MyBatis-Spring 入门

🏷️ MyBatis

官方的文档里写的太简单了，这里是根据文档创建的示例程序。

使用 MyBatis-Spring 访问 SqlServer 数据库。

1. pom.xml 添加依赖

<?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>liujiajia.me.learning.mybatis</groupId>
    <artifactId>learning-mybatis</artifactId>
    <version>1.0-SNAPSHOT</version>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.1.2.RELEASE</version>
    </parent>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>2.0.0</version>
        </dependency>
        <dependency>
            <groupId>com.microsoft.sqlserver</groupId>
            <artifactId>mssql-jdbc</artifactId>
        </dependency>
    </dependencies>
</project>

2. 在 resources 目录中创建 applicationContext.xml 配置文件

配置 SqlSessionFactory 、 DataSource 和 Mapper 。

<?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
        http://www.springframework.org/schema/beans/spring-beans.xsd">
    <!--Sql Session Factory-->
    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="dataSource" ref="dataSource" />
    </bean>
    <!--数据源-->
    <bean id="dataSource"
        class="org.springframework.jdbc.datasource.DriverManagerDataSource">
        <property name="driverClassName" value="com.microsoft.sqlserver.jdbc.SQLServerDriver" />
        <property name="url" value="jdbc:sqlserver://192.168.0.1:1433;databaseName=TEST" />
        <property name="username" value="username" />
        <property name="password" value="password" />
    </bean>
    <!--Mapper-->
    <bean id="userMapper" class="org.mybatis.spring.mapper.MapperFactoryBean">
        <property name="mapperInterface" value="liujiajia.me.learning.mybatis.UserMapper" />
        <property name="sqlSessionFactory" ref="sqlSessionFactory" />
    </bean>
</beans>

3. Application.java

创建程序入口，并导入配置文件。

package liujiajia.me.learning.mybatis;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.ImportResource;

/**
* Created by liujiajia on 2019/1/23.
*/
@SpringBootApplication
@ImportResource("classpath:applicationContext.xml")
public class Application {
    public static void main(String[] args) {
        SpringApplication.run(Application.class, args);
    }
}

4. UserMapper.java

表模型 User 根据自己的需要创建。

package liujiajia.me.learning.mybatis;

import org.apache.ibatis.annotations.Param;
import org.apache.ibatis.annotations.Select;

/**
* Created by liujiajia on 2019/1/23.
*/
public interface UserMapper {
    @Select("SELECT * FROM User WHERE Account = #{account}")
    User getUser(@Param("account") String account);
}

5. UserController.java

package liujiajia.me.learning.mybatis;

import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RestController;

import javax.annotation.Resource;

/**
* Created by liujiajia on 2019/1/23.
*/
@RestController
@RequestMapping("api/user")
public class UserController {
    @Resource
    private UserMapper userMapper;

    @RequestMapping(value = "{account}", method = RequestMethod.GET)
    public User getUser(@PathVariable("account") String account) {
        return userMapper.getUser(account);
    }
}

6. 启动应用

启动 Application，然后访问 http://localhost:8080/api/user/account 查看是否能获取到数据。

SpringBoot 默认使用 8080 端口。

如需修改可通过启动参数 --server.port=8080 来自定义端口号。
或者通过在 resources 目录下创建 applicaton.yml 配置文件并设置如下内容来自定义端口号。

server:
    port: 8083

参数和 applicaton.yml 配置文件同时使用时，参数的优先级较高。