cachekeyfactory.java

Java/J2EE框架Jdon-Framework系统的Sample

/**
 * Copyright 2005 Jdon.com
 * 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 com.jdon.controller.cache;

import java.util.*;
import com.jdon.util.Debug;
/**
 * 由于不能直接将数据ID作为Key保存到缓存中，因为可能ID数值重复，
 * 因此必须将ID转换成CacheKey，再保存到缓存中。 *
 * ID就是dataKey
 *
 * 子类：
 * com.jdon.model.cache.ModelCacheKeyFactory
 * com.jdon.model.query.PageCacheKeyFactory
 *
 * <p>Copyright: Jdon.com Copyright (c) 2003</p>
 * <p></p>
 * @author banq
 * @version 1.0
 */
public abstract class CacheKeyFactory {
  public final static String module = CacheKeyFactory.class.getName();

  protected CacheFactory cacheFactory;

  public CacheKeyFactory(CacheFactory cacheFactory){
    this.cacheFactory = cacheFactory;
  }

  public CacheKey createCacheKey(Object dataKey, String typeName) {
    CacheKey cacheKey = createCacheKeyImp(dataKey, typeName);
    if (dataKey != null)
       cacheFactory.getCacheKeyMap().put(cacheKey.toString(), dataKey.toString());
    return cacheKey;
  }

  public abstract CacheKey createCacheKeyImp(Object dataKey, String typeName);


  public void removeCacheKey(String cacheKeyStr){
     cacheFactory.getCacheKeyMap().remove(cacheKeyStr);
  }

  /**
    * 寻找所有与dataKey相关的CacheKey，宁多勿少。
    * @param dataKey
    * @return Collection
    */
   public Collection getAllCacheKey(Object dataKey){

     String cacheKey = null;
     String dataTmpKey = null;
     Collection list = new ArrayList();

     Map map = cacheFactory.getCacheKeyMap();
     Iterator iter = map.keySet().iterator();
     while(iter.hasNext()){
        cacheKey = (String)iter.next();
        dataTmpKey = (String)map.get(cacheKey);
        if (dataTmpKey.equals(dataKey)){
           list.add(cacheKey);
        }
     }
     return list;
   }


}