spring学习日记-day7-整合mybatis

一、学习目标

        spring整合MyBatis的原理主要涉及到将MyBatis的Mapper映射文件交由Spring容器管理，并将其注入到MyBatis的SqlSessionFactory中，从而实现两者的整合。

二、整合mybatis

1.写一个mybatis测试案例

项目结构：

1.数据库

CREATE DATABASE `mybatis`;
USE `mybatis`;create table Users(id int not null auto_increment primary key,name varchar(10) not null,age int not null
);insert into Users(id,name,age) values(null,'张三',20),(null,'李四',18);

2.实体类

public class User {private int id;  //idprivate String name;   //姓名private int age;   //密码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 int getAge() {return age;}public void setAge(int age) {this.age = age;}public User(int id, String name, int age) {this.id = id;this.name = name;this.age = age;}@Overridepublic String toString() {return "User{" +"id=" + id +", name='" + name + '\'' +", age=" + age +'}';}public User() {}
}

2.编写接口

public interface UserMapper {public List<User> selectUser();
}

3.mybatisConfig配置文件

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configurationPUBLIC "-//mybatis.org//DTD Config 3.0//EN""http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration><typeAliases><package name="com.lzh.pojo"/></typeAliases><environments default="development"><environment id="development"><transactionManager type="JDBC"/><dataSource type="POOLED"><property name="driver" value="com.mysql.jdbc.Driver"/><property name="url" value="jdbc:mysql://localhost:3306/mybatis?useSSL=true&amp;useUnicode=true&amp;characterEncoding=utf8&amp;useSSL=false"/><property name="username" value="root"/><property name="password" value="admin123"/></dataSource></environment></environments><mappers><package name="com.lzh.dao"/></mappers>
</configuration>

4.UserrMapper文件：

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapperPUBLIC "-//mybatis.org//DTD Mapper 3.0//EN""http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.lzh.dao.UserMapper"><select id="selectUser" resultType="User">select * from users</select>
</mapper>

5.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"><modelVersion>4.0.0</modelVersion><groupId>com.lzh</groupId><artifactId>spring-07</artifactId><version>1.0-SNAPSHOT</version><dependencies><dependency><groupId>junit</groupId><artifactId>junit</artifactId><version>4.12</version></dependency><dependency><groupId>org.mybatis</groupId><artifactId>mybatis</artifactId><version>3.5.2</version></dependency><dependency><groupId>mysql</groupId><artifactId>mysql-connector-java</artifactId><version>5.1.47</version></dependency><dependency><groupId>org.springframework</groupId><artifactId>spring-webmvc</artifactId><version>5.1.10.RELEASE</version></dependency><dependency><groupId>org.springframework</groupId><artifactId>spring-jdbc</artifactId><version>5.1.10.RELEASE</version></dependency><!-- https://mvnrepository.com/artifact/org.aspectj/aspectjweaver --><dependency><groupId>org.aspectj</groupId><artifactId>aspectjweaver</artifactId><version>1.9.4</version></dependency><dependency><groupId>org.mybatis</groupId><artifactId>mybatis-spring</artifactId><version>2.0.2</version></dependency></dependencies><build><resources><resource><directory>src/main/java</directory><includes><include>**/*.properties</include><include>**/*.xml</include></includes><filtering>true</filtering></resource></resources></build><properties><maven.compiler.source>1.8</maven.compiler.source><maven.compiler.target>1.8</maven.compiler.target></properties></project>

6.测试

@Testpublic void selectUser() throws IOException {String resource = "MybatisConfig.xml";InputStream inputStream = Resources.getResourceAsStream(resource);SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);SqlSession sqlSession = sqlSessionFactory.openSession();UserMapper mapper = sqlSession.getMapper(UserMapper.class);List<User> userList = mapper.selectUser();for (User user: userList){System.out.println(user);}sqlSession.close();}

