grails.plugin.cache.ehcache.GrailsEhcacheCacheManager.java Source code

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Here is the source code for grails.plugin.cache.ehcache.GrailsEhcacheCacheManager.java

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/* Copyright 2012 SpringSource.
 *
 * 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 grails.plugin.cache.ehcache;

import grails.plugin.cache.GrailsCacheManager;

import java.util.Collection;
import java.util.Collections;
import java.util.LinkedHashSet;
import java.util.Set;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;

import net.sf.ehcache.CacheManager;
import net.sf.ehcache.Ehcache;
import net.sf.ehcache.Status;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.cache.Cache;
import org.springframework.util.Assert;

/**
 * Based on org.springframework.cache.ehcache.EhCacheCacheManager; reworked
 * to return GrailsEhcacheCache instances.
 *
 * @author Costin Leau
 * @author Juergen Hoeller
 * @author Burt Beckwith
 */
public class GrailsEhcacheCacheManager implements GrailsCacheManager, InitializingBean {

    protected Logger log = LoggerFactory.getLogger(getClass());

    protected CacheManager cacheManager;
    protected final ConcurrentMap<String, Cache> cacheMap = new ConcurrentHashMap<String, Cache>();
    protected Set<String> cacheNames = new LinkedHashSet<String>();

    public Cache getCache(String name) {

        Cache cache = cacheMap.get(name);
        if (cache == null) {
            // check the EhCache cache again (in case the cache was added at runtime)
            Ehcache ehcache = cacheManager.getEhcache(name);
            if (ehcache == null) {
                // create a new one based on defaults
                cacheManager.addCache(name);
                ehcache = cacheManager.getEhcache(name);
            }

            cache = new GrailsEhcacheCache(ehcache);
            addCache(cache);
        }
        return cache;
    }

    public boolean cacheExists(String name) {
        return getCacheNames().contains(name);
    }

    public boolean destroyCache(String name) {
        cacheManager.removeCache(name);
        cacheMap.remove(name);
        cacheNames.remove(name);
        return true;
    }

    public Collection<String> getCacheNames() {
        return Collections.unmodifiableSet(cacheNames);
    }

    protected Collection<Cache> loadCaches() {
        Assert.notNull(cacheManager, "A backing EhCache CacheManager is required");
        Status status = cacheManager.getStatus();
        Assert.isTrue(Status.STATUS_ALIVE.equals(status),
                "An 'alive' EhCache CacheManager is required - current cache is " + status);

        String[] names = cacheManager.getCacheNames();
        Collection<Cache> caches = new LinkedHashSet<Cache>(names.length);
        for (String name : names) {
            caches.add(new GrailsEhcacheCache(cacheManager.getEhcache(name)));
        }
        return caches;
    }

    protected void addCache(Cache cache) {
        cacheMap.put(cache.getName(), cache);
        cacheNames.add(cache.getName());
    }

    /**
     * Set the backing EhCache {@link net.sf.ehcache.CacheManager}.
     */
    public void setCacheManager(CacheManager manager) {
        cacheManager = manager;
    }

    @Override
    public void afterPropertiesSet() {
        Assert.notNull(cacheManager, "A backing EhCache CacheManager is required");
        if (Status.STATUS_ALIVE != cacheManager.getStatus()) {
            // loadCaches() will assert on status, so no need to do anything here
            return;
        }

        Collection<? extends Cache> caches = loadCaches();
        // preserve the initial order of the cache names
        for (Cache cache : caches) {
            addCache(cache);
        }

        log.debug("Cache names: {}", getCacheNames());
    }
}