Mybatis 一级缓存（20）

Mybatis中的一级缓存和二级缓存（本博文只是针对一级缓存说明）

概述

ORM框架一般都会有缓存机制，做为其中一员的Mybatis也存在缓存。功能是用以提升查询的效率和服务给数据库带来压力。同样的Mybatis也存在有一级缓存和二级缓存，并且预留了集成第三方缓存的接口类：【cache】。

缓存角色

【一级缓存】

MyBatis默认支持一级缓存。在没有任何配置情况下，默认开启一级缓存，MyBatis 的一级缓存是在会话（SqlSession）层面进行缓存的；
如果同样SqlSession对象查询相同数据，则只会查询一次。因在第一次查询时向数据库发送SQL语句，并将查询结果放入到SQLSESSION中（作为缓存存在）。后续在此做相同对象查询时，则直接从缓存中查询该对象即可（省略了访问数据库操作，提高查询效率）；
Mybatis开启一个数据库会话时，会创建一个新的SqlSession对象表示一次数据库会话，SqlSession对象中会有一个新的Executor对象。Executor对象持有一个新的PerpetualCache对象；会话结束时，SqllSession对象及其内部的 Executor 对象还有PerpetualCache对象都会一同释放掉；
如SqlSession调用close()方法，会释放掉一级缓存PerpetualCache对象，一级缓存将不可用；
如SqlSession调用clearCache()方法，会清空PerpetualCache对象中数据，但该对象仍可使用；
SqlSession中insert、update及delete，都会清空PerpetualCache对象的数据，但该对象仍可继续使用。

一级缓存执行流程

MyBatis回话流程：当客户端开启一次数据回话SqlSession对象中创建一个本地缓存(local cache)。执行查询前尝试从本地缓存中查找是否存在，如果存在本地缓存中，就直接从缓存中取出，然后返回给客户端。否则，从数据库读取数据，将查询结果存入缓存并返回给用户。

验证（下面通过代码进行实际验证）：

1、pom文件

2、数据库配置文件

<?xml version="1.0" encoding="UTF-8"?>

<!DOCTYPE configuration

        PUBLIC "-//mybatis.org//DTD Config 3.0//EN"

        "http://mybatis.org/dtd/mybatis-3-config.dtd">

<configuration>

    <environments default="development">

        <environment id="development">

            <transactionManager type="JDBC"/>

            <dataSource type="POOLED">

                <property name="driver" value="com.mysql.jdbc.Driver"/>

                <property name="url" value="jdbc:mysql://127.0.0.1:3306/mybatis01"/>

                <property name="username" value="root"/>

                <property name="password" value="root"/>

            </dataSource>

        </environment>

    </environments>

    <mappers>

        <mapper resource="com/cache/mapper/personMapper.xml"/>

    </mappers>

</configuration>

3、实体类

public class Person {

    /* 人员ID */

    private int id;

    /* 人员名称 */

    private String name;

    /* 人员年龄 */

    private int age;

    /* 人员性别 */

    private Boolean sex;

    public Person() {

    }

    public Person(int id, String name, int age) {

        this.id = id;

        this.name = name;

        this.age = age;

    }

    public Person(int id, String name, int age, Boolean sex) {

        this.id = id;

        this.name = name;

        this.age = age;

        this.sex = sex;

    }

    public Boolean getSex() {

        return sex;

    }

    public void setSex(Boolean sex) {

        this.sex = sex;

    }

    public int getId() {

        return id;

    }

    public void setId(int id) {

        this.id = id;

    }

    public String getName() {

        return name;

    }

    public void setName(String name) {

        this.name = name;

    }

    public int getAge() {

        return age;

    }

    public void setAge(int age) {

        this.age = age;

    }

    @Override

    public String toString() {

        return "Person{" +

                "id=" + id +

                ", name='" + name + '\'' +

                ", age=" + age +

                '}';

    }

}

4、接口类

package com.cache.mapper;

import com.cache.bean.Person;

import java.util.List;

// 操作mybatis接口

public interface PersonMapper {

    /* 根据ID查询人员信息 */

    Person queryPersonById(int id);

   /*  根据ID修改人员信息 */

    void updateStudentById(Person person);

}

5、接口对应mapper类

<?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.cache.mapper.PersonMapper">

