小峰mybatis（3）mybatis分页和缓存

package com.cy.service;

import java.util.HashMap;
import java.util.List;
import java.util.Map;

import org.apache.ibatis.session.RowBounds;
import org.apache.ibatis.session.SqlSession;
import org.apache.log4j.Logger;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;

import com.cy.mapper.StudentMapper;
import com.cy.model.Student;
import com.cy.util.SqlSessionFactoryUtil;

public class StudentTest2 {
    private static Logger logger = Logger.getLogger(StudentTest2.class);
    
    private SqlSession sqlSession=null;
    private StudentMapper studentMapper=null;
    
    @Before
    public void setUp() throws Exception {
        sqlSession=SqlSessionFactoryUtil.openSession();
        studentMapper=sqlSession.getMapper(StudentMapper.class);
    }
    
    @After
    public void tearDown() throws Exception {
        sqlSession.close();
    }
    
   
    /**
     * 逻辑分页，实现过程：先把所有数据都查出来，再从内存中从0开始，取3条数据；
     */
    @Test
    public void findStudent() {
        logger.info("查询学生逻辑分页");
        int offset = 0;            //start；开始
        int limit = 3;            //limit： 每页大小；
        RowBounds rowBound = new RowBounds(offset, limit);    //RowBounds里面有分页信息
        List<Student> studentList=studentMapper.findStudent(rowBound);
        for(Student student:studentList){
            System.out.println(student);
        }
    }
    
    @Test
    public void findStudent2() {
        logger.info("查询学生物理分页");
        Map<String, Object> map = new HashMap<String, Object>();
        map.put("start", 0);
        map.put("size", 3);
        List<Student> studentList=studentMapper.findStudent2(map);
        for(Student student:studentList){
            System.out.println(student);
        }
    }
}

1 　　//逻辑分页 RowBounds里面有分页信息
2     public List<Student> findStudent(RowBounds rowBound);
3     
4     //物理分页
5     public List<Student> findStudent2(Map<String, Object> map);

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.cy.mapper.StudentMapper">

    <resultMap type="com.cy.model.Student" id="StudentResult">
        <id property="id" column="id"/>
        <result property="name" column="name"/>
        <result property="age" column="age"/>
        <result property="remark" column="remark"/>
    </resultMap>
    
    <!-- 逻辑分页 -->
    <select id="findStudent" resultMap="StudentResult">
        select * from t_student
    </select>
    
    <!-- 物理分页 -->
    <select id="findStudent2" parameterType="Map"  resultMap="StudentResult">
        select * from t_student
        <if test="start!=null and size!=null">
            limit #{start}, #{size}
        </if>
    </select>
</mapper>

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.cy.mapper.StudentMapper">
    
    <!--
        1，size:表示缓存cache中能容纳的最大元素数。默认是1024；
        2，flushInterval:定义缓存刷新周期，以毫秒计；
        3，eviction:定义缓存的移除机制；默认是LRU(least recently userd，最近最少使用),还有FIFO(first in first out，先进先出)
        4，readOnly:默认值是false，假如是true的话，缓存只能读。
     -->
    <cache size="1024" flushInterval="60000" eviction="LRU" readOnly="false"/>
    
    <resultMap type="com.cy.model.Student" id="StudentResult">
        <id property="id" column="id"/>
        <result property="name" column="name"/>
        <result property="age" column="age"/>
        <result property="remark" column="remark"/>
    </resultMap>
    
    <select id="findStudents" resultMap="StudentResult" flushCache="false" useCache="true">
        select * from t_student
    </select>
    
    <insert id="insertStudent" parameterType="Student" flushCache="true">
        insert into t_student values(null,#{name},#{age},#{pic},#{remark});
    </insert>
    
</mapper>