Package org.springframework.core.annotation

Class AnnotatedElementUtils

java.lang.Object

org.springframework.core.annotation.AnnotatedElementUtils

public abstract class AnnotatedElementUtils
extends Object

General utility methods for finding annotations, meta-annotations, and repeatable annotations on AnnotatedElements.

AnnotatedElementUtils defines the public API for Spring's meta-annotation programming model with support for annotation attribute overrides. If you do not need support for annotation attribute overrides, consider using AnnotationUtils instead.

Note that the features of this class are not provided by the JDK's introspection facilities themselves.

Annotation Attribute Overrides

Support for meta-annotations with attribute overrides in composed annotations is provided by all variants of the getMergedAnnotationAttributes(), getMergedAnnotation(), getAllMergedAnnotations(), getMergedRepeatableAnnotations(), findMergedAnnotationAttributes(), findMergedAnnotation(), findAllMergedAnnotations(), and findMergedRepeatableAnnotations() methods.

Find vs. Get Semantics

The search algorithms used by methods in this class follow either find or get semantics. Consult the javadocs for each individual method for details on which search algorithm is used.

Get semantics are limited to searching for annotations that are either present on an AnnotatedElement (i.e. declared locally or inherited) or declared within the annotation hierarchy above the AnnotatedElement.

Find semantics are much more exhaustive, providing get semantics plus support for the following:

• Searching on interfaces, if the annotated element is a class
• Searching on superclasses, if the annotated element is a class
• Resolving bridged methods, if the annotated element is a method
• Searching on methods in interfaces, if the annotated element is a method
• Searching on methods in superclasses, if the annotated element is a method

Support for @Inherited

Methods following get semantics will honor the contract of Java's @Inherited annotation except that locally declared annotations (including custom composed annotations) will be favored over inherited annotations. In contrast, methods following find semantics will completely ignore the presence of @Inherited since the find search algorithm manually traverses type and method hierarchies and thereby implicitly supports annotation inheritance without a need for @Inherited.

Since:

4.0

Author:

Phillip Webb, Juergen Hoeller, Sam Brannen

See Also:

• AliasFor
• AnnotationAttributes
• AnnotationUtils
• BridgeMethodResolver

Constructor Summary

Constructors

Constructor	Description
AnnotatedElementUtils()