    <select id="queryPersonById" parameterType="int" resultType="com.cache.bean.Person">

        select

            id,name,age

        from

            t_person

        where

            id = #{id}

    </select>

    <update id="updateStudentById"  parameterType="com.cache.bean.Person">

        UPDATE t_person SET NAME =#{name},age = #{age} where id =#{id}

    </update>

</mapper>

6、数据库表结构和数据

7、测试类

public class test {

    /**

     * 演示一级缓存：根据ID查询人的信息

     */

    @Test

    public void test01() throws Exception{

        Reader reader = Resources.getResourceAsReader("mybatis-01.xml");

        SqlSessionFactory sessionFactory = new SqlSessionFactoryBuilder().build(reader);

        SqlSession session = sessionFactory.openSession();

        PersonMapper personMapper = session.getMapper(PersonMapper.class);

        /* 默认使用一级缓存演示 */

        Person person = personMapper.queryPersonById(1001);

        System.out.println("初次查询结果为："+person);

        Person person01 = personMapper.queryPersonById(1001);

        System.out.println("第二次查询结果为："+person);

        session.close();

}

执行结果：

"C:\Program Files\Java\jdk1.8.0_25\bin\java" -ea -Didea.test.cyclic.buffer.size=1048576 "-javaagent:C:\Users\newsoft\AppData\Roaming\JetBrains\IntelliJ IDEA 2017.3.5\lib\idea_rt.jar=28708:C:\Users\newsoft\AppData\Roaming\JetBrains\IntelliJ IDEA 2017.3.5\bin" -Dfile.encoding=UTF-8 -classpath "C:\Users\newsoft\AppData\Roaming\JetBrains\IntelliJ IDEA 2017.3.5\lib\idea_rt.jar;C:\Users\newsoft\AppData\Roaming\JetBrains\IntelliJ IDEA 2017.3.5\plugins\junit\lib\junit-rt.jar;C:\Users\newsoft\AppData\Roaming\JetBrains\IntelliJ IDEA 2017.3.5\plugins\junit\lib\junit5-rt.jar;D:\download\lib\mavenTollTransfer\mic-repository\org\junit\platform\junit-platform-launcher\1.5.2\junit-platform-launcher-1.5.2.jar;D:\download\lib\mavenTollTransfer\mic-repository\org\apiguardian\apiguardian-api\1.1.0\apiguardian-api-1.1.0.jar;D:\download\lib\mavenTollTransfer\mic-repository\org\junit\platform\junit-platform-engine\1.5.2\junit-platform-engine-1.5.2.jar;D:\download\lib\mavenTollTransfer\mic-repository\org\opentest4j\opentest4j\1.2.0\opentest4j-1.2.0.jar;D:\download\lib\mavenTollTransfer\mic-repository\org\junit\platform\junit-platform-commons\1.5.2\junit-platform-commons-1.5.2.jar;D:\download\lib\mavenTollTransfer\mic-repository\org\junit\jupiter\junit-jupiter-engine\5.5.2\junit-jupiter-engine-5.5.2.jar;D:\download\lib\mavenTollTransfer\mic-repository\org\junit\jupiter\junit-jupiter-api\5.5.2\junit-jupiter-api-5.5.2.jar;D:\download\lib\mavenTollTransfer\mic-repository\org\junit\vintage\junit-vintage-engine\5.5.2\junit-vintage-engine-5.5.2.jar;D:\download\lib\mavenTollTransfer\mic-repository\junit\junit\4.12\junit-4.12.jar;D:\download\lib\mavenTollTransfer\mic-repository\org\hamcrest\hamcrest-core\1.3\hamcrest-core-1.3.jar;C:\Program Files\Java\jdk1.8.0_25\jre\lib\charsets.jar;C:\Program Files\Java\jdk1.8.0_25\jre\lib\deploy.jar;C:\Program Files\Java\jdk1.8.0_25\jre\lib\ext\access-bridge-64.jar;C:\Program Files\Java\jdk1.8.0_25\jre\lib\ext\cldrdata.jar;C:\Program Files\Java\jdk1.8.0_25\jre\lib\ext\dnsns.jar;C:\Program Files\Java\jdk1.8.0_25\jre\lib\ext\jaccess.jar;C:\Program Files\Java\jdk1.8.0_25\jre\lib\ext\jfxrt.jar;C:\Program