java 缓存框架java caching system使用示例

 要使用java caching system，需要下面这几个包：jcs.jar，concurrent.jar,commons-logging.jar, commons-lang.jar,commons-collection.jar这几个包，在java工程里面，

首先新建一个使用jcs的配置文件：cache.ccf，文件名不能改。

# DEFAULT CACHE REGION
# sets the default aux value for any non configured caches
jcs.default=
jcs.default.cacheattributes=org.apache.jcs.engine.CompositeCacheAttributes
jcs.default.cacheattributes.MaxObjects=2000
jcs.default.cacheattributes.MemoryCacheName=org.apache.jcs.engine.memory.lru.LRUMemoryCache
jcs.default.elementattributes.IsEternal=false
jcs.default.elementattributes.MaxLifeSeconds=3600
jcs.default.elementattributes.IdleTime=1800
jcs.default.elementattributes.IsSpool=true
jcs.default.elementattributes.IsRemote=true
jcs.default.elementattributes.IsLateral=true

# CACHE REGIONS AVAILABLE
# Regions preconfigured for caching
jcs.region.bookCache=
jcs.region.bookCache.cacheattributes=org.apache.jcs.engine.CompositeCacheAttributes
jcs.region.bookCache.cacheattributes.MaxObjects=1200
jcs.region.bookCache.cacheattributes.MemoryCacheName=org.apache.jcs.engine.memory.lru.LRUMemoryCache
jcs.region.bookCache.elementattributes.IsEternal=false
jcs.region.bookCache.elementattributes.MaxLifeSeconds=7200
jcs.region.bookCache.elementattributes.IdleTime=1800
jcs.region.bookCache.elementattributes.IsSpool=true
jcs.region.bookCache.elementattributes.IsRemote=true
jcs.region.bookCache.elementattributes.IsLateral=true
# AUXILIARY CACHES AVAILABLE
# Primary Disk Cache -- faster than the rest because of memory key storage
jcs.auxiliary.DC=org.apache.jcs.auxiliary.disk.indexed.IndexedDiskCacheFactory
jcs.auxiliary.DC.attributes=org.apache.jcs.auxiliary.disk.indexed.IndexedDiskCacheAttributes
jcs.auxiliary.DC.attributes.DiskPath=/usr/opt/bookstore/raf
jcs.auxiliary.DC.attributes.MaxPurgatorySize=10000
jcs.auxiliary.DC.attributes.MaxKeySize=10000
jcs.auxiliary.DC.attributes.OptimizeAtRemoveCount=300000
jcs.auxiliary.DC.attributes.MaxRecycleBinSize=7500

 

 

然后新建两个类，

import java.io.Serializable;
import java.util.List;
public class Student implements Serializable{
    /**
	 * 
	 */
	public static final long serialVersionUID = 1L;
	public int sno;
	public String sname;
	
	
	public Student()
	{}
	public int getSno(){
     return this.sno;
    }
    public void setSno(int no){
     this.sno=no;
    }
    public String getSname(){
     return this.sname;
    }
    public void setSname(String name){
     this.sname=name;
    }
}

 

 

import org.apache.jcs.JCS;
public class StuObjManager {
	private static StuObjManager instance;
	private static int checkedOut=0;
	public static JCS stuCache;
	private StuObjManager()
	{
		try
		{
			stuCache=JCS.getInstance("stuCache");
		}
		catch(Exception e)
		{
			e.printStackTrace();
		}
	}
	
	public static StuObjManager getInstance()
	{
		synchronized(StuObjManager.class)
		{
			if(instance==null)
			{
				instance=new StuObjManager();
			}
			
		}
		synchronized(instance)
		{
			instance.checkedOut++;
		}
		return instance;
	}
	
	public Student getStu(int sno)
	{
	  return getStu(sno,true);	
	}
	public Student getStu(int sno,boolean a)
	{
		Student stu=null;
		if(a)
		{
			stu=(Student)stuCache.get("Stu"+sno);
		}
		if(stu==null)
		{
              stu=loadStu(sno);
		}
		return stu;
	}
	public Student loadStu(int sno)
	{
		Student stu=new Student();
		stu.sno=sno;
		try
		{
			boolean found=false;
			found=true;
			if(found)
			{
				stuCache.put("Stu"+sno, stu);
			}
		}
		catch(Exception e)
		{System.out.println("又报错了!");}
		return stu;
	}
	
	public void storeStu(Student stu)
	{
		try
		{
			if(stu.sno!=0)
			{
				stuCache.remove("Stu"+stu.sno);
			}
			stuCache.put("Stu"+stu.sno, stu);
		}
		catch(Exception e)
		{}
	}
	public static void main(String [] args)
	{
		long last=System.currentTimeMillis();
		StuObjManager stu=StuObjManager.getInstance();
		for(int i = 0; i < 2000; i++){
			stu.loadStu(i);
		}
		Student stu1=stu.getStu(8,true);
		System.out.println(stu1.sno);
		System.out.println("所需时间："+(System.currentTimeMillis()-last));
	}
}

 

运行类StuObjManager里面的main函数，结果如下：

8
所需时间：1250