本文主要讲一讲Hibernate+EhCache配置二级缓存的基本使用方法,主要分以下两个方面介绍:
(有关EhCache的基础介绍可参见:http://sjsky.iteye.com/blog/1288257 )
[一]、Cache的多种配置方法
Javabean cache的配置有三种,下面将一一介绍,具体如下::
(1).bean中注解配置的方式: @Cache(usage = CacheConcurrencyStrategy.READ_WRITE)
(2).hibernate.cfg.xml中标签配置方式: <class-cache class="" usage="" />
(3).映射文件*.hb.xml中标签配置方式: <cache usage=" />
1. classpath:ehcahce.xml配置文件如下:
<?xml version="1.0" encoding="UTF-8"?> <ehcache xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="ehcache.xsd" updateCheck="true" monitoring="autodetect" dynamicConfig="true"> <diskStore path="java.io.tmpdir"/> <transactionManagerLookup class="net.sf.ehcache.transaction.manager.DefaultTransactionManagerLookup" properties="jndiName=java:/TransactionManager" propertySeparator=";"/> <cacheManagerEventListenerFactory class="" properties=""/> <defaultCache maxElementsInMemory="100" eternal="false" timeToIdleSeconds="120" timeToLiveSeconds="120" overflowToDisk="true" diskSpoolBufferSizeMB="30" maxElementsOnDisk="100" diskPersistent="false" diskExpiryThreadIntervalSeconds="120" memoryStoreEvictionPolicy="LRU" statistics="false" /> <cache name="org.hibernate.cache.StandardQueryCache" maxElementsInMemory="5" eternal="false" timeToLiveSeconds="120" overflowToDisk="true" /> <cache name="org.hibernate.cache.UpdateTimestampsCache" maxElementsInMemory="5000" eternal="true" overflowToDisk="true" /> <cache name="sampleCache1" maxElementsInMemory="10000" maxElementsOnDisk="1000" eternal="false" overflowToDisk="true" diskSpoolBufferSizeMB="20" timeToIdleSeconds="300" timeToLiveSeconds="600" memoryStoreEvictionPolicy="LFU" transactionalMode="off" /> <cache name="sampleCache2" maxElementsInMemory="1000" eternal="true" overflowToDisk="false" memoryStoreEvictionPolicy="FIFO" /> </ehcache>
2.hibernate配置文件:hibernate.cfg.xml
<!DOCTYPE hibernate-configuration
PUBLIC "-//Hibernate/Hibernate Configuration DTD//EN"
"http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
<session-factory>
<property name="connection.driver_class">
oracle.jdbc.driver.OracleDriver
</property>
<property name="connection.url">
jdbc:oracle:thin:@localhost:1521:ora11g
</property>
<property name="connection.username">mytest</property>
<property name="connection.password">111111</property>
<property name="dialect">
org.hibernate.dialect.Oracle9Dialect
</property>
<property name="connection.useUnicode">true</property>
<property name="connection.characterEncoding">UTF-8</property>
<property name="connection.SetBigStringTryClob">true</property>
<property name="connection.pool_size">10</property>
<property name="hibernate.jdbc.batch_size">10</property>
<property name="show_sql">true</property>
<property name="format_sql">false</property>
<property name="current_session_context_class">thread</property>
<property name="hbm2ddl.auto">update</property>
<!-- Hibernate 3.3 and higher -->
<!--
<property name="hibernate.cache.region.factory_class">
net.sf.ehcache.hibernate.EhCacheRegionFactory
</property>
<property name="hibernate.cache.region.factory_class">
net.sf.ehcache.hibernate.SingletonEhCacheRegionFactory
</property>
-->
<!-- hibernate3.0-3.2 cache config-->
<!--
<property name="hibernate.cache.region.factory_class">
net.sf.ehcache.hibernate.EhCacheProvider
</property>
-->
<property name="hibernate.cache.provider_class">
net.sf.ehcache.hibernate.SingletonEhCacheProvider
</property>
<!-- Enable Second-Level Cache and Query Cache Settings -->
<property name="hibernate.cache.use_second_level_cache">
true
</property>
<property name="hibernate.cache.use_query_cache">
true
</property>
<!-- 注解配置 -->
<mapping class="michael.cache.ehcache.hibernate.EhUserInfo" />
<mapping class="michael.cache.ehcache.hibernate.EhBlogTopic" />
<mapping class="michael.cache.ehcache.hibernate.EhBlogTopic2" />