Files\Java\jdk1.8.0_25\jre\lib\ext\localedata.jar;C:\Program Files\Java\jdk1.8.0_25\jre\lib\ext\nashorn.jar;C:\Program Files\Java\jdk1.8.0_25\jre\lib\ext\sunec.jar;C:\Program Files\Java\jdk1.8.0_25\jre\lib\ext\sunjce_provider.jar;C:\Program Files\Java\jdk1.8.0_25\jre\lib\ext\sunmscapi.jar;C:\Program Files\Java\jdk1.8.0_25\jre\lib\ext\sunpkcs11.jar;C:\Program Files\Java\jdk1.8.0_25\jre\lib\ext\zipfs.jar;C:\Program Files\Java\jdk1.8.0_25\jre\lib\javaws.jar;C:\Program Files\Java\jdk1.8.0_25\jre\lib\jce.jar;C:\Program Files\Java\jdk1.8.0_25\jre\lib\jfr.jar;C:\Program Files\Java\jdk1.8.0_25\jre\lib\jfxswt.jar;C:\Program Files\Java\jdk1.8.0_25\jre\lib\jsse.jar;C:\Program Files\Java\jdk1.8.0_25\jre\lib\management-agent.jar;C:\Program Files\Java\jdk1.8.0_25\jre\lib\plugin.jar;C:\Program Files\Java\jdk1.8.0_25\jre\lib\resources.jar;C:\Program Files\Java\jdk1.8.0_25\jre\lib\rt.jar;D:\ideaworkspace\ProjectStudy\mybatis-cache-03\target\classes;D:\download\lib\mavenTollTransfer\mic-repository\org\hamcrest\hamcrest-core\2.1\hamcrest-core-2.1.jar;D:\download\lib\mavenTollTransfer\mic-repository\org\hamcrest\hamcrest\2.1\hamcrest-2.1.jar;D:\download\lib\mavenTollTransfer\mic-repository\org\mybatis\mybatis\3.4.5\mybatis-3.4.5.jar;D:\download\lib\mavenTollTransfer\mic-repository\mysql\mysql-connector-java\5.1.44\mysql-connector-java-5.1.44.jar;D:\download\lib\mavenTollTransfer\mic-repository\log4j\log4j\1.2.17\log4j-1.2.17.jar;D:\download\lib\mavenTollTransfer\mic-repository\org\slf4j\slf4j-log4j12\1.7.12\slf4j-log4j12-1.7.12.jar;D:\download\lib\mavenTollTransfer\mic-repository\org\slf4j\slf4j-api\1.7.30\slf4j-api-1.7.30.jar;D:\download\lib\mavenTollTransfer\mic-repository\cglib\cglib\3.3.0\cglib-3.3.0.jar;D:\download\lib\mavenTollTransfer\mic-repository\org\ow2\asm\asm\7.1\asm-7.1.jar;D:\download\lib\mavenTollTransfer\mic-repository\net\logstash\logback\logstash-logback-encoder\5.3\logstash-logback-encoder-5.3.jar;D:\download\lib\mavenTollTransfer\mic-repository\com\fasterxml\jackson\core\jackson-databind\2.10.3\jackson-databind-2.10.3.jar;D:\download\lib\mavenTollTransfer\mic-repository\com\fasterxml\jackson\core\jackson-annotations\2.10.3\jackson-annotations-2.10.3.jar;D:\download\lib\mavenTollTransfer\mic-repository\com\fasterxml\jackson\core\jackson-core\2.10.3\jackson-core-2.10.3.jar" com.intellij.rt.execution.junit.JUnitStarter -ideVersion5 -junit5 com.cache.test.test,test01

[lsjSso]2021-10-20 12:55:30,892-org.apache.ibatis.logging.LogFactory-0   [main]DEBUGorg.apache.ibatis.logging.LogFactory-Logging initialized using 'class org.apache.ibatis.logging.slf4j.Slf4jImpl' adapter.

[lsjSso]2021-10-20 12:55:31,036-org.apache.ibatis.datasource.pooled.PooledDataSource-144 [main]DEBUGorg.apache.ibatis.datasource.pooled.PooledDataSource-PooledDataSource forcefully closed/removed all connections.

[lsjSso]2021-10-20 12:55:31,037-org.apache.ibatis.datasource.pooled.PooledDataSource-145 [main]DEBUGorg.apache.ibatis.datasource.pooled.PooledDataSource-PooledDataSource forcefully closed/removed all connections.

[lsjSso]2021-10-20 12:55:31,037-org.apache.ibatis.datasource.pooled.PooledDataSource-145 [main]DEBUGorg.apache.ibatis.datasource.pooled.PooledDataSource-PooledDataSource forcefully closed/removed all connections.

