org.ambraproject.admin.service.impl.CacheServiceImpl.java Source code

Introduction

Here is the source code for org.ambraproject.admin.service.impl.CacheServiceImpl.java

Source

/**
 * $HeadURL$
 * $Id$
 *
 * Copyright (c) 2006-2010 by Public Library of Science
 * http://www.plos.org
 *
 * 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.ambraproject.admin.service.impl;

import net.sf.ehcache.CacheManager;
import net.sf.ehcache.Ehcache;
import net.sf.ehcache.Element;
import net.sf.ehcache.Statistics;
import org.springframework.beans.factory.annotation.Required;
import org.ambraproject.admin.service.CacheService;

import java.util.List;
import java.util.SortedMap;
import java.util.TreeMap;

/**
 * Service class for admin cache actions
 *
 * @author russ
 */
public class CacheServiceImpl implements CacheService {

    private CacheManager cacheManager;

    /**
     * get cache stats data for display by manageCaches.ftl
     *
     * @return SortedMap of strings
     */
    public SortedMap<String, String[]> getCacheData() {
        SortedMap<String, String[]> cacheStats = new TreeMap<String, String[]>();
        // header row
        cacheStats.put("", new String[] { "Size #/Objects", "Hits (Memory/Disk)", "Misses", "Eternal (TTI/TTL)",
                "Disk Overflow/Persistent", });

        final String[] cacheNames = cacheManager.getCacheNames();
        for (final String displayName : cacheNames) {
            final Ehcache cache = cacheManager.getEhcache(displayName);
            final Statistics statistics = cache.getStatistics();
            cacheStats.put(displayName, new String[] {
                    String.valueOf(cache.getSize()) + " / " + String.valueOf(statistics.getObjectCount()),
                    String.valueOf(statistics.getCacheHits()) + " ( " + String.valueOf(statistics.getInMemoryHits())
                            + " / " + String.valueOf(statistics.getOnDiskHits()) + " )",
                    String.valueOf(statistics.getCacheMisses()),
                    String.valueOf(cache.getCacheConfiguration().isEternal()) + " ( "
                            + String.valueOf(cache.getCacheConfiguration().getTimeToIdleSeconds()) + " / "
                            + String.valueOf(cache.getCacheConfiguration().getTimeToLiveSeconds()) + " )",
                    String.valueOf(cache.getCacheConfiguration().isOverflowToDisk()) + " / "
                            + String.valueOf(cache.getCacheConfiguration().isDiskPersistent()) });
        }

        return cacheStats;
    }

    /**
     * Remove all keys from a cache
     *
     * @param cacheName the name of the cache to removeAll from
     */
    public void removeAllKeys(String cacheName) {
        Ehcache cache = cacheManager.getEhcache(cacheName);
        cache.removeAll();
    }

    /**
     * Remove a key from a cache
     *
     * @param cacheName Which cache to act on
     * @param cacheKey Which key to act on
     * @return True if the key was successfully removed
     */
    public boolean removeSingleKey(String cacheName, String cacheKey) {
        Ehcache cache = cacheManager.getEhcache(cacheName);
        return cache.remove(cacheKey);
    }

    /**
     * Clear cache statistics
     *
     * @param cacheName Which cache to act on
     */
    public void clearStatistics(String cacheName) {
        Ehcache cache = cacheManager.getEhcache(cacheName);
        cache.clearStatistics();
    }

    /**
     *
     * Return the value of a single cache key
     *
     * @param cacheName Which cache to act on
     * @param cacheKey Which key to act on
     * @return the value of the cache object
     */
    public Object getSingleKey(String cacheName, String cacheKey) {
        Ehcache cache = cacheManager.getEhcache(cacheName);
        Element elem = cache.get(cacheKey);
        return (elem == null) ? null : elem.getObjectValue();
    }

    /**
     * Return a list of all keys in a cache
     *
     * @param cacheName Which cache to act on
     * @return a list of keys in the cache
     */
    public List getAllKeys(String cacheName) {
        Ehcache cache = cacheManager.getEhcache(cacheName);
        return cache.getKeysNoDuplicateCheck();
    }

    @Required
    public void setCacheManager(CacheManager cm) {
        this.cacheManager = cm;
    }
}