hibernate二级缓存(xml写法)

如果想使用二级缓存的话，要使用jar文件，maven导入下面这个代码

<!-- 二级缓存导的包 -->        <dependency>            <groupId>org.hibernate</groupId>            <artifactId>hibernate-ehcache</artifactId>            <version>5.0.7.Final</version>        </dependency>

在hibernate.cfg.xml中配置

<?xml version="1.0" encoding="UTF-8"?><!DOCTYPE hibernate-configuration PUBLIC"-//Hibernate/Hibernate Configuration DTD 3.0//EN""http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd"><hibernate-configuration>    <session-factory>        <property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>        <property name="hibernate.connection.url">jdbc:mysql://localhost:3306/sxt</property>        <property name="hibernate.connection.username">root</property>        <property name="hibernate.connection.password">123456</property>        <property name="hibernate.dialect">org.hibernate.dialect.MySQL5Dialect</property>        <property name="hibernate.show_sql">true</property>        <!-- 启用二级缓存 -->        <property name="cache.use_second_level_cache">true</property>        <!-- 配置二级缓存的区域 -->        <property name="cache.region.factory_class">org.hibernate.cache.ehcache.EhCacheRegionFactory</property>        <mapping class="com.sxt.beans.Buser" />        <mapping resource="com/sxt/beans/Right.hbm.xml" />        <mapping resource="com/sxt/beans/Role.hbm.xml" />        <mapping resource="com/sxt/beans/User.hbm.xml" />    </session-factory></hibernate-configuration>

还要声明你要开启那个bean的二级缓存，也就是你要在bean对应的.hbm.xml中配置上这个话<cache usage="read-write" />
下面这个就是在userbean对应的User.hbm.xml文件中配置的

<?xml version="1.0" encoding="UTF-8"?><!DOCTYPE hibernate-mapping PUBLIC"-//Hibernate/Hibernate Mapping DTD 3.0//EN""http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd"><!-- 用户表 --><hibernate-mapping>    <class name="com.sxt.beans.User" table="t_user">    <!-- 声明配置的是读和写 -->        <cache usage="read-write" />        <id name="userid">            <generator class="identity"></generator>        </id>        <property name="userName"></property>        <property name="userPass"></property>        <!-- 和权限表之间的关系 -->        <many-to-one name="role" column="roleld" class="com.sxt.beans.Role"></many-to-one>    </class></hibernate-mapping>

测试

package com.sxt.test;import org.hibernate.Session;import org.hibernate.SessionFactory;import org.hibernate.Transaction;import org.hibernate.boot.MetadataSources;import org.hibernate.boot.registry.StandardServiceRegistryBuilder;import org.hibernate.service.ServiceRegistry;import com.sxt.beans.User;/** * 二级缓存 *  * @author Administrator *  */public class Test {    public static void main(String[] args) {        ServiceRegistry serviceRegistry = new StandardServiceRegistryBuilder()                .configure().build();        // 获取sessionFactory对象        SessionFactory sessionFactory = new MetadataSources(serviceRegistry)                .buildMetadata().buildSessionFactory();        // 获取会话对象        Session session = sessionFactory.openSession();        Transaction tran = session.beginTransaction();        User u = session.get(User.class, 5);        System.out.println(u.getUserName());        tran.commit();        session.close();        Session session1 = sessionFactory.openSession();        Transaction tran1 = session1.beginTransaction();        User u2 = session1.get(User.class, 5);        System.out.println(u2.getUserName());        tran1.commit();        session1.close();    }}

//测试，如果第二次查询的时候没有去数据库查询， 就说明配置成功了，注意是生成了两个session 不是两个sessionFactory，二级缓存的数据就是存在sessionFactory里面的