Spring整合Mybatis也就是在Mybatis上不用再new对象了，把Mybatis的一些东西交给了Spring管理，既然是Spring管理，那就少不了类和对象，这里以一个查询语句来进行讲解
其基本机构如下
先给出pom.xml
<?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">
<parent>
<artifactId>springstudy</artifactId>
<groupId>org.example</groupId>
<version>1.0-SNAPSHOT</version>
</parent>
<modelVersion>4.0.0</modelVersion>
<artifactId>spring10mybatis</artifactId>
<dependencies>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.12</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-webmvc</artifactId>
<version>5.2.0.RELEASE</version>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>8.0.17</version>
</dependency>
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis</artifactId>
<version>3.5.2</version>
</dependency>
<!--Spring操作数据库需要一个spring-jdbc-->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-jdbc</artifactId>
<version>5.2.0.RELEASE</version>
</dependency>
<!--AOP置入包-->
<dependency>
<groupId>org.aspectj</groupId>
<artifactId>aspectjweaver</artifactId>
<version>1.8.13</version>
</dependency>
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis-spring</artifactId>
<version>2.0.2</version>
</dependency>
</dependencies>
</project>
首先就是一个实体类了，对应数据库中的表
package com.zhiying.pojo;
public class User {
private int id;
private String username;
private String password;
public User() {
}
public User(int id, String username, String password) {
this.id = id;
this.username = username;
this.password = password;
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
@Override
public String toString() {
return "User{" +
"id=" + id +
", username='" + username + '\'' +
", password='" + password + '\'' +
'}';
}
}
然后是一个查询语句的接口
package com.zhiying.mapper;
import com.zhiying.pojo.User;
import java.util.List;
public interface UserMapper {
List<User> getUserList();
}
由于要整合到Spring，所以需要该接口的实现类，并写一个set方法，使用set进行注入
package com.zhiying.mapper;
import com.zhiying.pojo.User;
import org.mybatis.spring.SqlSessionTemplate;
import java.util.List;
public class UserMapperImpl implements UserMapper {
private SqlSessionTemplate sqlSessionTemplate;
public void setSqlSessionTemplate(SqlSessionTemplate sqlSessionTemplate) {
this.sqlSessionTemplate = sqlSessionTemplate;
}
public List<User> getUserList() {
UserMapper mapper = sqlSessionTemplate.getMapper(UserMapper.class);
return mapper.getUserList();
}
}
到这里就该写一些配置文件了，首先是对该查询语句的配置文件
<?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.zhiying.mapper.UserMapper">
<select id="getUserList" resultType="com.zhiying.pojo.User">
select * from user
</select>
</mapper>
然后是mybatis的配置文件，这里在单独使用mybatis时有连接数据库的配置，这里整合到了Spring中，所以这里只剩下把刚刚的查询配置文件加载到mybatis配置文件中
<?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>
<mappers>
<mapper resource="UserMapper.xml"/>
</mappers>
</configuration>
最后就是Spring的配置了
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.springframework.org/schema/beans
https://www.springframework.org/schema/beans/spring-beans.xsd">
<!-- DataSource：使用Spring的数据源替换Mybatis的配置 c3p0 druid
这里使用Spring的JDBC org.springframework.jdbc.datasource
-->
<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?userSSL=false&useUnicode=true&characterEncoding=UTF-8&serverTimezone=UTC"/>
<property name="username" value="root"/>
<property name="password" value="root"/>
</bean>
<!-- sqlSessionFactory-->
<bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
<property name="dataSource" ref="dataSource" />
<property name="mapperLocations" value="UserMapper.xml"/>
</bean>
<!-- SqlSessionTemplate就是我们使用的sqlSession-->
<bean id="sqlSessionTemplate" class="org.mybatis.spring.SqlSessionTemplate">
<!-- 只能用构造器注入，因为sqlSessionFactory没有set方法-->
<constructor-arg name="sqlSessionFactory" ref="sqlSessionFactory"/>
</bean>
<bean id="userMapper" class="com.zhiying.mapper.UserMapperImpl">
<property name="sqlSessionTemplate" ref="sqlSessionTemplate"/>
</bean>
</beans>
接下来就是测试了
import com.zhiying.mapper.UserMapper;
import com.zhiying.pojo.User;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import java.io.IOException;
public class MyTest {
@Test
public void test() throws IOException {
ApplicationContext context = new ClassPathXmlApplicationContext("applicationContext.xml");
UserMapper userMapper = (UserMapper) context.getBean("userMapper");
for (User user : userMapper.getUserList()) {
System.out.println(user);
}
}
}