broker-core/src/main/java/org/apache/qpid/server/virtualhost/CacheFactory.java

/*
 *
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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.apache.qpid.server.virtualhost;

import java.security.AccessController;

import javax.security.auth.Subject;

import com.google.common.cache.Cache;

import org.apache.qpid.server.security.QpidPrincipal;

public class CacheFactory
{

    public static <K, V> Cache<K, V> getCache(final String cacheName, final Cache<K, V> defaultCache)
    {
        Cache<K, V> cache = defaultCache;
        Subject subject = Subject.getSubject(AccessController.getContext());
        if (subject != null)
        {
            VirtualHostPrincipal
                    principal = QpidPrincipal.getSingletonPrincipal(subject, true, VirtualHostPrincipal.class);

            if (principal != null && principal.getVirtualHost() instanceof CacheProvider)
            {
                CacheProvider cacheProvider = (CacheProvider) principal.getVirtualHost();
                cache = cacheProvider.getNamedCache(cacheName);
            }
        }
        return cache;
    }
}