org.springframework.core.annotation.AnnotationsProcessor Maven / Gradle / Ivy
/*
* Copyright 2002-2019 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 org.springframework.lang.Nullable;
/**
* Callback interface used to process annotations.
*
* @param the context type
* @param the result type
* @author Phillip Webb
* @since 5.2
* @see AnnotationsScanner
* @see TypeMappedAnnotations
*/
@FunctionalInterface
interface AnnotationsProcessor {
/**
* Called when an aggregate is about to be processed. This method may return
* a {@code non-null} result to short-circuit any further processing.
* @param context context information relevant to the processor
* @param aggregateIndex the aggregate index about to be processed
* @return a {@code non-null} result if no further processing is required
*/
@Nullable
default R doWithAggregate(C context, int aggregateIndex) {
return null;
}
/**
* Called when an array of annotations can be processed. This method may
* return a {@code non-null} result to short-circuit any further processing.
* @param context context information relevant to the processor
* @param aggregateIndex the aggregate index of the provided annotations
* @param source the original source of the annotations, if known
* @param annotations the annotations to process (this array may contain
* {@code null} elements)
* @return a {@code non-null} result if no further processing is required
*/
@Nullable
R doWithAnnotations(C context, int aggregateIndex, @Nullable Object source, Annotation[] annotations);
/**
* Get the final result to be returned. By default this method returns
* the last process result.
* @param result the last early exit result, or {@code null} if none
* @return the final result to be returned to the caller
*/
@Nullable
default R finish(@Nullable R result) {
return result;
}
}