2.整合mybatis方式一

1.配置数据源

    <!--配置数据源->定义一个数据源bean，id为"dataSource"，用于管理数据库连接。class属性指定了数据源的实现类为org.springframework.jdbc.datasource.DriverManagerDataSource，--><bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource"><property name="driverClassName" value="com.mysql.jdbc.Driver"/><!--设置数据库连接的URL。- useSSL=true&amp;useSSL=false：这里似乎有一个错误，通常只需要一个useSSL参数，并且应该保持一致。对于本地开发，通常不需要SSL，所以应设置为false。- useUnicode=true：指定使用Unicode字符集。- characterEncoding=utf8：指定字符编码为UTF-8。注意，从MySQL 5.5.3版本开始，建议使用utf8mb4代替utf8，以支持更广泛的Unicode字符，包括emoji表情等。--><property name="url" value="jdbc:mysql://localhost:3306/mybatis?useSSL=false&amp;useUnicode=true&amp;characterEncoding=utf8"/><property name="username" value="root"/><property name="password" value="admin123"/></bean>

2.配置SqlSessionFactory，关联MyBatis注册,sqlSessionTemplate，关联sqlSessionFactory

     <!-- 配置SqlSessionFactory --><bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean"><!-- 注入数据源，这里的ref指向之前定义的数据源bean --><property name="dataSource" ref="dataSource"/><!-- 关联Mybatis的全局配置文件，MybatisConfig.xml中包含了MyBatis的设置，如别名、类型处理器、插件等 --><property name="configLocation" value="classpath:MybatisConfig.xml"/><!-- 指定Mapper XML文件的位置，MyBatis会根据这些XML文件来创建Mapper接口的实现 --><!-- 注意：这里只指定了一个Mapper XML文件，如果有多个，可以使用逗号分隔或者使用通配符 --><property name="mapperLocations" value="classpath:com/lzh/dao/UserMapper.xml"/></bean><!-- 注册sqlSessionTemplate，关联sqlSessionFactory --><bean id="sqlSession" class="org.mybatis.spring.SqlSessionTemplate"><!-- 通过构造器注入SqlSessionFactory，使得SqlSessionTemplate能够管理SqlSession --><!-- index="0"指定了构造器参数的索引，这里假设SqlSessionTemplate的构造器第一个参数就是SqlSessionFactory --><constructor-arg index="0" ref="sqlSessionFactory"/></bean>

3.增加接口实现类

public class UserDaoImpl implements UserMapper {// 注入SqlSessionTemplate，Spring容器会负责注入private SqlSessionTemplate sqlSession;// 通过构造器注入SqlSessionTemplate（推荐的方式，因为它支持Spring的依赖注入最佳实践）public void setSqlSession(SqlSessionTemplate sqlSession) {this.sqlSession = sqlSession;}public List<User> selectUser() {UserMapper mapper = sqlSession.getMapper(UserMapper.class);return mapper.selectUser();}
}

4.注册bean

    <bean id="userDao" class="com.lzh.dao.UserDaoImpl"><property name="sqlSession" ref="sqlSession"/></bean>

5.修改mybatis配置文件

     <!--mappers><package name="com.lzh.dao"/></mappers-->

6.测试

@Testpublic void test2(){ApplicationContext context = new ClassPathXmlApplicationContext("beans.xml");UserMapper mapper = (UserMapper) context.getBean("userDao");List<User> user = mapper.selectUser();System.out.println(user);}

2.整合mybatis方式二

1.修改接口实现类

public class UserDaoImpl extends SqlSessionDaoSupport implements UserMapper {public List<User> selectUser() {UserMapper mapper = getSqlSession().getMapper(UserMapper.class);return mapper.selectUser();}
}

2.修改bean配置

 <!-- 注册sqlSessionTemplate，关联sqlSessionFactory --><!--bean id="sqlSession" class="org.mybatis.spring.SqlSessionTemplate">< 通过构造器注入SqlSessionFactory，使得SqlSessionTemplate能够管理SqlSession --><!-- index="0"指定了构造器参数的索引，这里假设SqlSessionTemplate的构造器第一个参数就是SqlSessionFactory --><!--constructor-arg index="0" ref="sqlSessionFactory"/></bean--><!--bean id="userDao" class="com.lzh.dao.UserDaoImpl"><property name="sqlSession" ref="sqlSession"/></bean--><bean id="userDao" class="com.lzh.dao.UserDaoImpl"><property name="sqlSessionFactory" ref="sqlSessionFactory" /></bean>