使用JCS快速搭建緩存環境

# DEFAULT  CACHE REGION

jcs.default=

jcs.default.cacheattributes=org.apache.jcs.engine.CompositeCacheAttributes

jcs.default.cacheattributes.MaxObjects=1000

jcs.default.cacheattributes.MemoryCacheName=org.apache.jcs.engine.memory.lru.LRUMemoryCache

這里需要注意的是，等號“=”之后不要留空格，否則cache.ccf不會識別。

五、開始使用JCS編程

5.1創建CacheWrapper類，使用其添加對象、獲取對象和移除對象。

package com.favccxx.favjcs;
import org.apache.jcs.JCS;
import org.apache.jcs.access.exception.CacheException;
import org.apache.jcs.engine.CacheElement;
public class CacheWrapper {

    public JCS jcsCache = null;

    public CacheWrapper(JCS cache){
        this.jcsCache = cache;
    }

    public void put(String key , Object value){
        try{
            jcsCache.put(key, value);
        }catch(CacheException e){
            e.printStackTrace();
        }
    }

    public Object get(String key){
        CacheElement cacheElement = (CacheElement) jcsCache.getCacheElement(key);
        if (null != cacheElement) {
            Object object = cacheElement.val;
            return object;
        }
        return null;
    }

}

5.2創建CacheFactory類，使用工廠管理緩存對象，用以初始化緩存和清理緩存。

package com.favccxx.favjcs;
import java.util.HashMap;
import java.util.Map;
import org.apache.jcs.JCS;
import org.apache.jcs.access.exception.CacheException;
import org.apache.log4j.Logger;
public class CacheFactory {

    private static Logger logger = Logger.getLogger(CacheFactory.class);

    private static Map<String, CacheWrapper> hashMapWrapper = new HashMap<String, CacheWrapper>();

    /**
     * 獲取一個名稱為cacheName的緩存對象；如果不存在，返回null
     * @param cacheName
     * @return
     */
    public static CacheWrapper getCacheWrapper(String cacheName){
        logger.debug("Get CacheWrapper, The cacheName is : " + cacheName);
        return hashMapWrapper.get(cacheName);
    }

    /**
     * 清理所有的緩存
     */
    public static void clearCache(){
        Object[] cacheArray = hashMapWrapper.keySet().toArray();
        for(int i=0, l=cacheArray.length; i<l; i++){
            try {
                String cacheName = cacheArray[i].toString();
                logger.debug("The cache is below to clear, And the name is : " + cacheName);
                CacheWrapper cacheWrapper = hashMapWrapper.get(cacheName);
                cacheWrapper.jcsCache.clear();
            } catch (CacheException e) {
                logger.debug("Clear Cache Error!");
                e.printStackTrace();
            }
        }
    }

    /**
     * 獲取一個名稱為cacheName的緩存對象；如果不存在，則創建一個新的緩存對象
     * @param cacheName
     * @return
     */
    private static CacheWrapper createCacheWrapper(String cacheName){
        JCS cache = null;
        try{
            cache = JCS.getInstance(cacheName);
            return new CacheWrapper(cache);
        }catch(CacheException e){
            return null;
        }
    }

    /**
     * 創建緩存對象
     * @param cacheName
     */
    private static void createHashMapWrapper(String cacheName){
        hashMapWrapper.put(cacheName, createCacheWrapper(cacheName));
    }

    /**
     * 初始化緩存對象
     */
    public static void initCache(){
        logger.debug("By Start initCache Method, We create all the Cache Object");
        createHashMapWrapper("coolBoyCache");
//      createHashMapWrapper("beautifulGirl");
    }
}

5.3創建測試類TestCache，測試剛才的緩存對象。

package com.favccxx.favjcs.web;
import com.favccxx.favjcs.CacheFactory;
public class TestCache {
    /**
     * @param args
     */
    public static void main(String[] args) {
        CacheFactory.initCache();
        CacheFactory.getCacheWrapper("coolBoy");
    }
}