Hibernate使用WebSphere分布式缓存(DistributedMap)的实现

约定

本文的实现环境是

hibernate 3.3.1

WebSphere 6.1.0.21

 

其他版本应该可以有相同或类似路径和实现方式(具体请查看其用户手册）

具体步骤

• 登陆控制台

      http://serverIP:9060/ibm/console 

 

•  控制台路径：

      资源 ==> 高速缓存实例 ==> 对象高速缓存实例

•  新建对象缓存

               名称： HibernateCache

               JNDI名称： services/cache/hibernate

               高速缓存大小： 20000(根据需要而定）

               缺省优先级别：1

              

• 应用并保存到主配置
• 创建hibernate 的Cache实现类

package com.achievo.framework.cache;

import java.util.Collections;
import java.util.HashMap;
import java.util.Map;
import org.hibernate.cache.Cache;
import org.hibernate.cache.CacheException;
import org.hibernate.cache.Timestamper;
import com.ibm.websphere.cache.DistributedMap;
/*
 * @author xhm(hyamine)
 */
public class AchievoCache implements Cache {
	private final DistributedMap distMap;
	private final String regionName;
	
	public AchievoCache(DistributedMap distMap,String regionName) {
		this.distMap = distMap;
		this.regionName = regionName;
	}


	public void clear() throws CacheException {
		distMap.clear();		
	}

	public void destroy() throws CacheException {
		
	}

	public Object get(Object key) throws CacheException {
		return distMap.get(key);
	}

	public long getElementCountInMemory() {
		return distMap.size();
	}

	public long getElementCountOnDisk() {
		return 0;
	}

	public String getRegionName() {
		return regionName;
	}

	public long getSizeInMemory() {
		return -1;
	}

	public int getTimeout() {
		return Timestamper.ONE_MS * 60000; //ie. 60 seconds
	}

	public void lock(Object key) throws CacheException {
		
		
	}

	public long nextTimestamp() {
		return Timestamper.next();
	}

	public void put(Object key, Object value) throws CacheException {
		distMap.put(key, value);
		
	}

	public Object read(Object key) throws CacheException {
		return distMap.get(key);
	}

	public void remove(Object key) throws CacheException {
		distMap.remove(key);
		
	}

	public Map toMap() {
		return Collections.unmodifiableMap(distMap);
	}

	public void unlock(Object key) throws CacheException {
			
	}

	public void update(Object key, Object value) throws CacheException {
		put(key, value);
		
	}
	public String toString() {
		return "DistributedMap(" + regionName + ')';
	}

}

 

• 创建hibernate的CacheProvider实现类

package com.achievo.framework.cache;

import java.util.Properties;

import javax.naming.InitialContext;
import javax.naming.NamingException;

import org.hibernate.cache.Cache;
import org.hibernate.cache.CacheException;
import org.hibernate.cache.CacheProvider;
import org.hibernate.cache.Timestamper;
import com.ibm.websphere.cache.DistributedMap;
/*
 * @author xhm(hyamine)
 */
public class AchievoCacheProvider implements CacheProvider{
	private static DistributedMap distMap;

	public Cache buildCache(String regionName, Properties properties)
			throws CacheException {
		if(distMap == null) {
			try {
				distMap = (DistributedMap)new InitialContext().lookup("java:comp/env/cache/hibernate");
			} catch (NamingException e) {
				e.printStackTrace();
				throw new CacheException(e);			
			}
			
		}
		return new AchievoCache(distMap,regionName);
	}

	public boolean isMinimalPutsEnabledByDefault() {
		return false;
	}

	public long nextTimestamp() {
		return Timestamper.next();
	}

	public void start(Properties properties) throws CacheException {
		
		
	}

	public void stop() {
		
		
	}
	
}

•  hibernate缓存配置

hibernate.cache.use_second_level_cache ==> true

hibernate.cache.provider_class ==> com.achievo.framework.cache.AchievoCacheProvider

 

• 资源引用

                 ibm-web-bnd.xmi

<?xml version="1.0" encoding="UTF-8"?>
<webappbnd:WebAppBinding xmi:version="2.0" xmlns:xmi="http://www.omg.org/XMI" xmlns:webappbnd="webappbnd.xmi" xmi:id="WebAppBinding_1237946146690" virtualHostName="default_host">
  <webapp href="WEB-INF/web.xml#WebApp_1237946146690"/>
  <resRefBindings xmi:id="ResourceRefBinding_1238122581168" jndiName="services/cache/hibernate">
    <bindingResourceRef href="WEB-INF/web.xml#ResourceRef_1238122581168"/>
 </resRefBindings>
</webappbnd:WebAppBinding>

                 web.xml

	<resource-ref id="ResourceRef_1238122581168">
	  <res-ref-name>cache/hibernate</res-ref-name>
	  <res-type>com.ibm.websphere.cache.DistributedMap</res-type>
	  <res-auth>Container</res-auth>  
	  <res-sharing-scope>Shareable</res-sharing-scope>
	</resource-ref>

 

 

 

 

参考文献

 

1. http://www.ibm.com/developerworks/websphere/techjournal/0609_alcott/0609_alcott.html
2. http://publib.boulder.ibm.com/infocenter/wasinfo/v6r1/index.jsp?topic=/com.ibm.websphere.base.doc/info/aes/ae/tdyn_distmap.html