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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:
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:
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:
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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