mybatis-SecondLevel-Cache-annotation

mybatis-SecondLevel-Cache-annotation

1.pom

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.lq</groupId>
    <artifactId>mybatis-annotation</artifactId>
    <version>1.0-SNAPSHOT</version>
    <packaging>jar</packaging>
    <dependencies>
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.4.5</version>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.6</version>
        </dependency>
        <dependency>
            <groupId>log4j</groupId>
            <artifactId>log4j</artifactId>
            <version>1.2.12</version>
        </dependency>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.10</version>
        </dependency>
    </dependencies>

</project>

2.UserDao

package com.lq.dao;

import com.lq.domain.User;
import org.apache.ibatis.annotations.*;
import org.apache.ibatis.mapping.FetchType;

import java.util.List;

/**
 * @ProjectName: mybatis-annotation
 * @Package: com.lq.dao
 * @ClassName: UserDao
 * @Author: liqiang
 * @Date: 2020/2/20 0020 17:46
 * @Version: 1.0
 */
@CacheNamespace(blocking = true) //开启二级缓存
public interface UserDao {
    @Select(value = "select * from user")
    @Results(id="userMap",value={
            @Result(id=true,column = "id",property = "id"),
            @Result(column = "username",property = "username"),
            @Result(column = "address",property = "address"),
            @Result(column = "sex",property = "sex"),
            @Result(column = "birthday",property = "birthday"),
            @Result(property = "accounts",column = "id",
                    many = @Many(select = "com.lq.dao.AccountDao.findByUid",
                            fetchType = FetchType.LAZY))
    })
    List<User> findAll();

    @Select("select * from user  where id=#{id} ")
    User findById(Integer userId);

    @Select("select * from user where username like #{username} ")
    List<User> findUserByName(String username);
}

3.User

package com.lq.domain;

import java.io.Serializable;
import java.util.Date;
import java.util.List;

/**
 * @ProjectName: mybatis-annotation
 * @Package: com.lq.domain
 * @ClassName: User
 * @Author: liqiang
 * @Date: 2020/2/20 0020 17:40
 * @Version: 1.0
 */
public class User implements Serializable {
    private Integer id;
    private String username;
    private Date birthday;
    private String sex;
    private String address;

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    public Date getBirthday() {
        return birthday;
    }

    public void setBirthday(Date birthday) {
        this.birthday = birthday;
    }

    public String getSex() {
        return sex;
    }

    public void setSex(String sex) {
        this.sex = sex;
    }

    public String getAddress() {
        return address;
    }

    public void setAddress(String address) {
        this.address = address;
    }

    @Override
    public String toString() {
        return "User{" +
                "id=" + id +
                ", username='" + username + '\'' +
                ", birthday=" + birthday +
                ", sex='" + sex + '\'' +
                ", address='" + address + '\'' +
                '}';
    }
}

4.jdbcConfig.properties

jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/eesy
jdbc.username=root
jdbc.password=root

5.log4j.properties

# Set root category priority to INFO and its only appender to CONSOLE.
#log4j.rootCategory=INFO, CONSOLE            debug   info   warn error fatal
log4j.rootCategory=debug, CONSOLE, LOGFILE

# Set the enterprise logger category to FATAL and its only appender to CONSOLE.
log4j.logger.org.apache.axis.enterprise=FATAL, CONSOLE

# CONSOLE is set to be a ConsoleAppender using a PatternLayout.
log4j.appender.CONSOLE=org.apache.log4j.ConsoleAppender
log4j.appender.CONSOLE.layout=org.apache.log4j.PatternLayout
log4j.appender.CONSOLE.layout.ConversionPattern=%d{ISO8601} %-6r [%15.15t] %-5p %30.30c %x - %m\n

# LOGFILE is set to be a File appender using a PatternLayout.
log4j.appender.LOGFILE=org.apache.log4j.FileAppender
log4j.appender.LOGFILE.File=d:\axis.log
log4j.appender.LOGFILE.Append=true
log4j.appender.LOGFILE.layout=org.apache.log4j.PatternLayout
log4j.appender.LOGFILE.layout.ConversionPattern=%d{ISO8601} %-6r [%15.15t] %-5p %30.30c %x - %m\n

6.SqlMapConfig.xml

<?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>
    <!-- 配置properties-->
    <properties resource="jdbcConfig.properties"></properties>
    <!--开启缓存，一级缓存是默认开启的-->
    <settings>
       <setting name="cacheEnabled" value="true"/>
    </settings>
    <!--使用typeAliases配置别名，它只能配置domain中类的别名 -->
    <typeAliases>
        <package name="com.lq.domain"></package>
    </typeAliases>

    <!--配置环境-->
    <environments default="mysql">
        <!-- 配置mysql的环境-->
        <environment id="mysql">
            <!-- 配置事务 -->
            <transactionManager type="JDBC"></transactionManager>

            <!--配置连接池-->
            <dataSource type="POOLED">
                <property name="driver" value="${jdbc.driver}"></property>
                <property name="url" value="${jdbc.url}"></property>
                <property name="username" value="${jdbc.username}"></property>
                <property name="password" value="${jdbc.password}"></property>
            </dataSource>
        </environment>
    </environments>
    <!-- 配置映射文件的位置 -->
    <mappers>
        <package name="com.lq.dao"></package>
    </mappers>
</configuration>

7.MyTest

package com.lq.test;

import com.lq.dao.UserDao;
import com.lq.domain.User;
import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;

import java.io.InputStream;
/**
 * @ProjectName: mybatis-annotation
 * @Package: com.lq.test
 * @ClassName: MyTest
 * @Author: liqiang
 * @Date: 2020/2/20 0020 17:57
 * @Version: 1.0
 */
public class MyTest {
    private InputStream in;
    SqlSessionFactory factory;

    @Before//用于在测试方法执行之前执行
    public void init()throws Exception{
        //1.读取配置文件，生成字节输入流
        in = Resources.getResourceAsStream("SqlMapConfig.xml");
        //2.获取SqlSessionFactory
        factory = new SqlSessionFactoryBuilder().build(in);
    }

    @After//用于在测试方法执行之后执行
    public void destroy()throws Exception{
        in.close();
    }
    @Test
    public void testSecondLevelCache() {
        SqlSession sqlSession1 = factory.openSession();
        UserDao userDao1 = sqlSession1.getMapper(UserDao.class);
        User user1 = userDao1.findById(41);
        System.out.println(user1);
        sqlSession1.close();//一级缓存消失

        SqlSession sqlSession2 = factory.openSession();
        UserDao userDao2 = sqlSession2.getMapper(UserDao.class);
        User user2 = userDao2.findById(41);
        System.out.println(user2);
        sqlSession2.close();

        System.out.println(user1 == user2);
    }
}

来源：CSDN

作者：qq_187352634

链接：https://blog.csdn.net/qq_37755459/article/details/104427321