<!-- 映射文件 -->
<mapping
resource="michael/cache/ehcache/hibernate/tb_EhBlogTopic3.hb.xml" />
<!-- class-cache config -->
<class-cache class="michael.cache.ehcache.hibernate.EhBlogTopic"
usage="read-write" />
</session-factory>
</hibernate-configuration>
3.相关javabean代码片段如下:
(1).hibernate.cfg.xml中<calss-cache>标签配置的:EhBlogTopic.java:
/**
* @blog http://sjsky.iteye.com
* @author Michael
*/
@Entity
@Table(name = "MY_TB_EH_BLOG_TOPIC")
public class EhBlogTopic implements Serializable {
/**
* serialVersionUID
*/
private static final long serialVersionUID = -570936907944909799L;
private Integer id;
private String userId;
private String topic;
private String site;
//其他省略
}
(2). bean中注解的方式配置cache的:EhBlogTopic2.java
/**
* @blog http://sjsky.iteye.com
* @author Michael
*/
@Entity
@Table(name = "MY_TB_EH_BLOG_TOPIC2")
@Cache(usage = CacheConcurrencyStrategy.READ_WRITE)
public class EhBlogTopic2 implements Serializable {
//属性和EhBlogTopic一样
//其他省略
}
(3). 映射文件*.hb.xml中添加cache标签的: EhBlogTopic3.java
/**
* @blog http://sjsky.iteye.com
* @author Michael
*/
public class EhBlogTopic3 implements Serializable {
//属性和EhBlogTopic一样
//其他省略
}
tb_EhBlogTopic3.hb.xml
<?xml version="1.0"?> <!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 2.0//EN" "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd"> <hibernate-mapping package="michael.cache.ehcache.hibernate"> <class name="EhBlogTopic3" table="MY_TB_EH_BLOG_TOPIC3"> <cache usage="read-write" /> <id name="id" type="int" unsaved-value="null"> <generator class="increment" /> </id> <property name="userId" column="USER_ID" type="string" not-null="false" length="20" /> <property name="topic" column="TOPIC" type="string" not-null="false" length="100" /> <property name="site" column="SITE" type="string" not-null="false" length="100" /> </class> </hibernate-mapping>
(4). 没有配置cache的bean:EhUserInfo.java
/**
* @blog http://sjsky.iteye.com
* @author Michael
*/
@Entity
@Table(name = "MY_TB_EH_USER_INFO")
public class EhUserInfo implements Serializable {
/**
* serialVersionUID
*/
private static final long serialVersionUID = 930384253681679239L;
private Integer id;
private String userId;
private String userName;
private String otherInfo;
/**
* @return the id
*/
@Id
@GeneratedValue
@Column(name = "ID")
public Integer getId() {
return id;
}
//其他省略。。。
}
4.测试运行代码如下:
package michael.cache.ehcache.hibernate;
import java.util.List;
import michael.hibernate.bigstring.oracle.BigStrBlob;
import net.sf.ehcache.Cache;
import net.sf.ehcache.CacheManager;
import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.AnnotationConfiguration;
import org.hibernate.cfg.Configuration;
/**
*
* @blog http://sjsky.iteye.com
* @author Michael
*/
public class TestEhcacheHibernate {
/**
* @param args
*/
@SuppressWarnings("unchecked")
public static void main(String[] args) {
testMulitConfigMethod();
}
/**
* 测试多种配置缓存的方法
*/
public static void testMulitConfigMethod() {
SessionFactory sessionFactory = null;
try {
System.out.println("ehcache - hibernate Test ...");
Configuration config = new AnnotationConfiguration()
.configure("michael/cache/ehcache/hibernate/hibernate.cfg.xml");
System.out.println("hibernate config successful :" + config);
sessionFactory = config.buildSessionFactory();
Transaction ta = null;
try {
Session session = sessionFactory.getCurrentSession();
ta = session.beginTransaction();
} catch (Exception e) {
e.printStackTrace();
ta.rollback();
}
String[] cacheNames = CacheManager.getInstance().getCacheNames();
System.out.println("缓存的key cacheNames length := "
+ cacheNames.length + " 具体详细列表如下:");
for (String name : cacheNames) {
System.out.println("name := " + name);
}
} catch (Exception e) {
e.printStackTrace();
}
System.out.println("ehcache - hibernate Test end.");
}
}
运行结果如下:
ehcache - hibernate Test ...
