用java实现cache

在开发项目工程时，经常会遇到保存某些值放到系统的cache中，现用Cache.java和CacheManager.java来管理。具体代码分别如下：
public class Cache {
       
private String key;
       
private Object value;
       
private long timeOut;
       
private boolean expired;
       
public Cache() {
               
super();
        }
                
        public Cache(String key, String
value, long timeOut, boolean expired) {
               
this.key = key;
               
this.value = value;
               
this.timeOut = timeOut;
               
this.expired = expired;
        }
       
public String getKey() {
               
return key;
        }
       
public long getTimeOut() {
               
return timeOut;
        }
        public
Object getValue() {
               
return value;