[lsjSso]2021-10-20 12:55:31,037-org.apache.ibatis.datasource.pooled.PooledDataSource-145 [main]DEBUGorg.apache.ibatis.datasource.pooled.PooledDataSource-PooledDataSource forcefully closed/removed all connections.

[lsjSso]2021-10-20 12:55:31,137-org.apache.ibatis.transaction.jdbc.JdbcTransaction-245 [main]DEBUGorg.apache.ibatis.transaction.jdbc.JdbcTransaction-Opening JDBC Connection

[lsjSso]2021-10-20 12:55:31,414-org.apache.ibatis.datasource.pooled.PooledDataSource-522 [main]DEBUGorg.apache.ibatis.datasource.pooled.PooledDataSource-Created connection 52908367.

[lsjSso]2021-10-20 12:55:31,415-org.apache.ibatis.transaction.jdbc.JdbcTransaction-523 [main]DEBUGorg.apache.ibatis.transaction.jdbc.JdbcTransaction-Setting autocommit to false on JDBC Connection [com.mysql.jdbc.JDBC4Connection@327514f]

[lsjSso]2021-10-20 12:55:31,418-com.cache.mapper.PersonMapper.queryPersonById-526 [main]DEBUGcom.cache.mapper.PersonMapper.queryPersonById-==>  Preparing: select id,name,age from t_person where id = ?

[lsjSso]2021-10-20 12:55:31,459-com.cache.mapper.PersonMapper.queryPersonById-567 [main]DEBUGcom.cache.mapper.PersonMapper.queryPersonById-==> Parameters: 1001(Integer)

[lsjSso]2021-10-20 12:55:31,500-com.cache.mapper.PersonMapper.queryPersonById-608 [main]DEBUGcom.cache.mapper.PersonMapper.queryPersonById-<==      Total: 1

初次查询结果为：Person{id=1001, name='zhangsan', age=27}

第二次查询结果为：Person{id=1001, name='zhangsan', age=27}

[lsjSso]2021-10-20 12:55:31,501-org.apache.ibatis.transaction.jdbc.JdbcTransaction-609 [main]DEBUGorg.apache.ibatis.transaction.jdbc.JdbcTransaction-Resetting autocommit to true on JDBC Connection [com.mysql.jdbc.JDBC4Connection@327514f]

[lsjSso]2021-10-20 12:55:31,502-org.apache.ibatis.transaction.jdbc.JdbcTransaction-610 [main]DEBUGorg.apache.ibatis.transaction.jdbc.JdbcTransaction-Closing JDBC Connection [com.mysql.jdbc.JDBC4Connection@327514f]

[lsjSso]2021-10-20 12:55:31,502-org.apache.ibatis.datasource.pooled.PooledDataSource-610 [main]DEBUGorg.apache.ibatis.datasource.pooled.PooledDataSource-Returned connection 52908367 to pool.

Process finished with exit code 0

分析：

分析一：查询两次结果只进行一次查询

分析二：查询了两次执行结果

验证执行，commit操作后缓存失效：

第一：测试代码修改update操作后再查询两次，其他保持不变：

A、修改测试代码为：

@Test

    public void test01() throws Exception{

        Reader reader = Resources.getResourceAsReader("mybatis-01.xml");

        SqlSessionFactory sessionFactory = new SqlSessionFactoryBuilder().build(reader);

        SqlSession session = sessionFactory.openSession();

        PersonMapper personMapper = session.getMapper(PersonMapper.class);

        /* 默认使用一级缓存演示

        Person person = personMapper.queryPersonById(1001);

        System.out.println("初次查询结果为："+person);

        Person person01 = personMapper.queryPersonById(1001);

        System.out.println("第二次查询结果为："+person);

        session.close();

        */

        /* 清除缓存演示 */

        Person personFirst = personMapper.queryPersonById(1001);

        System.out.println("update执行前，操作第一次查询结果为："+personFirst);

        Person personSecond = personMapper.queryPersonById(1001);

        System.out.println("update执行前，操作第二次查询结果为："+personSecond);

        Person personEntity = new Person(1001,"HuanCun",26);

        personMapper.updateStudentById(personEntity);

        System.out.println("执行update操作，清除一级缓存！");

        session.commit();

        System.out.println("update执行后commit提交成功！");