从运行结果可见:三种方式的缓存配置都已经成功。
[二]、Hibernate+EhCache集成demo
1.分别初始化EhUserInfo(没有配置cache的)和EhBlogTopic(配置过cache的)数据如下:
EhUserInfo:

EhBlogTopic:

2.演示代码:
package michael.cache.ehcache.hibernate;
import java.util.List;
import michael.hibernate.bigstring.oracle.BigStrBlob;
import net.sf.ehcache.Cache;
import net.sf.ehcache.CacheManager;
import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.AnnotationConfiguration;
import org.hibernate.cfg.Configuration;
/**
*
* @blog http://sjsky.iteye.com
* @author Michael
*/
public class TestEhcacheHibernate {
/**
* @param args
*/
@SuppressWarnings("unchecked")
public static void main(String[] args) {
SessionFactory sessionFactory = null;
try {
System.out.println("ehcache - hibernate Test ...");
Configuration config = new AnnotationConfiguration()
.configure("michael/cache/ehcache/hibernate/hibernate.cfg.xml");
sessionFactory = config.buildSessionFactory();
System.out.println("buildSessionFactory===============");
System.out.println("====================================");
System.out.println("session open ....");
System.out.println("同一个session(一级缓存默认的)中,没有配置cache的Bean");
Transaction ta = null;
try {
Session session = sessionFactory.getCurrentSession();
String hsql = "select t from EhUserInfo t ";
ta = session.beginTransaction();
Query query = session.createQuery(hsql);
System.out.println("查询全部query.list().size:"
+ query.list().size());
System.out.println("再根据ID=1查询某记录时不会再去查数据库,故不会打印hsql");
EhUserInfo vo1 = (EhUserInfo) session.get(EhUserInfo.class, 1);
System.out.println("根据ID=1找到的记录:" + vo1);
ta.commit();
} catch (Exception e) {
e.printStackTrace();
ta.rollback();
}
System.out.println("session closed.");
System.out.println("session open ....");
try {
Session session = sessionFactory.getCurrentSession();
ta = session.beginTransaction();
System.out.println("第一次根据ID=1查询某记录时,会打印hsql");
EhUserInfo vo1 = (EhUserInfo) session.get(EhUserInfo.class, 1);
System.out.println("根据ID=1找到的记录:" + vo1);
ta.commit();
} catch (Exception e) {
e.printStackTrace();
ta.rollback();
}
System.out.println("session closed.");
System.out.println("====================================");
System.out.println("当前同一个sessionFactory,没有配置cache的Bean,");
System.out.println("session open ....");
try {
Session session = sessionFactory.getCurrentSession();
ta = session.beginTransaction();
System.out.println("第一次根据ID=1查询记录时会再去查数据库,故打印hsql如下:");
EhUserInfo vo1 = (EhUserInfo) session.get(EhUserInfo.class, 1);
System.out.println("根据ID=1找到的记录:" + vo1);
ta.commit();
} catch (Exception e) {
e.printStackTrace();
ta.rollback();
}
System.out.println("session closed.");
System.out.println("====================================");
String[] cacheNames = CacheManager.getInstance().getCacheNames();
System.out.println("缓存的key cacheNames length := "
+ cacheNames.length);
for (String name : cacheNames) {
