Spring 与 MyBatis 框架集成

Spring 集成 MyBatis

为何要框架集成

Spring 通过 IoC 和 AoP 两大法宝，可以简化 MyBatis 框架配置和代码开发。

框架集成步骤

第①步：创建数据库表

SET NAMES utf8mb4;
SET FOREIGN_KEY_CHECKS = 0;

-- ----------------------------
-- Table structure for tb_user
-- ----------------------------
DROP TABLE IF EXISTS `tb_user`;
CREATE TABLE `tb_user`  (
  `id` int(0) NOT NULL AUTO_INCREMENT,
  `name` varchar(255) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL,
  PRIMARY KEY (`id`) USING BTREE
) ENGINE = InnoDB CHARACTER SET = utf8 COLLATE = utf8_general_ci ROW_FORMAT = Dynamic;

SET FOREIGN_KEY_CHECKS = 1;

tb_user 表非常简单，只有一个主键 id 和一个字段name

第②步：IDEA 创建 Maven 项目

第③步：修改 pom.xml 配置添加 Maven 依赖包

<?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>org.example</groupId>
    <artifactId>springmybatisdemo</artifactId>
    <version>1.0-SNAPSHOT</version>

    <properties>
        <maven.compiler.source>8</maven.compiler.source>
        <maven.compiler.target>8</maven.compiler.target>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <!-- Spring版本 -->   
        <spring.version>5.2.3.RELEASE</spring.version>
    </properties>

    <dependencies>
        <!-- Spring依赖 -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>${spring.version}</version>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-core</artifactId>
            <version>${spring.version}</version>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-jdbc</artifactId>
            <version>${spring.version}</version>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-tx</artifactId>
            <version>${spring.version}</version>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-aop</artifactId>
            <version>${spring.version}</version>
        </dependency>


        <!-- MyBatis依赖 -->
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.5.5</version>
        </dependency>
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis-spring</artifactId>
            <version>2.0.5</version>
        </dependency>

        <!-- 数据库驱动依赖（根据你使用的数据库选择） -->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.18</version>
        </dependency>

        <!-- lombok 依赖-->
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.16.18</version>
        </dependency>
        
        <!-- 日志整合 slf4j门面设计模式与 log4j或log4j2一起使用-->
        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>slf4j-log4j12</artifactId>
            <version>1.7.36</version>
        </dependency>
        <!-- 日志-->
        <dependency>
            <groupId>log4j</groupId>
            <artifactId>log4j</artifactId>
            <version>1.2.17</version>
        </dependency>
    </dependencies>
</project>

第④步：创建 UserEntity 实体类

创建 entity 或 domain 包，并在包中创建 UserEntity 实体类，如下：

package com.binge.entity;

import lombok.*;

@Data
@AllArgsConstructor
public class UserEntity {
    private Long id;
    private String name;
}

第⑤步：创建 UserMapper 接口

创建 dao 包，并在包中创建 UserMapper 接口，如下：

package com.binge.dao;

import com.binge.entity.UserEntity;
import org.apache.ibatis.annotations.Mapper;

import java.util.List;

public interface UserMapper {
    void insert(UserEntity userEntity);
    List<UserEntity> getList();
}

该接口提供了插入和查询数据库两个方法

第⑥步：创建 UserMapper 接口对应的 UserMapper.xml 映射文件

在 resources 下创建 mapper 文件夹，用于存放映射文件，然后创建 UserMapper.xml 映射文件，如下：

<?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.binge.dao.UserMapper">
    <insert id="insert" parameterType="com.binge.entity.UserEntity" keyProperty="id" useGeneratedKeys="true">
        <![CDATA[ INSERT INTO `tb_user` (name) VALUES (#{name})]]>
    </insert>

    <select id="getList" resultType="com.binge.entity.UserEntity">
        <![CDATA[
        SELECT id,name FROM tb_user
        ]]>
    </select>
</mapper>

第⑦步：创建 IUserService 接口和 UserServiceImpl 实现类

创建 Service 包，并在包中创建 IUserService 接口，如下：

package com.binge.service;

import com.binge.entity.UserEntity;
import java.util.List;

public interface IUserService {
    UserEntity insert(UserEntity userModel);
    List<UserEntity> getList();
}