Method Summary

Modifier and Type	Method	Description
static <A extends Annotation> Set<A>	findAllMergedAnnotations(AnnotatedElement element, Class<A> annotationType)	Find all annotations of the specified annotationType within the annotation hierarchy above the supplied element; and for each annotation found, merge that annotation's attributes with matching attributes from annotations in lower levels of the annotation hierarchy and synthesize the results back into an annotation of the specified annotationType.
static Set<Annotation>	findAllMergedAnnotations(AnnotatedElement element, Set<Class<? extends Annotation>> annotationTypes)	Find all annotations of the specified annotationTypes within the annotation hierarchy above the supplied element; and for each annotation found, merge that annotation's attributes with matching attributes from annotations in lower levels of the annotation hierarchy and synthesize the results back into an annotation of the corresponding annotationType.
static <A extends Annotation> A	findMergedAnnotation(AnnotatedElement element, Class<A> annotationType)	Find the first annotation of the specified annotationType within the annotation hierarchy above the supplied element, merge that annotation's attributes with matching attributes from annotations in lower levels of the annotation hierarchy, and synthesize the result back into an annotation of the specified annotationType.
static AnnotationAttributes	findMergedAnnotationAttributes(AnnotatedElement element, Class<? extends Annotation> annotationType, boolean classValuesAsString, boolean nestedAnnotationsAsMap)	Find the first annotation of the specified annotationType within the annotation hierarchy above the supplied element and merge that annotation's attributes with matching attributes from annotations in lower levels of the annotation hierarchy.
static AnnotationAttributes	findMergedAnnotationAttributes(AnnotatedElement element, String annotationName, boolean classValuesAsString, boolean nestedAnnotationsAsMap)	Find the first annotation of the specified annotationName within the annotation hierarchy above the supplied element and merge that annotation's attributes with matching attributes from annotations in lower levels of the annotation hierarchy.
static <A extends Annotation> Set<A>	findMergedRepeatableAnnotations(AnnotatedElement element, Class<A> annotationType)	Find all repeatable annotations of the specified annotationType within the annotation hierarchy above the supplied element; and for each annotation found, merge that annotation's attributes with matching attributes from annotations in lower levels of the annotation hierarchy and synthesize the results back into an annotation of the specified annotationType.
static <A extends Annotation> Set<A>	findMergedRepeatableAnnotations(AnnotatedElement element, Class<A> annotationType, Class<? extends Annotation> containerType)	Find all repeatable annotations of the specified annotationType within the annotation hierarchy above the supplied element; and for each annotation found, merge that annotation's attributes with matching attributes from annotations in lower levels of the annotation hierarchy and synthesize the results back into an annotation of the specified annotationType.
static AnnotatedElement	forAnnotations(Annotation... annotations)	Build an adapted AnnotatedElement for the given annotations, typically for use with other methods on AnnotatedElementUtils.
static MultiValueMap<String,Object>	getAllAnnotationAttributes(AnnotatedElement element, String annotationName)	Get the annotation attributes of all annotations of the specified annotationName in the annotation hierarchy above the supplied AnnotatedElement and store the results in a MultiValueMap.
static MultiValueMap<String,Object>	getAllAnnotationAttributes(AnnotatedElement element, String annotationName, boolean classValuesAsString, boolean nestedAnnotationsAsMap)	Get the annotation attributes of all annotations of the specified annotationName in the annotation hierarchy above the supplied AnnotatedElement and store the results in a MultiValueMap.
static <A extends Annotation> Set<A>	getAllMergedAnnotations(AnnotatedElement element, Class<A> annotationType)	Get all annotations of the specified annotationType within the annotation hierarchy above the supplied element; and for each annotation found, merge that annotation's attributes with matching attributes from annotations in lower levels of the annotation hierarchy and synthesize the results back into an annotation of the specified annotationType.
static Set<Annotation>	getAllMergedAnnotations(AnnotatedElement element, Set<Class<? extends Annotation>> annotationTypes)	Get all annotations of the specified annotationTypes within the annotation hierarchy above the supplied element; and for each annotation found, merge that annotation's attributes with matching attributes from annotations in lower levels of the annotation hierarchy and synthesize the results back into an annotation of the corresponding annotationType.
static <A extends Annotation> A	getMergedAnnotation(AnnotatedElement element, Class<A> annotationType)	Get the first annotation of the specified annotationType within the annotation hierarchy above the supplied element, merge that annotation's attributes with matching attributes from annotations in lower levels of the annotation hierarchy, and synthesize the result back into an annotation of the specified annotationType.
static AnnotationAttributes	getMergedAnnotationAttributes(AnnotatedElement element, Class<? extends Annotation> annotationType)	Get the first annotation of the specified annotationType within the annotation hierarchy above the supplied element and merge that annotation's attributes with matching attributes from annotations in lower levels of the annotation hierarchy.
static AnnotationAttributes	getMergedAnnotationAttributes(AnnotatedElement element, String annotationName)	Get the first annotation of the specified annotationName within the annotation hierarchy above the supplied element and merge that annotation's attributes with matching attributes from annotations in lower levels of the annotation hierarchy.
static AnnotationAttributes	getMergedAnnotationAttributes(AnnotatedElement element, String annotationName, boolean classValuesAsString, boolean nestedAnnotationsAsMap)	Get the first annotation of the specified annotationName within the annotation hierarchy above the supplied element and merge that annotation's attributes with matching attributes from annotations in lower levels of the annotation hierarchy.
static <A extends Annotation> Set<A>	getMergedRepeatableAnnotations(AnnotatedElement element, Class<A> annotationType)	Get all repeatable annotations of the specified annotationType within the annotation hierarchy above the supplied element; and for each annotation found, merge that annotation's attributes with matching attributes from annotations in lower levels of the annotation hierarchy and synthesize the results back into an annotation of the specified annotationType.
static <A extends Annotation> Set<A>	getMergedRepeatableAnnotations(AnnotatedElement element, Class<A> annotationType, Class<? extends Annotation> containerType)	Get all repeatable annotations of the specified annotationType within the annotation hierarchy above the supplied element; and for each annotation found, merge that annotation's attributes with matching attributes from annotations in lower levels of the annotation hierarchy and synthesize the results back into an annotation of the specified annotationType.
static Set<String>	getMetaAnnotationTypes(AnnotatedElement element, Class<? extends Annotation> annotationType)	Get the fully qualified class names of all meta-annotation types present on the annotation (of the specified annotationType) on the supplied AnnotatedElement.
static Set<String>	getMetaAnnotationTypes(AnnotatedElement element, String annotationName)	Get the fully qualified class names of all meta-annotation types present on the annotation (of the specified annotationName) on the supplied AnnotatedElement.
static boolean	hasAnnotation(AnnotatedElement element, Class<? extends Annotation> annotationType)	Determine if an annotation of the specified annotationType is available on the supplied AnnotatedElement or within the annotation hierarchy above the specified element.
static boolean	hasMetaAnnotationTypes(AnnotatedElement element, Class<? extends Annotation> annotationType)	Determine if the supplied AnnotatedElement is annotated with a composed annotation that is meta-annotated with an annotation of the specified annotationType.
static boolean	hasMetaAnnotationTypes(AnnotatedElement element, String annotationName)	Determine if the supplied AnnotatedElement is annotated with a composed annotation that is meta-annotated with an annotation of the specified annotationName.
static boolean	isAnnotated(AnnotatedElement element, Class<? extends Annotation> annotationType)	Determine if an annotation of the specified annotationType is present on the supplied AnnotatedElement or within the annotation hierarchy above the specified element.
static boolean	isAnnotated(AnnotatedElement element, String annotationName)	Determine if an annotation of the specified annotationName is present on the supplied AnnotatedElement or within the annotation hierarchy above the specified element.

