org.springframework.core.annotation.AnnotationAttributeExtractor Maven / Gradle / Ivy
/*
* Copyright 2002-2017 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* https://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.springframework.core.annotation;
import java.lang.annotation.Annotation;
import java.lang.reflect.Method;
import org.springframework.lang.Nullable;
/**
* An {@code AnnotationAttributeExtractor} is responsible for
* {@linkplain #getAttributeValue extracting} annotation attribute values
* from an underlying {@linkplain #getSource source} such as an
* {@code Annotation} or a {@code Map}.
*
* @author Sam Brannen
* @since 4.2
* @param the type of source supported by this extractor
* @see SynthesizedAnnotationInvocationHandler
*/
interface AnnotationAttributeExtractor {
/**
* Get the type of annotation that this extractor extracts attribute
* values for.
*/
Class getAnnotationType();
/**
* Get the element that is annotated with an annotation of the annotation
* type supported by this extractor.
* @return the annotated element, or {@code null} if unknown
*/
@Nullable
Object getAnnotatedElement();
/**
* Get the underlying source of annotation attributes.
*/
S getSource();
/**
* Get the attribute value from the underlying {@linkplain #getSource source}
* that corresponds to the supplied attribute method.
* @param attributeMethod an attribute method from the annotation type
* supported by this extractor
* @return the value of the annotation attribute
*/
@Nullable
Object getAttributeValue(Method attributeMethod);
}