/** * 缓存池
* @author xiaoquan
* @create 2015年3月13日 上午10:32:13
* @see
*/
public class CachePool {
private static CachePool instance;//缓存池唯一实例
private static Map<String,Object> cacheItems;//缓存Map
private CachePool(){
cacheItems = new HashMap<String,Object>();
}
/**
* 得到唯一实例
* @return
*/
public synchronized static CachePool getInstance(){
if(instance == null){
instance = new CachePool();
}
return instance;
}
/**
* 清除所有Item缓存
*/
public synchronized void clearAllItems(){
cacheItems.clear();
}
/**
* 获取缓存实体
* @param name
* @return
*/
public synchronized Object getCacheItem(String name){
if(!cacheItems.containsKey(name)){
return null;
}
CacheItem cacheItem = (CacheItem) cacheItems.get(name);
if(cacheItem.isExpired()){
return null;
}
return cacheItem.getEntity();
}
/**
* 存放缓存信息
* @param name
* @param obj
* @param expires
*/
public synchronized void putCacheItem(String name,Object obj,long expires){
if(!cacheItems.containsKey(name)){
cacheItems.put(name, new CacheItem(obj, expires));
}
CacheItem cacheItem = (CacheItem) cacheItems.get(name);
cacheItem.setCreateTime(new Date());
cacheItem.setEntity(obj);
cacheItem.setExpireTime(expires);
}
public synchronized void putCacheItem(String name,Object obj){
putCacheItem(name,obj,-1);
}
/**
* 移除缓存数据
* @param name
*/
public synchronized void removeCacheItem(String name){
if(!cacheItems.containsKey(name)){
return;
}
cacheItems.remove(name);
}
/**
* 获取缓存数据的数量
* @return
*/
public int getSize(){
return cacheItems.size();
}
}public class CacheItem {
private Date createTime = new Date();//创建缓存的时间
private long expireTime = 1;//缓存期满的时间
private Object entity;//缓存的实体
public CacheItem(Object obj,long expires){
this.entity = obj;
this.expireTime = expires;
}
public boolean isExpired(){
return (expireTime != -1 && new Date().getTime()-createTime.getTime() > expireTime);
}
/**
* 省略getter、setter方法
*/
} |
原文： http://www.cnblogs.com/quanenmin/p/4335278.html