Methods inherited from class java.lang.Object

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

Constructor Details

AnnotatedElementUtils

public AnnotatedElementUtils()

Method Details

forAnnotations

public static AnnotatedElement forAnnotations(Annotation... annotations)

Build an adapted AnnotatedElement for the given annotations, typically for use with other methods on AnnotatedElementUtils.

Parameters:

annotations - the annotations to expose through the AnnotatedElement

Since:

4.3

getMetaAnnotationTypes

public static Set<String> getMetaAnnotationTypes(AnnotatedElement element,
 Class<? extends Annotation> annotationType)

Get the fully qualified class names of all meta-annotation types present on the annotation (of the specified annotationType) on the supplied AnnotatedElement.

This method follows get semantics as described in the class-level javadoc.

Parameters:

element - the annotated element

annotationType - the annotation type on which to find meta-annotations

Returns:

the names of all meta-annotations present on the annotation, or an empty set if not found

Since:

4.2

See Also:

• getMetaAnnotationTypes(AnnotatedElement, String)
• hasMetaAnnotationTypes(java.lang.reflect.AnnotatedElement, java.lang.Class<? extends java.lang.annotation.Annotation>)

getMetaAnnotationTypes

public static Set<String> getMetaAnnotationTypes(AnnotatedElement element,
 String annotationName)

Get the fully qualified class names of all meta-annotation types present on the annotation (of the specified annotationName) on the supplied AnnotatedElement.

This method follows get semantics as described in the class-level javadoc.

Parameters:

element - the annotated element

annotationName - the fully qualified class name of the annotation type on which to find meta-annotations

Returns:

the names of all meta-annotations present on the annotation, or an empty set if none found

See Also:

• getMetaAnnotationTypes(AnnotatedElement, Class)
• hasMetaAnnotationTypes(java.lang.reflect.AnnotatedElement, java.lang.Class<? extends java.lang.annotation.Annotation>)

hasMetaAnnotationTypes

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

Determine if the supplied AnnotatedElement is annotated with a composed annotation that is meta-annotated with an annotation of the specified annotationType.

This method follows get semantics as described in the class-level javadoc.

Parameters:

element - the annotated element

annotationType - the meta-annotation type to find

Returns:

true if a matching meta-annotation is present

Since:

4.2.3

See Also:

• getMetaAnnotationTypes(java.lang.reflect.AnnotatedElement, java.lang.Class<? extends java.lang.annotation.Annotation>)

hasMetaAnnotationTypes

public static boolean hasMetaAnnotationTypes(AnnotatedElement element,
 String annotationName)

Determine if the supplied AnnotatedElement is annotated with a composed annotation that is meta-annotated with an annotation of the specified annotationName.

This method follows get semantics as described in the class-level javadoc.

Parameters:

element - the annotated element

annotationName - the fully qualified class name of the meta-annotation type to find

Returns:

true if a matching meta-annotation is present

See Also:

• getMetaAnnotationTypes(java.lang.reflect.AnnotatedElement, java.lang.Class<? extends java.lang.annotation.Annotation>)

isAnnotated

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

Determine if an annotation of the specified annotationType is present on the supplied AnnotatedElement or within the annotation hierarchy above the specified element.

If this method returns true, then getMergedAnnotationAttributes(java.lang.reflect.AnnotatedElement, java.lang.Class<? extends java.lang.annotation.Annotation>) will return a non-null value.

This method follows get semantics as described in the class-level javadoc.

Parameters:

element - the annotated element

annotationType - the annotation type to find

Returns:

true if a matching annotation is present

Since:

4.2.3

See Also:

• hasAnnotation(AnnotatedElement, Class)

isAnnotated

public static boolean isAnnotated(AnnotatedElement element,
 String annotationName)

Determine if an annotation of the specified annotationName is present on the supplied AnnotatedElement or within the annotation hierarchy above the specified element.

If this method returns true, then getMergedAnnotationAttributes(java.lang.reflect.AnnotatedElement, java.lang.Class<? extends java.lang.annotation.Annotation>) will return a non-null value.

This method follows get semantics as described in the class-level javadoc.

Parameters:

element - the annotated element

annotationName - the fully qualified class name of the annotation type to find

Returns:

true if a matching annotation is present

getMergedAnnotationAttributes

@Nullable
public static AnnotationAttributes getMergedAnnotationAttributes(AnnotatedElement element,
 Class<? extends Annotation> annotationType)

Get the first annotation of the specified annotationType within the annotation hierarchy above the supplied element and merge that annotation's attributes with matching attributes from annotations in lower levels of the annotation hierarchy.

@AliasFor semantics are fully supported, both within a single annotation and within the annotation hierarchy.

This method delegates to getMergedAnnotationAttributes(AnnotatedElement, String).

Parameters:

element - the annotated element

annotationType - the annotation type to find

Returns:

the merged AnnotationAttributes, or null if not found

Since:

4.2

See Also:

• getMergedAnnotationAttributes(AnnotatedElement, String, boolean, boolean)
• findMergedAnnotationAttributes(AnnotatedElement, String, boolean, boolean)
• getMergedAnnotation(AnnotatedElement, Class)
• findMergedAnnotation(AnnotatedElement, Class)

getMergedAnnotationAttributes

@Nullable
public static AnnotationAttributes getMergedAnnotationAttributes(AnnotatedElement element,
 String annotationName)

Get the first annotation of the specified annotationName within the annotation hierarchy above the supplied element and merge that annotation's attributes with matching attributes from annotations in lower levels of the annotation hierarchy.

@AliasFor semantics are fully supported, both within a single annotation and within the annotation hierarchy.

This method delegates to getMergedAnnotationAttributes(AnnotatedElement, String, boolean, boolean), supplying false for classValuesAsString and nestedAnnotationsAsMap.

Parameters:

element - the annotated element

annotationName - the fully qualified class name of the annotation type to find

Returns:

the merged AnnotationAttributes, or null if not found

Since:

4.2

See Also:

• getMergedAnnotationAttributes(AnnotatedElement, String, boolean, boolean)
• findMergedAnnotationAttributes(AnnotatedElement, String, boolean, boolean)
• findMergedAnnotation(AnnotatedElement, Class)
• getAllAnnotationAttributes(AnnotatedElement, String)

getMergedAnnotationAttributes

@Nullable
public static AnnotationAttributes getMergedAnnotationAttributes(AnnotatedElement element,
 String annotationName,
 boolean classValuesAsString,
 boolean nestedAnnotationsAsMap)

Get the first annotation of the specified annotationName within the annotation hierarchy above the supplied element and merge that annotation's attributes with matching attributes from annotations in lower levels of the annotation hierarchy.

Attributes from lower levels in the annotation hierarchy override attributes of the same name from higher levels, and @AliasFor semantics are fully supported, both within a single annotation and within the annotation hierarchy.

In contrast to getAllAnnotationAttributes(java.lang.reflect.AnnotatedElement, java.lang.String), the search algorithm used by this method will stop searching the annotation hierarchy once the first annotation of the specified annotationName has been found. As a consequence, additional annotations of the specified annotationName will be ignored.

This method follows get semantics as described in the class-level javadoc.

Parameters:

element - the annotated element

annotationName - the fully qualified class name of the annotation type to find

classValuesAsString - whether to convert Class references into Strings or to preserve them as Class references

nestedAnnotationsAsMap - whether to convert nested Annotation instances into AnnotationAttributes maps or to preserve them as Annotation instances

Returns:

the merged AnnotationAttributes, or null if not found

Since:

4.2

See Also:

• findMergedAnnotation(AnnotatedElement, Class)
• findMergedAnnotationAttributes(AnnotatedElement, String, boolean, boolean)
• getAllAnnotationAttributes(AnnotatedElement, String, boolean, boolean)

getMergedAnnotation

@Nullable
public static <A extends Annotation> A getMergedAnnotation(AnnotatedElement element,
 Class<A> annotationType)

Get the first annotation of the specified annotationType within the annotation hierarchy above the supplied element, merge that annotation's attributes with matching attributes from annotations in lower levels of the annotation hierarchy, and synthesize the result back into an annotation of the specified annotationType.

@AliasFor semantics are fully supported, both within a single annotation and within the annotation hierarchy.

Parameters:

element - the annotated element

annotationType - the annotation type to find

Returns:

the merged, synthesized Annotation, or null if not found

Since:

4.2

See Also:

• findMergedAnnotation(AnnotatedElement, Class)

getAllMergedAnnotations

public static <A extends Annotation> Set<A> getAllMergedAnnotations(AnnotatedElement element,
 Class<A> annotationType)

Get all annotations of the specified annotationType within the annotation hierarchy above the supplied element; and for each annotation found, merge that annotation's attributes with matching attributes from annotations in lower levels of the annotation hierarchy and synthesize the results back into an annotation of the specified annotationType.

@AliasFor semantics are fully supported, both within a single annotation and within annotation hierarchies.

This method follows get semantics as described in the class-level javadoc.

Parameters:

element - the annotated element (never null)

annotationType - the annotation type to find (never null)

Returns:

the set of all merged, synthesized Annotations found, or an empty set if none were found

Since:

4.3

See Also:

• getMergedAnnotation(AnnotatedElement, Class)
• getAllAnnotationAttributes(AnnotatedElement, String)
• findAllMergedAnnotations(AnnotatedElement, Class)

getAllMergedAnnotations

public static Set<Annotation> getAllMergedAnnotations(AnnotatedElement element,
 Set<Class<? extends Annotation>> annotationTypes)

Get all annotations of the specified annotationTypes within the annotation hierarchy above the supplied element; and for each annotation found, merge that annotation's attributes with matching attributes from annotations in lower levels of the annotation hierarchy and synthesize the results back into an annotation of the corresponding annotationType.

@AliasFor semantics are fully supported, both within a single annotation and within annotation hierarchies.

This method follows get semantics as described in the class-level javadoc.

Parameters:

element - the annotated element (never null)

annotationTypes - the annotation types to find

Returns:

the set of all merged, synthesized Annotations found, or an empty set if none were found

Since:

5.1

See Also:

• getAllMergedAnnotations(AnnotatedElement, Class)

getMergedRepeatableAnnotations

public static <A extends Annotation> Set<A> getMergedRepeatableAnnotations(AnnotatedElement element,
 Class<A> annotationType)

Get all repeatable annotations of the specified annotationType within the annotation hierarchy above the supplied element; and for each annotation found, merge that annotation's attributes with matching attributes from annotations in lower levels of the annotation hierarchy and synthesize the results back into an annotation of the specified annotationType.

The container type that holds the repeatable annotations will be looked up via Repeatable.

@AliasFor semantics are fully supported, both within a single annotation and within annotation hierarchies.

This method follows get semantics as described in the class-level javadoc.

Parameters:

element - the annotated element (never null)

annotationType - the annotation type to find (never null)

Returns:

the set of all merged repeatable Annotations found, or an empty set if none were found

Throws:

IllegalArgumentException - if the element or annotationType is null, or if the container type cannot be resolved

Since:

4.3

See Also:

• getMergedAnnotation(AnnotatedElement, Class)
• getAllMergedAnnotations(AnnotatedElement, Class)
• getMergedRepeatableAnnotations(AnnotatedElement, Class, Class)

getMergedRepeatableAnnotations

public static <A extends Annotation> Set<A> getMergedRepeatableAnnotations(AnnotatedElement element,
 Class<A> annotationType,
 @Nullable
 Class<? extends Annotation> containerType)

Get all repeatable annotations of the specified annotationType within the annotation hierarchy above the supplied element; and for each annotation found, merge that annotation's attributes with matching attributes from annotations in lower levels of the annotation hierarchy and synthesize the results back into an annotation of the specified annotationType.

@AliasFor semantics are fully supported, both within a single annotation and within annotation hierarchies.

This method follows get semantics as described in the class-level javadoc.

WARNING: if the supplied containerType is not null, the search will be restricted to supporting only repeatable annotations whose container is the supplied containerType. This prevents the search from finding repeatable annotations declared as meta-annotations on other types of repeatable annotations. If you need to support such a use case, favor getMergedRepeatableAnnotations(AnnotatedElement, Class) over this method or alternatively use the MergedAnnotations API directly in conjunction with RepeatableContainers that are composed to support multiple repeatable annotation types.

Parameters:

element - the annotated element (never null)

annotationType - the annotation type to find (never null)

containerType - the type of the container that holds the annotations; may be null if the container type should be looked up via Repeatable

Returns:

the set of all merged repeatable Annotations found, or an empty set if none were found

Throws:

IllegalArgumentException - if the element or annotationType is null, or if the container type cannot be resolved

AnnotationConfigurationException - if the supplied containerType is not a valid container annotation for the supplied annotationType

Since:

4.3

See Also:

• getMergedAnnotation(AnnotatedElement, Class)
• getAllMergedAnnotations(AnnotatedElement, Class)

getAllAnnotationAttributes

@Nullable
public static MultiValueMap<String,Object> getAllAnnotationAttributes(AnnotatedElement element,
 String annotationName)

Get the annotation attributes of all annotations of the specified annotationName in the annotation hierarchy above the supplied AnnotatedElement and store the results in a MultiValueMap.

Note: in contrast to getMergedAnnotationAttributes(AnnotatedElement, String), this method does not support attribute overrides.

This method follows get semantics as described in the class-level javadoc.

Parameters:

element - the annotated element

annotationName - the fully qualified class name of the annotation type to find

Returns:

a MultiValueMap keyed by attribute name, containing the annotation attributes from all annotations found, or null if not found

See Also:

• getAllAnnotationAttributes(AnnotatedElement, String, boolean, boolean)

getAllAnnotationAttributes

@Nullable
public static MultiValueMap<String,Object> getAllAnnotationAttributes(AnnotatedElement element,
 String annotationName,
 boolean classValuesAsString,
 boolean nestedAnnotationsAsMap)

Get the annotation attributes of all annotations of the specified annotationName in the annotation hierarchy above the supplied AnnotatedElement and store the results in a MultiValueMap.

Note: in contrast to getMergedAnnotationAttributes(AnnotatedElement, String), this method does not support attribute overrides.

This method follows get semantics as described in the class-level javadoc.

Parameters:

element - the annotated element

annotationName - the fully qualified class name of the annotation type to find

classValuesAsString - whether to convert Class references into Strings or to preserve them as Class references

nestedAnnotationsAsMap - whether to convert nested Annotation instances into AnnotationAttributes maps or to preserve them as Annotation instances

Returns:

a MultiValueMap keyed by attribute name, containing the annotation attributes from all annotations found, or null if not found

hasAnnotation

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

Determine if an annotation of the specified annotationType is available on the supplied AnnotatedElement or within the annotation hierarchy above the specified element.

If this method returns true, then findMergedAnnotationAttributes(java.lang.reflect.AnnotatedElement, java.lang.Class<? extends java.lang.annotation.Annotation>, boolean, boolean) will return a non-null value.

This method follows find semantics as described in the class-level javadoc.

Parameters:

element - the annotated element

annotationType - the annotation type to find

Returns:

true if a matching annotation is present

Since:

4.3

See Also:

• isAnnotated(AnnotatedElement, Class)

findMergedAnnotationAttributes

@Nullable
public static AnnotationAttributes findMergedAnnotationAttributes(AnnotatedElement element,
 Class<? extends Annotation> annotationType,
 boolean classValuesAsString,
 boolean nestedAnnotationsAsMap)

Find the first annotation of the specified annotationType within the annotation hierarchy above the supplied element and merge that annotation's attributes with matching attributes from annotations in lower levels of the annotation hierarchy.

Attributes from lower levels in the annotation hierarchy override attributes of the same name from higher levels, and @AliasFor semantics are fully supported, both within a single annotation and within the annotation hierarchy.

In contrast to getAllAnnotationAttributes(java.lang.reflect.AnnotatedElement, java.lang.String), the search algorithm used by this method will stop searching the annotation hierarchy once the first annotation of the specified annotationType has been found. As a consequence, additional annotations of the specified annotationType will be ignored.

This method follows find semantics as described in the class-level javadoc.

Parameters:

element - the annotated element

annotationType - the annotation type to find

classValuesAsString - whether to convert Class references into Strings or to preserve them as Class references

nestedAnnotationsAsMap - whether to convert nested Annotation instances into AnnotationAttributes maps or to preserve them as Annotation instances

Returns:

the merged AnnotationAttributes, or null if not found

Since:

4.2

See Also:

• findMergedAnnotation(AnnotatedElement, Class)
• getMergedAnnotationAttributes(AnnotatedElement, String, boolean, boolean)

findMergedAnnotationAttributes

@Nullable
public static AnnotationAttributes findMergedAnnotationAttributes(AnnotatedElement element,
 String annotationName,
 boolean classValuesAsString,
 boolean nestedAnnotationsAsMap)

Find the first annotation of the specified annotationName within the annotation hierarchy above the supplied element and merge that annotation's attributes with matching attributes from annotations in lower levels of the annotation hierarchy.

Attributes from lower levels in the annotation hierarchy override attributes of the same name from higher levels, and @AliasFor semantics are fully supported, both within a single annotation and within the annotation hierarchy.

In contrast to getAllAnnotationAttributes(java.lang.reflect.AnnotatedElement, java.lang.String), the search algorithm used by this method will stop searching the annotation hierarchy once the first annotation of the specified annotationName has been found. As a consequence, additional annotations of the specified annotationName will be ignored.

This method follows find semantics as described in the class-level javadoc.

Parameters:

element - the annotated element

annotationName - the fully qualified class name of the annotation type to find

classValuesAsString - whether to convert Class references into Strings or to preserve them as Class references

nestedAnnotationsAsMap - whether to convert nested Annotation instances into AnnotationAttributes maps or to preserve them as Annotation instances

Returns:

the merged AnnotationAttributes, or null if not found

Since:

4.2

See Also:

• findMergedAnnotation(AnnotatedElement, Class)
• getMergedAnnotationAttributes(AnnotatedElement, String, boolean, boolean)

findMergedAnnotation

@Nullable
public static <A extends Annotation> A findMergedAnnotation(AnnotatedElement element,
 Class<A> annotationType)

Find the first annotation of the specified annotationType within the annotation hierarchy above the supplied element, merge that annotation's attributes with matching attributes from annotations in lower levels of the annotation hierarchy, and synthesize the result back into an annotation of the specified annotationType.

@AliasFor semantics are fully supported, both within a single annotation and within the annotation hierarchy.

This method follows find semantics as described in the class-level javadoc.

Parameters:

element - the annotated element

annotationType - the annotation type to find

Returns:

the merged, synthesized Annotation, or null if not found

Since:

4.2

See Also:

• findAllMergedAnnotations(AnnotatedElement, Class)
• findMergedAnnotationAttributes(AnnotatedElement, String, boolean, boolean)
• getMergedAnnotationAttributes(AnnotatedElement, Class)

findAllMergedAnnotations

public static <A extends Annotation> Set<A> findAllMergedAnnotations(AnnotatedElement element,
 Class<A> annotationType)

Find all annotations of the specified annotationType within the annotation hierarchy above the supplied element; and for each annotation found, merge that annotation's attributes with matching attributes from annotations in lower levels of the annotation hierarchy and synthesize the results back into an annotation of the specified annotationType.

