Java Reflection Annotation getAnnotation(Class clazz, Class annotClass, boolean forceInherit)

License

Declaration

public static <A extends Annotation> A getAnnotation(Class<?> clazz, Class<A> annotClass,
            boolean forceInherit) 

Method Source Code

//package com.java2s;
/*//from  ww w  .  j av  a  2  s .c  o m
 * Copyright 2011 Google Inc.
 *
 * 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
 *
 * http://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.
 */

import java.lang.annotation.Annotation;
import java.lang.annotation.Inherited;
import java.util.Arrays;
import java.util.LinkedList;

public class Main {
    public static <A extends Annotation> A getAnnotation(Class<?> clazz, Class<A> annotClass,
            boolean forceInherit) {
        boolean inherited = forceInherit || annotClass.isAnnotationPresent(Inherited.class);
        LinkedList<Class<?>> workQueue = new LinkedList<Class<?>>();
        workQueue.add(clazz);
        while (!workQueue.isEmpty()) {
            clazz = workQueue.removeFirst();
            A result = clazz.getAnnotation(annotClass);
            if (result != null || !inherited) {
                return result;
            }
            Class<?> superClass = clazz.getSuperclass();
            if (superClass != null) {
                workQueue.addLast(superClass);
            }
            workQueue.addAll(Arrays.asList((Class<?>[]) clazz.getInterfaces()));
        }
        return null;
    }
}

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