/*
 * JBoss, Home of Professional Open Source
 * Copyright 2012, Red Hat, Inc., and individual contributors
 * by the @authors tag. See the copyright.txt in the distribution for a
 * full listing of individual contributors.
 *
 * 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.
 */
package org.jboss.weld.resources;

import java.lang.annotation.Annotation;
import java.lang.reflect.AnnotatedElement;

import org.jboss.weld.exceptions.WeldException;
import org.jboss.weld.metadata.TypeStore;

/**
 * {@link ReflectionCache} implementation that works around possible deadlocks in HotSpot:
 *
 * @see https://issues.jboss.org/browse/WELD-1169
 * @see http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=7122142
 * @see http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=6588239
 *
 * @author Jozef Hartinger
 *
 */
public class HotspotReflectionCache extends DefaultReflectionCache {

    private final Class<?> annotationTypeLock;

    public HotspotReflectionCache(TypeStore store) {
        super(store);
        try {
            this.annotationTypeLock = Class.forName("sun.reflect.annotation.AnnotationType");
        } catch (ClassNotFoundException e) {
            throw new WeldException(e);
        }
    }

    @Override
    protected Annotation[] internalGetAnnotations(AnnotatedElement element) {
        if (element instanceof Class<?>) {
            Class<?> clazz = (Class<?>) element;
            if (clazz.isAnnotation()) {
                synchronized (annotationTypeLock) {
                    return element.getAnnotations();
                }
            }
        }
        return element.getAnnotations();
    }
}