        Person personEarCache = personMapper.queryPersonById(1001);

        System.out.println("update执行后，初次查询结果为："+personEarCache);

        Person person01 = personMapper.queryPersonById(1001);

        System.out.println("update执行后，第二次查询结果为："+person01);

        session.close();

    }

B、验证结果

"C:\Program Files\Java\jdk1.8.0_25\bin\java" -ea -Didea.test.cyclic.buffer.size=1048576 "-javaagent:C:\Users\newsoft\AppData\Roaming\JetBrains\IntelliJ IDEA 2017.3.5\lib\idea_rt.jar=13417:C:\Users\newsoft\AppData\Roaming\JetBrains\IntelliJ IDEA 2017.3.5\bin" -Dfile.encoding=UTF-8 -classpath "C:\Users\newsoft\AppData\Roaming\JetBrains\IntelliJ IDEA 2017.3.5\lib\idea_rt.jar;C:\Users\newsoft\AppData\Roaming\JetBrains\IntelliJ IDEA 2017.3.5\plugins\junit\lib\junit-rt.jar;C:\Users\newsoft\AppData\Roaming\JetBrains\IntelliJ IDEA 2017.3.5\plugins\junit\lib\junit5-rt.jar;D:\download\lib\mavenTollTransfer\mic-repository\org\junit\platform\junit-platform-launcher\1.5.2\junit-platform-launcher-1.5.2.jar;D:\download\lib\mavenTollTransfer\mic-repository\org\apiguardian\apiguardian-api\1.1.0\apiguardian-api-1.1.0.jar;D:\download\lib\mavenTollTransfer\mic-repository\org\junit\platform\junit-platform-engine\1.5.2\junit-platform-engine-1.5.2.jar;D:\download\lib\mavenTollTransfer\mic-repository\org\opentest4j\opentest4j\1.2.0\opentest4j-1.2.0.jar;D:\download\lib\mavenTollTransfer\mic-repository\org\junit\platform\junit-platform-commons\1.5.2\junit-platform-commons-1.5.2.jar;D:\download\lib\mavenTollTransfer\mic-repository\org\junit\jupiter\junit-jupiter-engine\5.5.2\junit-jupiter-engine-5.5.2.jar;D:\download\lib\mavenTollTransfer\mic-repository\org\junit\jupiter\junit-jupiter-api\5.5.2\junit-jupiter-api-5.5.2.jar;D:\download\lib\mavenTollTransfer\mic-repository\org\junit\vintage\junit-vintage-engine\5.5.2\junit-vintage-engine-5.5.2.jar;D:\download\lib\mavenTollTransfer\mic-repository\junit\junit\4.12\junit-4.12.jar;D:\download\lib\mavenTollTransfer\mic-repository\org\hamcrest\hamcrest-core\1.3\hamcrest-core-1.3.jar;C:\Program Files\Java\jdk1.8.0_25\jre\lib\charsets.jar;C:\Program Files\Java\jdk1.8.0_25\jre\lib\deploy.jar;C:\Program Files\Java\jdk1.8.0_25\jre\lib\ext\access-bridge-64.jar;C:\Program Files\Java\jdk1.8.0_25\jre\lib\ext\cldrdata.jar;C:\Program Files\Java\jdk1.8.0_25\jre\lib\ext\dnsns.jar;C:\Program Files\Java\jdk1.8.0_25\jre\lib\ext\jaccess.jar;C:\Program Files\Java\jdk1.8.0_25\jre\lib\ext\jfxrt.jar;C:\Program Files\Java\jdk1.8.0_25\jre\lib\ext\localedata.jar;C:\Program Files\Java\jdk1.8.0_25\jre\lib\ext\nashorn.jar;C:\Program Files\Java\jdk1.8.0_25\jre\lib\ext\sunec.jar;C:\Program Files\Java\jdk1.8.0_25\jre\lib\ext\sunjce_provider.jar;C:\Program Files\Java\jdk1.8.0_25\jre\lib\ext\sunmscapi.jar;C:\Program Files\Java\jdk1.8.0_25\jre\lib\ext\sunpkcs11.jar;C:\Program Files\Java\jdk1.8.0_25\jre\lib\ext\zipfs.jar;C:\Program Files\Java\jdk1.8.0_25\jre\lib\javaws.jar;C:\Program Files\Java\jdk1.8.0_25\jre\lib\jce.jar;C:\Program Files\Java\jdk1.8.0_25\jre\lib\jfr.jar;C:\Program Files\Java\jdk1.8.0_25\jre\lib\jfxswt.jar;C:\Program Files\Java\jdk1.8.0_25\jre\lib\jsse.jar;C:\Program Files\Java\jdk1.8.0_25\jre\lib\management-agent.jar;C:\Program Files\Java\jdk1.8.0_25\jre\lib\plugin.jar;C:\Program Files\Java\jdk1.8.0_25\jre\lib\resources.jar;C:\Program Files\Java\jdk1.8.0_25\jre\lib\rt.jar;D:\ideaworkspace\ProjectStudy\mybatis-cache-03\target\classes;D:\download\lib\mavenTollTransfer\mic-repository\org\hamcrest\hamcrest-core\2.1\hamcrest-core-2.1.jar;D:\download\lib\mavenTollTransfer\mic-repository\org\hamcrest\hamcrest\2.1\hamcrest-2.1.jar;D:\download\lib\mavenTollTransfer\mic-repository\org\mybatis\mybatis\3.4.5\mybatis-3.4.5.jar;D:\download\lib\mavenTollTransfer\mic-repository\mysql\mysql-connector-java\5.1.44\mysql-connector-java-5.1.44.jar;D:\download\lib\mavenTollTransfer\mic-repository\log4j\log4j\1.2.17\log4j-1.2.17.jar;D:\download\lib\mavenTollTransfer\mic-repository\org\slf4j\slf4j-log4j12\1.7.12\slf4j-log4j12-1.7.12.jar;D:\download\lib\mavenTollTransfer\mic-repository\org\slf4j\slf4j-api\1.7.30\slf4j-api-1.7.30.jar;D:\download\lib\mavenTollTransfer\mic-repository\cglib\cglib\3.3.0\cglib-3.3.0.jar;D:\download\lib\mavenTollTransfer\mic-repository\org\ow2\asm\asm\7.1\asm-7.1.jar;D:\download\lib\mavenTollTransfer\mic-repository\net\logstash\logback\logstash-logback-encoder\5.3\logstash-logback-encoder-5.3.jar;D:\download\lib\mavenTollTransfer\mic-repository\com\fasterxml\jackson\core\jackson-databind\2.10.3\jackson-databind-2.10.3.jar;D:\download\lib\mavenTollTransfer\mic-repository\com\fasterxml\jackson\core\jackson-annotations\2.10.3\jackson-annotations-2.10.3.jar;D:\download\lib\mavenTollTransfer\mic-repository\com\fasterxml\jackson\core\jackson-core\2.10.3\jackson-core-2.10.3.jar" com.intellij.rt.execution.junit.JUnitStarter -ideVersion5 -junit5 com.cache.test.test,test01

