotation type is a container for a repeatable annotation.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

repeatableAnnotationContainerCache

private static final ConcurrentHashMap<Class<? extends Annotation>,Boolean> repeatableAnnotationContainerCache

Constructor Details

AnnotationUtils

private AnnotationUtils()

Method Details

isAnnotated

public static boolean isAnnotated(Optional<? extends AnnotatedElement> element,
 Class<? extends Annotation> annotationType)

Determine if an annotation of annotationType is either present or meta-present on the supplied optional element.

See Also:

• findAnnotation(Optional, Class)
• AnnotationSupport.isAnnotated(Optional, Class)

isAnnotated

public static boolean isAnnotated(Parameter parameter,
 int index,
 Class<? extends Annotation> annotationType)

Since:

1.8

See Also:

• findAnnotation(Parameter, int, Class)

isAnnotated

public static boolean isAnnotated(AnnotatedElement element,
 Class<? extends Annotation> annotationType)

Determine if an annotation of annotationType is either present or meta-present on the supplied element.

Parameters:

element - the element on which to search for the annotation; may be null

annotationType - the annotation type to search for; never null

Returns:

true if the annotation is present or meta-present

See Also:

• findAnnotation(AnnotatedElement, Class)
• AnnotationSupport.isAnnotated(AnnotatedElement, Class)

findAnnotation

public static <A extends Annotation> Optional<A> findAnnotation(Optional<? extends AnnotatedElement> element,
 Class<A> annotationType)

See Also:

• AnnotationSupport.findAnnotation(Optional, Class)

findAnnotation

public static <A extends Annotation> Optional<A> findAnnotation(Parameter parameter,
 int index,
 Class<A> annotationType)

Since:

1.8

See Also:

• findAnnotation(AnnotatedElement, Class)

findAnnotation

public static <A extends Annotation> Optional<A> findAnnotation(AnnotatedElement element,
 Class<A> annotationType)

See Also:

• AnnotationSupport.findAnnotation(AnnotatedElement, Class)

findAnnotation

private static <A extends Annotation> Optional<A> findAnnotation(AnnotatedElement element,
 Class<A> annotationType,
 boolean inherited,
 Set<Annotation> visited)

findMetaAnnotation

private static <A extends Annotation> Optional<A> findMetaAnnotation(Class<A> annotationType,
 Annotation[] candidates,
 boolean inherited,
 Set<Annotation> visited)

findAnnotation

public static <A extends Annotation> Optional<A> findAnnotation(Class<?> clazz,
 Class<A> annotationType,
 boolean searchEnclosingClasses)

Find the first annotation of the specified type that is either directly present, meta-present, or indirectly present on the supplied class, optionally searching recursively through the enclosing class hierarchy if not found on the supplied class.

The enclosing class hierarchy will only be searched above an inner class (i.e., a non-static member class).

Type Parameters:

A - the annotation type

Parameters:

clazz - the class on which to search for the annotation; may be null

annotationType - the annotation type to search for; never null

searchEnclosingClasses - whether the enclosing class hierarchy should be searched

Returns:

an Optional containing the annotation; never null but potentially empty

Since:

1.8

See Also:

• findAnnotation(AnnotatedElement, Class)

findRepeatableAnnotations

public static <A extends Annotation> List<A> findRepeatableAnnotations(Optional<? extends AnnotatedElement> element,
 Class<A> annotationType)

Since:

1.5

See Also:

• AnnotationSupport.findRepeatableAnnotations(Optional, Class)

findRepeatableAnnotations

public static <A extends Annotation> List<A> findRepeatableAnnotations(Parameter parameter,
 int index,
 Class<A> annotationType)

Since:

1.8

See Also:

• findRepeatableAnnotations(AnnotatedElement, Class)

findRepeatableAnnotations

public static <A extends Annotation> List<A> findRepeatableAnnotations(AnnotatedElement element,
 Class<A> annotationType)

See Also:

• AnnotationSupport.findRepeatableAnnotations(AnnotatedElement, Class)

findRepeatableAnnotations

private static <A extends Annotation> void findRepeatableAnnotations(AnnotatedElement element,
 Class<A> annotationType,
 Class<? extends Annotation> containerType,
 boolean inherited,
 Set<A> found,
 Set<Annotation> visited)

findRepeatableAnnotations

private static <A extends Annotation> void findRepeatableAnnotations(Annotation[] candidates,
 Class<A> annotationType,
 Class<? extends Annotation> containerType,
 boolean inherited,
 Set<A> found,
 Set<Annotation> visited)

isRepeatableAnnotationContainer

private static boolean isRepeatableAnnotationContainer(Class<? extends Annotation> candidateContainerType)

Determine if the supplied annotation type is a container for a repeatable annotation.

Since:

1.5

getEffectiveAnnotatedParameter

private static AnnotatedElement getEffectiveAnnotatedParameter(Parameter parameter,
 int index)

Due to a bug in javac on JDK versions prior to JDK 9, looking up annotations directly on a Parameter will fail for inner class constructors.

Bug in javac on JDK versions prior to JDK 9

The parameter annotations array in the compiled byte code for the user's class excludes an entry for the implicit enclosing instance parameter for an inner class constructor.

Workaround

This method provides a workaround for this off-by-one error by helping JUnit maintainers and extension authors to access annotations on the preceding Parameter object (i.e., index - 1). If the supplied index is zero in such situations this method will return null since the parameter for the implicit enclosing instance will never be annotated.

WARNING

The AnnotatedElement returned by this method should never be cast and treated as a Parameter since the metadata (e.g., Parameter.getName(), Parameter.getType(), etc.) will not match those for the declared parameter at the given index in an inner class constructor for code compiled with JDK 8.

Returns:

the supplied Parameter, or the effective Parameter if the aforementioned bug is detected, or null if the bug is detected and the supplied index is 0

Since:

1.8

findPublicAnnotatedFields

public static List<Field> findPublicAnnotatedFields(Class<?> clazz,
 Class<?> fieldType,
 Class<? extends Annotation> annotationType)

See Also:

• AnnotationSupport.findPublicAnnotatedFields(Class, Class, Class)

findAnnotatedFields

public static List<Field> findAnnotatedFields(Class<?> clazz,
 Class<? extends Annotation> annotationType,
 Predicate<Field> predicate)

See Also:

• AnnotationSupport.findAnnotatedFields(Class, Class, Predicate)
• findAnnotatedFields(Class, Class, Predicate, HierarchyTraversalMode)

findAnnotatedFields

public static List<Field> findAnnotatedFields(Class<?> clazz,
 Class<? extends Annotation> annotationType,
 Predicate<Field> predicate,
 ReflectionUtils.HierarchyTraversalMode traversalMode)

Find all fields of the supplied class or interface that are annotated or meta-annotated with the specified annotationType and match the specified predicate.

Parameters:

clazz - the class or interface in which to find the fields; never null

annotationType - the annotation type to search for; never null

predicate - the field filter; never null

traversalMode - the hierarchy traversal mode; never null

Returns:

the list of all such fields found; neither null nor mutable

findAnnotatedMethods

public static List<Method> findAnnotatedMethods(Class<?> clazz,
 Class<? extends Annotation> annotationType,
 ReflectionUtils.HierarchyTraversalMode traversalMode)

See Also:

• AnnotationSupport.findAnnotatedMethods(Class, Class, org.junit.platform.commons.support.HierarchyTraversalMode)

isInJavaLangAnnotationPackage

private static boolean isInJavaLangAnnotationPackage(Class<? extends Annotation> annotationType)