Spring整合Mybatis注解方式

大家好，又见面了，我是你们的朋友全栈君。

Spring整合Mybatis（注解方式）

目录

• Spring整合Mybatis（注解方式）
  • 环境准备
  • 纯注解方式
  • 配置类具体内容
  • 测试类具体内容

环境准备

jar包：

• Spring所需依赖：spring-context、spring-aspects、aspectjrt、aspectjweaver、spring-tx、spring-jdbc
• mybatis所需要：mybatis、mybatis-spring、mysql-connector-java、(druid、c3p0、HikariCP)
• 辅助性依赖：logback-classic、lombok、spring-test、junit、mapper(可选)、pagehelper(可选)

数据库：mysql

服务层代码

@Service
@Data
public class UserService implements IUserService { 
   

    private SqlSessionTemplate sqlSession;
    private UserMapper mapper;

    public UserService(SqlSessionTemplate sqlSession){ 
   
        this.sqlSession=sqlSession;
        mapper=sqlSession.getMapper(UserMapper.class);
    }

    @Override
    public List<User> getAll() { 
   
        return mapper.getAll();
    }
}

mapper.xml

<?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.hello.mapper.UserMapper">

    <select id="getAll" resultType="user">
        select * from user
    </select>

</mapper>

纯注解方式
纯注解方式需要一个配置类来代替xml配置文件的作用，需在配置文件上注

//注解扫描
@ComponentScan(basePackages = "com.hello")
//声明当前类为配置类
@Configuration

配置类中@Bean相当于xml的标签
通过@Bean将类放入spring容器，也可以通过注解扫描

配置类具体内容

@ComponentScan(basePackages = "com.hello")
@Configuration
public class Config { 

//配置数据库连接池
@Bean
public DataSource dataSource(){ 

//使用HikariCP连接池
HikariDataSource hikariDataSource = new HikariDataSource();
//配置连接池的jdbcUrl属性
hikariDataSource.setJdbcUrl("jdbc:mysql://localhost:3306/ssm?servexrTimezone=GMT%2B8");
//账号
hikariDataSource.setUsername("root");
//密码
hikariDataSource.setPassword("root");
//驱动Driver
hikariDataSource.setDriverClassName("com.mysql.jdbc.Driver");
return hikariDataSource;
}
//配置sqlSessionFactory
@Bean
public SqlSessionFactory sqlSessionFactoryBean() throws Exception { 

//在spring和Mybatis整合中采用mybatis提供的SQLSessionFactoryBean对象
SqlSessionFactoryBean sqlSessionFactoryBean = new SqlSessionFactoryBean();
//为sqlSessionFatoryBean设置连接池属性
sqlSessionFactoryBean.setDataSource(dataSource());
//获取PathMatchingResourcePatternResolver对象为扫描mapper文件做准备
PathMatchingResourcePatternResolver path = new PathMatchingResourcePatternResolver();
//设置mapper文件位置 
sqlSessionFactoryBean.setMapperLocations(path.getResources("classpath*:com/hello/mapper/**/*.xml"));
//为javaBean对象设置别名
sqlSessionFactoryBean.setTypeAliasesPackage("com.hello.bean");
//返回SqlSessionFactory对象
return  sqlSessionFactoryBean.getObject();
}
//配置sqlSession
@Bean
public SqlSessionTemplate sqlSessionTemplate() throws Exception { 

//将SqlSessionFactory作为参数传入构造方法
SqlSessionTemplate sqlSessionTemplate = new SqlSessionTemplate(sqlSessionFactoryBean());
return sqlSessionTemplate;
}
@Bean
public UserService userService() throws Exception { 

UserService userService = new UserService(sqlSessionTemplate());
return userService;
}
}

测试类具体内容

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(classes = { 
Config.class})
public class AppTest 
{ 

@Autowired
public UserService userService;
@Test
public void getALL(){ 

List<User> users = userService.getAll();
for (User user:users) { 

System.out.println(user);
}
}
}