什么是 MyBatis-Spring?
MyBatis-Spring 会帮助你将 MyBatis 代码无缝地整合到 Spring 中。它将允许 MyBatis 参与到 Spring 的事务管理之中,创建映射器 mapper 和 SqlSession 并注入到 bean 中,以及将 Mybatis 的异常转换为 Spring 的 DataAccessException。 最终,可以做到应用代码不依赖于 MyBatis,Spring 或 MyBatis-Spring。
将spring与mybatis整合
- 导入maven依赖
<!-- mysql连接依赖-->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>8.0.22</version>
</dependency>
<!-- mybatis与spring整合依赖-->
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis-spring</artifactId>
<version>2.0.6</version>
</dependency>
<!--mybatis依赖-->
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis</artifactId>
<version>3.5.5</version>
</dependency>
<build>
<!-- 静态资源导出问题
目的是把src/main/java和src/main/resource目录中的xml文件和properties配置文件包含到输出结果中,
输出到classes目录中-->
<resources>
<resource>
<directory>src/main/java</directory><!--所在目录-->
<includes>
<include>**/*.properties</include>
<include>**/*.xml</include>
</includes>
<filtering>false</filtering>
</resource>
<resource>
<directory>src/main/resources</directory><!--所在目录-->
<includes>
<include>**/*.properties</include>
<include>**/*.xml</include>
</includes>
<filtering>false</filtering>
</resource>
</resources>
</build>
- 创建实体类
public class Book implements Serializable {
private int id;
private String name;
private Double price;
public Book(int id, String name, Double price) {
this.id = id;
this.name = name;
this.price = price;
}
public Book() {
}
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 Double getPrice() {
return price;
}
public void setPrice(Double price) {
this.price = price;
}
@Override
public String toString() {
return "Book{" +
"id=" + id +
", name='" + name + '\'' +
", price=" + price +
'}';
}
}
- 创建mapper接口类
public interface BookMapper {
List<Book> queryList();
}
- 使用mapper.xml编写sql语句
<?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">
<!--绑定mapper接口-->
<mapper namespace="com.chenhui.mapper.BookMapper">
<select id="queryList" resultType="book">
select * from book
</select>
</mapper>
- 配置spring核心配置文件并整合mybatis
<?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:aop="http://www.springframework.org/schema/aop"
xsi:schemaLocation="http://www.springframework.org/schema/beans
https://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/context
https://www.springframework.org/schema/context/spring-context.xsd
http://www.springframework.org/schema/aop
https://www.springframework.org/schema/aop/spring-aop.xsd">
<!-- 配置spring内置数据源Spring-JDBC-->
<bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
<property name="driverClassName" value="com.mysql.cj.jdbc.Driver"/>
<property name="url" value="jdbc:mysql://localhost:3306/mybatis_zr?serverTimezone=PRC"/>
<property name="username" value="root"/>
<property name="password" value="root"/>
</bean>
<!-- 配置SqlSessionFactory-->
<bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
<!-- 引用数据源-->
<property name="dataSource" ref="dataSource"/>
<!-- 绑定mybatis配置文件-->
<property name="configLocation" value="classpath:mybatis.xml"/>
<!-- 配置别名-->
<property name="typeAliases" value="com.chenhui.pojo.Book"/>
<!--配置SQL语句mapper.xml文件-->
<property name="mapperLocations" value="classpath:com/chenhui/mapper/*.xml"/>
</bean>
<!-- 配置SQLSession交给spring来管理-->
<bean id="sqlSession" class="org.mybatis.spring.SqlSessionTemplate">
<!-- 只能使用构造器注入sqlSessionFactory,因为它没有set方法注入-->
<constructor-arg name="sqlSessionFactory" ref="sqlSessionFactory"/>
</bean>
<!-- 注册接口的实现类,交给spring来管理,需要一个SqlSessionTemplate对象进行执行操作-->
<bean id="bookMapper" class="com.chenhui.mapper.BookMapperImpl">
<property name="sqlSession" ref="sqlSession"/>
</bean>
</beans>
- 编写接口实现类
public class BookMapperImpl implements BookMapper {
private SqlSessionTemplate sqlSession;
//通过set方法注入SqlSessionTemplate交给spring管理
public void setSqlSession(SqlSessionTemplate sqlSession) {
this.sqlSession = sqlSession;
}
//执行查询数据的方法
public List<Book> queryList() {
BookMapper mapper = sqlSession.getMapper(BookMapper.class);
return mapper.queryList();
}
}
- 测试:
public static void main(String[] args) {
//加载spring配置文件获取bean容器
ApplicationContext context=new ClassPathXmlApplicationContext("spring-dao.xml");
//获取bean对象
BookMapper bookMapper = context.getBean("bookMapper", BookMapper.class);
//执行方法
List<Book> books = bookMapper.queryList();
System.out.println(books);
}
结果:
方式二:使用SqlSessionDaoSupport替代SqlSessionTemplate
修改方式:
接口实现类
public class BookMapperImpl extends SqlSessionDaoSupport implements BookMapper {
//执行查询数据的方法
public List<Book> queryList() {
//直接通过父类SqlSessionDaoSupport的getSqlSession获取sqlSessionTemplate对象
BookMapper mapper = super.getSqlSession().getMapper(BookMapper.class);
return mapper.queryList();
}
}
spring核心配置文件整合mybatis
<?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:aop="http://www.springframework.org/schema/aop"
xsi:schemaLocation="http://www.springframework.org/schema/beans
https://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/context
https://www.springframework.org/schema/context/spring-context.xsd
http://www.springframework.org/schema/aop
https://www.springframework.org/schema/aop/spring-aop.xsd">
<!-- 配置spring内置数据源Spring-JDBC-->
<bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
<property name="driverClassName" value="com.mysql.cj.jdbc.Driver"/>
<property name="url" value="jdbc:mysql://localhost:3306/mybatis_zr?serverTimezone=PRC"/>
<property name="username" value="root"/>
<property name="password" value="root"/>
</bean>
<!-- 配置SqlSessionFactory-->
<bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
<!-- 引用数据源-->
<property name="dataSource" ref="dataSource"/>
<!-- 绑定mybatis配置文件-->
<property name="configLocation" value="classpath:mybatis.xml"/>
<!-- 配置别名-->
<property name="typeAliases" value="com.chenhui.pojo.Book"/>
<!--配置SQL语句mapper.xml文件-->
<property name="mapperLocations" value="classpath:com/chenhui/mapper/*.xml"/>
</bean>
<!-- 注册接口的实现类,交给spring来管理-->
<bean id="bookMapper" class="com.chenhui.mapper.BookMapperImpl">
<!--由于SqlSessionDaoSupport创建sqlSessionTemplate需要一个sqlSessionFactory对象,因此通过set方法注入-->
<property name="sqlSessionFactory" ref="sqlSessionFactory"/>
</bean>
</beans>
测试:
public static void main(String[] args) {
//加载spring配置文件获取bean容器
ApplicationContext context=new ClassPathXmlApplicationContext("spring-dao.xml");
//获取bean对象
BookMapper bookMapper = context.getBean("bookMapper", BookMapper.class);
//执行方法
List<Book> books = bookMapper.queryList();
System.out.println(books);
}
结果: