org.springframework.core.annotation

## 类 AnnotatedElementUtils

- java.lang.Object
- - org.springframework.core.annotation.AnnotatedElementUtils

-     public 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`.

  从以下版本开始:
    4.0
  作者:
    Phillip Webb, Juergen Hoeller, Sam Brannen
  另请参阅:
    `AliasFor`, `AnnotationAttributes`, `AnnotationUtils`, `BridgeMethodResolver`

- - ### 构造器概要

    构造器
    构造器和说明
    `AnnotatedElementUtils()`

  - ### 方法概要

    所有方法 静态方法 具体方法
    限定符和类型 | 方法和说明
    --- | ---
    `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 <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 <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.

    - ### 从类继承的方法 java.lang.Object

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

- - ### 构造器详细资料

    - #### AnnotatedElementUtils

          public AnnotatedElementUtils()

  - ### 方法详细资料

    - #### forAnnotations

          public static AnnotatedElement forAnnotations(Annotation... annotations)

      Build an adapted `AnnotatedElement` for the given annotations, typically for use with other methods on `AnnotatedElementUtils`.
      参数:
        `annotations` - the annotations to expose through the `AnnotatedElement`
      从以下版本开始:
        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.

      参数:
        `element` - the annotated element
        `annotationType` - the annotation type on which to find meta-annotations
      返回:
        the names of all meta-annotations present on the annotation, or `null` if not found
      从以下版本开始:
        4.2
      另请参阅:
        `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.

      参数:
        `element` - the annotated element
        `annotationName` - the fully qualified class name of the annotation type on which to find meta-annotations
      返回:
        the names of all meta-annotations present on the annotation, or an empty set if none found
      另请参阅:
        `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.

      参数:
        `element` - the annotated element
        `annotationType` - the meta-annotation type to find
      返回:
        `true` if a matching meta-annotation is present
      从以下版本开始:
        4.2.3
      另请参阅:
        `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.

      参数:
        `element` - the annotated element
        `annotationName` - the fully qualified class name of the meta-annotation type to find
      返回:
        `true` if a matching meta-annotation is present
      另请参阅:
        `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.

      参数:
        `element` - the annotated element
        `annotationType` - the annotation type to find
      返回:
        `true` if a matching annotation is present
      从以下版本开始:
        4.2.3
      另请参阅:
        `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.

      参数:
        `element` - the annotated element
        `annotationName` - the fully qualified class name of the annotation type to find
      返回:
        `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)`.

      参数:
        `element` - the annotated element
        `annotationType` - the annotation type to find
      返回:
        the merged `AnnotationAttributes`, or `null` if not found
      从以下版本开始:
        4.2
      另请参阅:
        `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`.

      参数:
        `element` - the annotated element
        `annotationName` - the fully qualified class name of the annotation type to find
      返回:
        the merged `AnnotationAttributes`, or `null` if not found
      从以下版本开始:
        4.2
      另请参阅:
        `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.

      参数:
        `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
      返回:
        the merged `AnnotationAttributes`, or `null` if not found
      从以下版本开始:
        4.2
      另请参阅:
        `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.

      This method delegates to `getMergedAnnotationAttributes(AnnotatedElement, Class)` and `AnnotationUtils.synthesizeAnnotation(Map, Class, AnnotatedElement)`.

      参数:
        `element` - the annotated element
        `annotationType` - the annotation type to find
      返回:
        the merged, synthesized `Annotation`, or `null` if not found
      从以下版本开始:
        4.2
      另请参阅:
        `getMergedAnnotationAttributes(AnnotatedElement, Class)`, `findMergedAnnotation(AnnotatedElement, Class)`, `AnnotationUtils.synthesizeAnnotation(Map, Class, AnnotatedElement)`

    - #### 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.

      参数:
        `element` - the annotated element (never `null`)
        `annotationType` - the annotation type to find (never `null`)
      返回:
        the set of all merged, synthesized `Annotations` found, or an empty set if none were found
      从以下版本开始:
        4.3
      另请参阅:
        `getMergedAnnotation(AnnotatedElement, Class)`, `getAllAnnotationAttributes(AnnotatedElement, String)`, `findAllMergedAnnotations(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.

      参数:
        `element` - the annotated element (never `null`)
        `annotationType` - the annotation type to find (never `null`)
      返回:
        the set of all merged repeatable `Annotations` found, or an empty set if none were found
      抛出:
        `IllegalArgumentException` - if the `element` or `annotationType` is `null`, or if the container type cannot be resolved
      从以下版本开始:
        4.3
      另请参阅:
        `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.

      参数:
        `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`
      返回:
        the set of all merged repeatable `Annotations` found, or an empty set if none were found
      抛出:
        `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`
      从以下版本开始:
        4.3
      另请参阅:
        `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.

      参数:
        `element` - the annotated element
        `annotationName` - the fully qualified class name of the annotation type to find
      返回:
        a `MultiValueMap` keyed by attribute name, containing the annotation attributes from all annotations found, or `null` if not found
      另请参阅:
        `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.

      参数:
        `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
      返回:
        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.

      参数:
        `element` - the annotated element
        `annotationType` - the annotation type to find
      返回:
        `true` if a matching annotation is present
      从以下版本开始:
        4.3
      另请参阅:
        `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.

      参数:
        `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
      返回:
        the merged `AnnotationAttributes`, or `null` if not found
      从以下版本开始:
        4.2
      另请参阅:
        `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.

      参数:
        `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
      返回:
        the merged `AnnotationAttributes`, or `null` if not found
      从以下版本开始:
        4.2
      另请参阅:
        `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.

      参数:
        `element` - the annotated element
        `annotationType` - the annotation type to find
      返回:
        the merged, synthesized `Annotation`, or `null` if not found
      从以下版本开始:
        4.2
      另请参阅:
        `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.

      参数:
        `element` - the annotated element (never `null`)
        `annotationType` - the annotation type to find (never `null`)
      返回:
        the set of all merged, synthesized `Annotations` found, or an empty set if none were found
      从以下版本开始:
        4.3
      另请参阅:
        `findMergedAnnotation(AnnotatedElement, Class)`, `getAllMergedAnnotations(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.

      参数:
        `element` - the annotated element (never `null`)
        `annotationType` - the annotation type to find (never `null`)
      返回:
        the set of all merged repeatable `Annotations` found, or an empty set if none were found
      抛出:
        `IllegalArgumentException` - if the `element` or `annotationType` is `null`, or if the container type cannot be resolved
      从以下版本开始:
        4.3
      另请参阅:
        `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.

      参数:
        `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`
      返回:
        the set of all merged repeatable `Annotations` found, or an empty set if none were found
      抛出:
        `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`
      从以下版本开始:
        4.3
      另请参阅:
        `findMergedAnnotation(AnnotatedElement, Class)`, `findAllMergedAnnotations(AnnotatedElement, Class)`