System.out.println("name := " + name);
}
System.out.println("====================================");
System.out.println("同一个session(一级缓存默认的)中,配置cache的Bean");
System.out.println("session open ....");
try {
Session session = sessionFactory.getCurrentSession();
String hsql = "select t from EhBlogTopic t ";
ta = session.beginTransaction();
Query query = session.createQuery(hsql);
query.setCacheable(true);
System.out.println("查询全部query.list().size:"
+ query.list().size());
Cache myCache1 = CacheManager.getInstance().getCache(
"michael.cache.ehcache.hibernate.EhBlogTopic");
System.out.println("查询到EhBlogTopic cache size:"
+ myCache1.getKeys().size());
myCache1 = CacheManager.getInstance().getCache(
"michael.cache.ehcache.hibernate.EhBlogTopic");
System.out.println("EhBlogTopic cache size:"
+ myCache1.getKeys().size() + ",详细记录如下:");
for (Object str : myCache1.getKeys()) {
System.out.println(str);
}
System.out
.println("在同一个session,再根据ID=1查询记录时不会再去查数据库,故不会打印hsql");
EhBlogTopic vo1 = (EhBlogTopic) session.get(EhBlogTopic.class,
1);
System.out.println("根据ID=1找到的记录:" + vo1);
EhBlogTopic vo2 = new EhBlogTopic();
vo2.setId(10);
vo2.setUserId("michael");
vo2.setTopic("Myblog:11");
vo2.setSite("http://sjsky.iteye.com");
session.save(vo2);
ta.commit();
System.out.println("新增加一条记录ID=10");
} catch (Exception e) {
e.printStackTrace();
ta.rollback();
}
System.out.println("session closed.");
System.out.println("====================================");
Cache myCache1 = CacheManager.getInstance().getCache(
"michael.cache.ehcache.hibernate.EhBlogTopic");
System.out.println("EhBlogTopic cache size:"
+ myCache1.getKeys().size() + ",详细记录如下:");
for (Object str : myCache1.getKeys()) {
System.out.println(str);
}
System.out.println("====================================");
System.out.println("在当前同一个sessionFactory,配置cache的bean");
System.out.println("session open ....");
try {
Session session = sessionFactory.getCurrentSession();
ta = session.beginTransaction();
System.out
.println("不管是否第一次查询ID=1的记录,如果cache中存在的,则不会再查数据库,故不打印hsql");
EhBlogTopic vo1 = (EhBlogTopic) session.get(EhBlogTopic.class,
1);
System.out.println("根据ID=1找到的记录:" + vo1);
System.out.println("查询之前session保存的数据ID=10,也不会再查数据库,故不打印hsql");
EhBlogTopic vo2 = (EhBlogTopic) session.get(EhBlogTopic.class,
10);
System.out.println("根据之前save的ID=10找到的记录:" + vo2);
ta.commit();
} catch (Exception e) {
e.printStackTrace();
ta.rollback();
}
System.out.println("session closed.");
} catch (Exception e) {
e.printStackTrace();
} finally {
if (null != sessionFactory) {
sessionFactory.close();
}
}
System.out.println("sessionFactory closed.");
}
}
运行结果如下:
ehcache - hibernate Test ...
我们从上面的详细运行日志中就可以看出cache的效果。
本文连接:http://sjsky.iteye.com/blog/1312132
转载请注明来自:Michael's blog @ http://sjsky.iteye.com
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