[lsjSso]2021-10-20 13:14:00,298-org.apache.ibatis.logging.LogFactory-0   [main]DEBUGorg.apache.ibatis.logging.LogFactory-Logging initialized using 'class org.apache.ibatis.logging.slf4j.Slf4jImpl' adapter.

[lsjSso]2021-10-20 13:14:00,459-org.apache.ibatis.datasource.pooled.PooledDataSource-161 [main]DEBUGorg.apache.ibatis.datasource.pooled.PooledDataSource-PooledDataSource forcefully closed/removed all connections.

[lsjSso]2021-10-20 13:14:00,459-org.apache.ibatis.datasource.pooled.PooledDataSource-161 [main]DEBUGorg.apache.ibatis.datasource.pooled.PooledDataSource-PooledDataSource forcefully closed/removed all connections.

[lsjSso]2021-10-20 13:14:00,459-org.apache.ibatis.datasource.pooled.PooledDataSource-161 [main]DEBUGorg.apache.ibatis.datasource.pooled.PooledDataSource-PooledDataSource forcefully closed/removed all connections.

[lsjSso]2021-10-20 13:14:00,460-org.apache.ibatis.datasource.pooled.PooledDataSource-162 [main]DEBUGorg.apache.ibatis.datasource.pooled.PooledDataSource-PooledDataSource forcefully closed/removed all connections.

[lsjSso]2021-10-20 13:14:00,554-org.apache.ibatis.transaction.jdbc.JdbcTransaction-256 [main]DEBUGorg.apache.ibatis.transaction.jdbc.JdbcTransaction-Opening JDBC Connection

[lsjSso]2021-10-20 13:14:00,832-org.apache.ibatis.datasource.pooled.PooledDataSource-534 [main]DEBUGorg.apache.ibatis.datasource.pooled.PooledDataSource-Created connection 52908367.

