Hibernate二级缓存配置

实体类

package cn.happy.entity;

public class Emp {
    private Integer empNo;     
    private String empName;
    public Integer getEmpNo() {
        return empNo;
    }
    public void setEmpNo(Integer empNo) {
        this.empNo = empNo;
    }
    public String getEmpName() {
        return empName;
    }
    public void setEmpName(String empName) {
        this.empName = empName;
    }
    
    

}

工具类

package cn.happy.util;

import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.cfg.Configuration;

public class HibernateUtil {
    private static final ThreadLocal sessionTL=new ThreadLocal();
    private static Configuration cf;
    private static final SessionFactory factory;
    static{
        try {
            cf=new Configuration().configure();
            factory=cf.buildSessionFactory();
        } catch (Exception e) {
            throw new ExceptionInInitializerError(e);
        }
    }
    public static Session getSession()
    {    
        //sessionTL的get()方法根据当前线程返回其对应的线程内部变量，
                //也就是我们需要的Session，多线程情况下共享数据库连接是不安全的。
                //ThreadLocal保证了每个线程都有自己的Session。
        Session session = (Session)sessionTL.get();
        //如果session为null，则打开一个新的session
        if (session==null) {
            //创建一个数据库连接对象session
            session=factory.openSession();
            //保存该数据库连接session到ThreadLocal中。
            sessionTL.set(session);
            
        }
        //如果当前线程已经访问过数据库了，
                //则从sessionTL中get()就可以获取该线程上次获取过的数据库连接对象。
                return session; 
    }
    /**
     * 关闭Session
     */
    public static void closeSession()
    {
        Session session =(Session)sessionTL.get();
        sessionTL.set(null);
        session.close();
    }

}

测试类

package cn.happy.test;

import org.hibernate.Session;
import org.hibernate.Transaction;
import org.junit.Test;

import cn.happy.entity.Emp;
import cn.happy.util.HibernateUtil;

public class STest {
    Transaction tx;
    Session session;
    Transaction tx2;
    Session session2;
     @Test
       public void testBulk(){
            session = HibernateUtil.getSession();
            tx=session.beginTransaction();
           Emp emp = (Emp)session.get(Emp.class, 1);
           System.out.println(emp);
           tx.commit();
           HibernateUtil.closeSession();
           System.out.println("===================");
           session2 = HibernateUtil.getSession();
            tx2=session2.beginTransaction();
           Emp emp2 = (Emp)session2.get(Emp.class, 1);
           System.out.println(emp2);
           tx2.commit();
           HibernateUtil.closeSession();
       }
    }

小配置

<?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">
    <hibernate-mapping package="cn.happy.entity">
     <class name="Emp" table="Emp">
     <cache usage="read-write"/>
         <id name="empNo" type="int" column="EMPNO">
         <generator class="native">
         </generator>
        </id>
         <property name="empName" type="string" column="EMPNAME"/>
     </class>    
 </hibernate-mapping>

大配置

<?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="connection.driver_class">oracle.jdbc.OracleDriver</property>
    <property name="connection.url">jdbc:oracle:thin:@localhost:1521:orcl</property>
    <property name="connection.username">zc</property>
        <property name="connection.password">zc</property>
        <!-- 输出所有 SQL 语句到控制台。 -->
        <property name="hibernate.show_sql">true</property>
        <!-- 配置Hibernate.cfg.xml开启二级缓存。 -->
          <property name="hibernate.cache.use_second_level_cache">true</property>
          <!-- 配置二级缓存的供应商 -->
        <property name="hibernate.cache.provider_class">org.hibernate.cache.EhCacheProvider</property>
        
        <!-- 在 log 和 console 中打印出更漂亮的 SQL。 -->
        <property name="hibernate.format_sql">true</property>
        <!-- 自动生成数据表，update/create -->
        <property name="hbm2ddl.auto">update</property>
        <!-- 方言 -->
        <property name="hibernate.dialect">    org.hibernate.dialect.Oracle10gDialect</property>
        <!-- 关联小配置 -->
        
        <mapping resource="cn/happy/entity/Emp.hbm.xml"/>
        <class-cache    usage="read-write" class="cn.happy.entity.Emp"/>
    </session-factory>
    </hibernate-configuration>

Jar包导入

package cn.happy.entity;
public class Emp {private Integer empNo; private String empName;public Integer getEmpNo() {return empNo;}public void setEmpNo(Integer empNo) {this.empNo = empNo;}public String getEmpName() {return empName;}public void setEmpName(String empName) {this.empName = empName;}
}