MyBatis缓存

小配置

<?xml version="1.0" encoding="UTF-8" ?><!--头文件--><!DOCTYPE mapper        PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"        "http://mybatis.org/dtd/mybatis-3-mapper.dtd"><mapper namespace="cn.happy.dao.ITeacherDAO">     <resultMap id="teacherMapper" type="Teacher">          <id column="tid" property="tid"></id>         <result column="tname" property="tname"/>         <!--集合-->         <collection property="stus" ofType="Student">             <id column="sid" property="sid"></id>             <result column="sname" property="sname"/>         </collection>     </resultMap>    <select id="getStudentsByTeaderId" resultMap="teacherMapper">         select student.sid,sname,teacher.tid,tname        from student,teacher_student,teacher        where student.sid=teacher_student.sid         and  teacher.tid=teacher_student.tid         and  teacher.tid=#{tid}    </select></mapper>

<?xml version="1.0" encoding="UTF-8" ?><!--头文件--><!DOCTYPE mapper        PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"        "http://mybatis.org/dtd/mybatis-3-mapper.dtd"> <!--namespace：     命名空间：区分不同空间下的同名SQLID     A： findlAll     B:  findAll    --><mapper namespace="cn.happy.dao.IStudentInfoDAO">    <!--       eviction：将对象从缓存中清理出去的策略：先进，先被清理       flushInterval ：缓存对象的过期时间       readOnly:是否只读       size :对象个数    -->    <cache eviction="FIFO" flushInterval="60000" readOnly="true" size="10"/>    <!--SQL标签      id:唯一锁定到SQL标识      paramenterType:SQL语句的入参  可以省略      resultType：      增删除操作：不能 写      查询：单个实体的类型    -->    <sql id="columns">        stuid,stuname,stuage,studate    </sql>    <resultMap id="studentMap" type="StudentInfo">      <!--   <result column="stuname2" property="stuName"></result>-->    </resultMap>    <select id="findAll" resultMap="studentMap">        /*SQL文：SQL语句*/        select <include refid="columns"></include> from studentinfo    </select>

单侧

package cn.happy.test;import cn.happy.dao.*;import cn.happy.entity.*;import cn.happy.util.MyBatisUtil;import org.apache.ibatis.session.SqlSession;import org.junit.Test;import java.util.Date;import java.util.List;/** * Created by Happy on 2017-07-09. */public class MyBatisTest0716 {    //03.二级缓存    @Test    public void testsecondLevelCache() {        SqlSession session = MyBatisUtil.getSession();        IStudentInfoDAO dao = session.getMapper(IStudentInfoDAO.class);        StudentInfo stu = dao.getStudentById(8);        System.out.println(stu.getStuName());        StudentInfo s1=new StudentInfo();        s1.setStuAge(20);        s1.setStuName("2号");        s1.setStuDate(new Date());        dao.addStudent(s1);        session.close();        SqlSession session2 = MyBatisUtil.getSession();        IStudentInfoDAO dao2 = session2.getMapper(IStudentInfoDAO.class);        System.out.println("---------------------");        StudentInfo stu2 = dao2.getStudentById(8);        System.out.println(stu2.getStuName());        session2.close();        SqlSession session3 = MyBatisUtil.getSession();        IStudentInfoDAO dao3 = session3.getMapper(IStudentInfoDAO.class);        System.out.println("-----------------");        StudentInfo stu3 = dao3.getStudentById(8);        System.out.println(stu3.getStuName());        session3.close();    }    //02.增删改对一级缓存的影响    @Test    public void testUpdateHasSomeThingToOneLevelCache() {        SqlSession session = MyBatisUtil.getSession();        IStudentInfoDAO dao = session.getMapper(IStudentInfoDAO.class);        StudentInfo stu = dao.getStudentById(8);        System.out.println(stu.getStuName());        StudentInfo s1=new StudentInfo();        s1.setStuAge(20);        s1.setStuName("栋哥2号");        s1.setStuDate(new Date());        dao.addStudent(s1);        System.out.println("-------------------");        StudentInfo stu2 = dao.getStudentById(8);        System.out.println(stu2.getStuName());    }    //02.一级缓存存在性的证明    @Test    public void testOneLevelCache() {        SqlSession session = MyBatisUtil.getSession();        IStudentInfoDAO dao = session.getMapper(IStudentInfoDAO.class);        StudentInfo stu = dao.getStudentById(8);        System.out.println(stu.getStuName());        System.out.println("------------------");        StudentInfo stu2 = dao.getStudentById(8);        System.out.println(stu2.getStuName());    }}}}