@AliasFor semantics are fully supported, both within a single annotation and within annotation hierarchies.

This method follows find semantics as described in the class-level javadoc.

Parameters:

element - the annotated element (never null)

annotationType - the annotation type to find (never null)

Returns:

the set of all merged, synthesized Annotations found, or an empty set if none were found

Since:

4.3

See Also:

• findMergedAnnotation(AnnotatedElement, Class)
• getAllMergedAnnotations(AnnotatedElement, Class)

findAllMergedAnnotations

public static Set<Annotation> findAllMergedAnnotations(AnnotatedElement element,
 Set<Class<? extends Annotation>> annotationTypes)

Find all annotations of the specified annotationTypes within the annotation hierarchy above the supplied element; and for each annotation found, merge that annotation's attributes with matching attributes from annotations in lower levels of the annotation hierarchy and synthesize the results back into an annotation of the corresponding annotationType.

@AliasFor semantics are fully supported, both within a single annotation and within annotation hierarchies.

This method follows find semantics as described in the class-level javadoc.

Parameters:

element - the annotated element (never null)

annotationTypes - the annotation types to find

Returns:

the set of all merged, synthesized Annotations found, or an empty set if none were found

Since:

5.1

See Also:

• findAllMergedAnnotations(AnnotatedElement, Class)

findMergedRepeatableAnnotations

public static <A extends Annotation> Set<A> findMergedRepeatableAnnotations(AnnotatedElement element,
 Class<A> annotationType)

Find all repeatable annotations of the specified annotationType within the annotation hierarchy above the supplied element; and for each annotation found, merge that annotation's attributes with matching attributes from annotations in lower levels of the annotation hierarchy and synthesize the results back into an annotation of the specified annotationType.

The container type that holds the repeatable annotations will be looked up via Repeatable.

@AliasFor semantics are fully supported, both within a single annotation and within annotation hierarchies.

This method follows find semantics as described in the class-level javadoc.

Parameters:

element - the annotated element (never null)

annotationType - the annotation type to find (never null)

Returns:

the set of all merged repeatable Annotations found, or an empty set if none were found

Throws:

IllegalArgumentException - if the element or annotationType is null, or if the container type cannot be resolved

Since:

4.3

See Also:

• findMergedAnnotation(AnnotatedElement, Class)
• findAllMergedAnnotations(AnnotatedElement, Class)
• findMergedRepeatableAnnotations(AnnotatedElement, Class, Class)

findMergedRepeatableAnnotations

public static <A extends Annotation> Set<A> findMergedRepeatableAnnotations(AnnotatedElement element,
 Class<A> annotationType,
 @Nullable
 Class<? extends Annotation> containerType)

Find all repeatable annotations of the specified annotationType within the annotation hierarchy above the supplied element; and for each annotation found, merge that annotation's attributes with matching attributes from annotations in lower levels of the annotation hierarchy and synthesize the results back into an annotation of the specified annotationType.

@AliasFor semantics are fully supported, both within a single annotation and within annotation hierarchies.

This method follows find semantics as described in the class-level javadoc.

WARNING: if the supplied containerType is not null, the search will be restricted to supporting only repeatable annotations whose container is the supplied containerType. This prevents the search from finding repeatable annotations declared as meta-annotations on other types of repeatable annotations. If you need to support such a use case, favor findMergedRepeatableAnnotations(AnnotatedElement, Class) over this method or alternatively use the MergedAnnotations API directly in conjunction with RepeatableContainers that are composed to support multiple repeatable annotation types.

Parameters:

element - the annotated element (never null)

annotationType - the annotation type to find (never null)

containerType - the type of the container that holds the annotations; may be null if the container type should be looked up via Repeatable

Returns:

the set of all merged repeatable Annotations found, or an empty set if none were found

Throws:

IllegalArgumentException - if the element or annotationType is null, or if the container type cannot be resolved

AnnotationConfigurationException - if the supplied containerType is not a valid container annotation for the supplied annotationType

Since:

4.3

See Also:

• findMergedAnnotation(AnnotatedElement, Class)
• findAllMergedAnnotations(AnnotatedElement, Class)