Spring集成Mybatis过程详细讲解

2023-03-19 17:03:44 过程 集成 讲解

为啥学习集成Mybatis ORM框架

虽然spring中提供了JDBCTemplate模块,已经很大程度了解决了JDBC代码的复杂度,但它仍然是和Java代码写在一起的。反观 Mybatis 将 sql 语句写在配置文件中,使得SQL语句和程序实现了松耦合。而且提供了些许标签,使得SQL可以是动态的。在ORM基础上想要更好的用Spring的DI、aop事务处理、Junit支持等实现成果,学会使用 Spring 框架集成 Mybatis 是大势所趋。

实现步骤

第一步:准备数据库

第二步:idea中创建一个模块,并引入以下依赖

  • spring-context
  • spring-jdbc
  • Mysql驱动
  • mybatis
  • mybatis-spring:mybatis提供的与spring框架集成的依赖
  • druid:德鲁伊连接池
  • junit
    <dependencies>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>6.0.5</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-jdbc</artifactId>
            <version>6.0.5</version>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.31</version>
        </dependency>
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.5.11</version>
        </dependency>
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis-spring</artifactId>
            <version>3.0.1</version>
        </dependency>
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid</artifactId>
            <version>1.2.16</version>
        </dependency>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.13</version>
            <scope>test</scope>
        </dependency>
    </dependencies>

第三步:基于三层架构实现,所以提前创建好所有的包

  • XXXX.mapper
  • XXXX.service
  • XXXX.service.impl
  • XXXX.bean

第四步:编写bean

Account,按bean规范创建

第五步:编写Mapper接口

AccountMapper接口,定义与数据库交互的方法

package com.ncpowernode.spring.mappers;
import com.ncpowernode.spring.bean.Account;
import java.util.List;
public interface AccountMapper {
    List<Account> selectAll();
    Account selectByActno(String actno);
    int insert(Account account);
    int deleteByActno(String actno);
    int update(Account account);
}

第六步:编写mapper配置文件

<?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.ncpowernode.spring.mappers.AccountMapper">
    <select id="selectAll" resultType="account">
        select * from t_act;
    </select>
    <insert id="insert">
        insert into t_act values(#{actno},#{balance})
    </insert>
    <delete id="deleteByActno">
        delete from t_act where actno = #{actno};
    </delete>
    <select id="selectByActno" resultType="account">
        select * from t_act where actno = #{actno};
    </select>
    <update id="update">
        update t_act set balance = #{balance} where actno = #{actno};
    </update>
</mapper>

第七步:编写service接口和service接口的实现类

service接口

package com.ncpowernode.spring.service;
import com.ncpowernode.spring.bean.Account;
import java.util.List;
public interface AccountService {
    int save(Account act);
    int deleteByActno(String actno);
    List<Account> getAll();
    void transfer(String froMactno,String toActno,double money);
}

service实现

package com.ncpowernode.spring.service.impl;
import com.ncpowernode.spring.bean.Account;
import com.ncpowernode.spring.mappers.AccountMapper;
import com.ncpowernode.spring.service.AccountService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import java.util.List;
@Service("accountService")
@Transactional
public class AccountServiceImpl implements AccountService {
    @Autowired
    @Qualifier("accountMapper")
    private AccountMapper accountMapper;
    @Override
    public int save(Account act) {
        return accountMapper.insert(act);
    }
    @Override
    public int deleteByActno(String actno) {
        return accountMapper.deleteByActno(actno);
    }
    @Override
    public List<Account> getAll() {
        return accountMapper.selectAll();
    }
    @Override
    public void transfer(String fromActno, String toActno, double money) {
        // 判断余额
        Account fromAccount = accountMapper.selectByActno(fromActno);
        if (fromAccount.getBalance()<money) throw new RuntimeException("余额不足");
        // 更新数据库
        Account toAccount = accountMapper.selectByActno(toActno);
        fromAccount.setBalance(fromAccount.getBalance()-money);
        toAccount.setBalance(toAccount.getBalance()+money);
        int cnt = accountMapper.update(fromAccount);
        cnt += accountMapper.update(toAccount);
        // 判断业务是否实现成功
        if(cnt!=2) throw new RuntimeException("转账失败");
    }
}

第八步:编写jdbc.properties配置文件

数据库连接池相关信息

jdbc.driver=com.mysql.cj.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/???
jdbc.username=???
jdbc.passWord=???

第九步:编写mybatis-config.xml核心配置文件

<?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>
    <settings>
        <!--驼峰命名自动映射,默认false-->
        <setting name="mapUnderscoreToCamelCase" value="false"/>
        <!--设置懒加载-->
        <setting name="lazyLoadingEnabled" value="true"/>
        <!--配置日志,可以帮助我们查看sql执行信息-->
        <setting name="logImpl" value="STDOUT_LOGGING"/>
    </settings>
</configuration>

第十步:编写spring.xml配置文件

组件扫描

引入外部的属性文件

数据源

SqlSessionFactoryBean配置(注入mybatis核心配置文件路径,指明别名包,注入数据源)

Mapper扫描配置器(指定扫描的包)

事务管理器(DataSourceTransactionManager,注入数据源)

启动事务注解(注入事务管理器)

<?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:tx="http://www.springframework.org/schema/tx"
       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://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd">
    <!--组件扫描-->
    <context:component-scan base-package="com.ncpowernode.spring.service"/>
    <!--引入外部的属性文件-->
    <context:property-placeholder location="jdbc.properties"/>
    <!--数据源-->
    <bean id="dataSource" class="com.alibaba.druid.pool.DruidDataSource">
        <property name="driverClassName" value="${jdbc.driver}"/>
        <property name="url" value="${jdbc.url}"/>
        <property name="username" value="${jdbc.username}"/>
        <property name="password" value="${jdbc.password}"/>
    </bean>
    <!--配置SqlSessionFactoryBean-->
    <bean class="org.mybatis.spring.SqlSessionFactoryBean">
        <!--注入数据源-->
        <property name="dataSource" ref="dataSource"/>
        <!--指定别名包-->
        <property name="typeAliasesPackage" value="com.ncpowernode.spring.bean"/>
        <!--指定mybatis核心配置文件-->
        <property name="configLocation" value="mybatis-config.xml"/>
    </bean>
    <!--配置Mapper扫描配置器-->
    <!--主要扫描mapper接口,生成代理类-->
    <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
        <property name="basePackage" value="com.ncpowernode.spring.mappers"/>
    </bean>
    <!--事务管理器-->
    <bean id="txManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
        <property name="dataSource" ref="dataSource"/>
    </bean>
    <!--启动事务注解-->
    <tx:annotation-driven transaction-manager="txManager"/>
</beans>

第十一步:编写测试程序,并添加事务,进行测试。

	@Test
    public void testSM(){
        ApplicationContext applicationContext = new ClassPathXmlApplicationContext("spring.xml");
        AccountService accountService = applicationContext.getBean("accountService", AccountServiceImpl.class);
        accountService.getAll().forEach(System.out::println);
        accountService.transfer("act-001","act-002",10000.0);
    }

测试结果

到此这篇关于Spring集成Mybatis过程详细讲解的文章就介绍到这了,更多相关Spring集成Mybatis内容请搜索以前的文章或继续浏览下面的相关文章希望大家以后多多支持!

相关文章