在 Service 包内创建 impl 包，用于存放 UserServiceImpl 实现类，如下：

package com.binge.service.impl; 

import com.binge.entity.UserEntity;
import com.binge.dao.UserMapper;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Propagation;
import org.springframework.transaction.annotation.Transactional;
import com.binge.service.IUserService;

import java.util.List;

@Service
public class UserServiceImpl implements IUserService {
    @Autowired
    private UserMapper userMapper;

    @Transactional(rollbackFor = Exception.class)
    @Override
    public UserEntity insert(UserEntity userModel) {
        userMapper.insert(userModel);
        return userModel;
    }

    @Transactional(propagation = Propagation.SUPPORTS, readOnly = true)
    @Override
    public List<UserEntity> getList() {
        return userMapper.getList();
    }
}

第⑧步：创建数据库配置文件 database.properties

在 resources 文件夹下创建 database.properties 文件，如下：

spring.datasource.url=jdbc:mysql://localhost:3306/binge?characterEncoding=utf8&serverTimezone=UTC
spring.datasource.username=root
spring.datasource.password=123456
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver

注意：需要根据自己电脑的数据库信息修改以上配置

第⑨步：创建 Spring IoC 容器 spring-config.xml 配置文件

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:context="http://www.springframework.org/schema/context"
       xmlns:mybatis="http://mybatis.org/schema/mybatis-spring"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
           http://www.springframework.org/schema/beans/spring-beans.xsd
           http://www.springframework.org/schema/context
           http://www.springframework.org/schema/context/spring-context.xsd
           http://mybatis.org/schema/mybatis-spring
           http://mybatis.org/schema/mybatis-spring.xsd">

    <!-- 自动扫描注解 -->
    <context:component-scan base-package="com.binge"/>

    <!-- 引入数据库配置文件-->
    <context:property-placeholder location="classpath:database.properties"/>

    <!-- 配置数据源 -->
    <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
        <property name="driverClassName" value="${spring.datasource.driver-class-name}"/>
        <property name="url" value="${spring.datasource.url}"/>
        <property name="username" value="${spring.datasource.username}"/>
        <property name="password" value="${spring.datasource.password}"/>
    </bean>

    <!-- MyBatis 扫描 mapper -->
    <mybatis:scan base-package="com.binge.dao"/>

    <!-- 配置SqlSessionFactory -->
    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="dataSource" ref="dataSource"/>
        <!--设置entity实体类路径-->
        <property name="typeAliasesPackage" value="com.binge.entity" />
        <!--设置mapper映射文件路径-->
        <property name="mapperLocations" value="classpath*:mapper/*.xml" />
    </bean>
</beans>

在 resources 文件夹下创建日志配置文件 log4j.properties，如下：

log4j.rootLogger=DEBUG, stdout
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%5p [%t] - %m%n

第⑩步：创建 SpringMyBatisTest 测试类

import com.binge.entity.UserEntity;
import com.binge.service.IUserService;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import java.util.List;

public class SpringMybatisTest {
    public static void main(String[] args) {
        ApplicationContext context = new ClassPathXmlApplicationContext("spring-config.xml");

        IUserService userService = context.getBean(IUserService.class);
        List<UserEntity> users = userService.getList();

        System.out.println(users);

        UserEntity  userEntity = userService.insert(new UserEntity(null, "张三"));
        System.out.println(userEntity);
    }
}

运行测试类，结果如下：

[UserEntity(id=2, name=spring系列), UserEntity(id=3, name=spring系列), UserEntity(id=4, name=刘德华), UserEntity(id=5, name=郭富城), UserEntity(id=6, name=张学友), UserEntity(id=7, name=黎明), UserEntity(id=8, name=刘德华), UserEntity(id=9, name=郭富城), UserEntity(id=10, name=张学友), UserEntity(id=11, name=黎明), UserEntity(id=12, name=张三), UserEntity(id=13, name=张三), UserEntity(id=14, name=张三)]
UserEntity(id=15, name=张三)

Process finished with exit code 0

结果显示插入和查询数据，至此框架集成成功：）