[lsjSso]2021-10-20 13:14:00,832-org.apache.ibatis.transaction.jdbc.JdbcTransaction-534 [main]DEBUGorg.apache.ibatis.transaction.jdbc.JdbcTransaction-Setting autocommit to false on JDBC Connection [com.mysql.jdbc.JDBC4Connection@327514f]

[lsjSso]2021-10-20 13:14:00,834-com.cache.mapper.PersonMapper.queryPersonById-536 [main]DEBUGcom.cache.mapper.PersonMapper.queryPersonById-==>  Preparing: select id,name,age from t_person where id = ?

[lsjSso]2021-10-20 13:14:00,869-com.cache.mapper.PersonMapper.queryPersonById-571 [main]DEBUGcom.cache.mapper.PersonMapper.queryPersonById-==> Parameters: 1001(Integer)

[lsjSso]2021-10-20 13:14:00,891-com.cache.mapper.PersonMapper.queryPersonById-593 [main]DEBUGcom.cache.mapper.PersonMapper.queryPersonById-<==      Total: 1

update执行前，操作第一次查询结果为：Person{id=1001, name='HuanCun', age=26}

update执行前，操作第二次查询结果为：Person{id=1001, name='HuanCun', age=26}

[lsjSso]2021-10-20 13:14:00,892-com.cache.mapper.PersonMapper.updateStudentById-594 [main]DEBUGcom.cache.mapper.PersonMapper.updateStudentById-==>  Preparing: UPDATE t_person SET NAME =?,age = ? where id =?

[lsjSso]2021-10-20 13:14:00,892-com.cache.mapper.PersonMapper.updateStudentById-594 [main]DEBUGcom.cache.mapper.PersonMapper.updateStudentById-==> Parameters: HuanCun(String), 26(Integer), 1001(Integer)

[lsjSso]2021-10-20 13:14:00,950-com.cache.mapper.PersonMapper.updateStudentById-652 [main]DEBUGcom.cache.mapper.PersonMapper.updateStudentById-<==    Updates: 1

执行update操作，清除一级缓存！

[lsjSso]2021-10-20 13:14:00,951-org.apache.ibatis.transaction.jdbc.JdbcTransaction-653 [main]DEBUGorg.apache.ibatis.transaction.jdbc.JdbcTransaction-Committing JDBC Connection [com.mysql.jdbc.JDBC4Connection@327514f]

update执行后commit提交成功！

[lsjSso]2021-10-20 13:14:00,953-com.cache.mapper.PersonMapper.queryPersonById-655 [main]DEBUGcom.cache.mapper.PersonMapper.queryPersonById-==>  Preparing: select id,name,age from t_person where id = ?

[lsjSso]2021-10-20 13:14:00,953-com.cache.mapper.PersonMapper.queryPersonById-655 [main]DEBUGcom.cache.mapper.PersonMapper.queryPersonById-==> Parameters: 1001(Integer)

[lsjSso]2021-10-20 13:14:00,954-com.cache.mapper.PersonMapper.queryPersonById-656 [main]DEBUGcom.cache.mapper.PersonMapper.queryPersonById-<==      Total: 1

update执行后，初次查询结果为：Person{id=1001, name='HuanCun', age=26}

update执行后，第二次查询结果为：Person{id=1001, name='HuanCun', age=26}

[lsjSso]2021-10-20 13:14:00,954-org.apache.ibatis.transaction.jdbc.JdbcTransaction-656 [main]DEBUGorg.apache.ibatis.transaction.jdbc.JdbcTransaction-Resetting autocommit to true on JDBC Connection [com.mysql.jdbc.JDBC4Connection@327514f]

[lsjSso]2021-10-20 13:14:00,955-org.apache.ibatis.transaction.jdbc.JdbcTransaction-657 [main]DEBUGorg.apache.ibatis.transaction.jdbc.JdbcTransaction-Closing JDBC Connection [com.mysql.jdbc.JDBC4Connection@327514f]

[lsjSso]2021-10-20 13:14:00,955-org.apache.ibatis.datasource.pooled.PooledDataSource-657 [main]DEBUGorg.apache.ibatis.datasource.pooled.PooledDataSource-Returned connection 52908367 to pool.

Process finished with exit code 0

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