Spring Boot Mybatis 整合
一、完整的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.example</groupId>
<artifactId>test</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging>
<name>test</name>
<description>Demo project for Spring Boot</description>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.5.2.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
<java.version>1.8</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<!-- mysql连接 -->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<scope>runtime</scope>
</dependency>
<!-- mybatis -->
<dependency>
<groupId>org.mybatis.spring.boot</groupId>
<artifactId>mybatis-spring-boot-starter</artifactId>
<version>1.1.1</version>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>
比较关键的是：mysql-connector-java、mybatis-spring-boot-starter，其它的根据使用引用。
二、启动文件 TestApplication.Java
package com.example;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.tomcat.jdbc.pool.DataSource;
import org.mybatis.spring.SqlSessionFactoryBean;
import org.mybatis.spring.annotation.MapperScan;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.core.io.support.PathMatchingResourcePatternResolver;
import org.springframework.jdbc.datasource.DataSourceTransactionManager;
import org.springframework.transaction.PlatformTransactionManager;
@SpringBootApplication
@MapperScan("com.example.mapper")
public class TestApplication {
private static Logger logger = LoggerFactory.getLogger(TestApplication.class);
@Bean
@ConfigurationProperties(prefix = "spring.datasource")
public DataSource dataSource() {
return new org.apache.tomcat.jdbc.pool.DataSource();
}
@Bean
public SqlSessionFactory sqlSessionFactoryBean() throws Exception {
SqlSessionFactoryBean sqlSessionFactoryBean = new SqlSessionFactoryBean();
sqlSessionFactoryBean.setDataSource(dataSource());
PathMatchingResourcePatternResolver resolver = new PathMatchingResourcePatternResolver();
sqlSessionFactoryBean.setMapperLocations(resolver.getResources("classpath:/mybatis/*.xml"));
return sqlSessionFactoryBean.getObject();
}
@Bean
public PlatformTransactionManager transactionManager() {
return new DataSourceTransactionManager(dataSource());
}
public static void main(String[] args) {
SpringApplication.run(TestApplication.class, args);
logger.info("SpringBoot Start Success");
}
}
类上边添加两个
- @Configuration注解（该注解类似于spring的配置文件）
- @MapperScan注解，指定扫描的mapper接口所在的包
注意3点：
-
在类上声明MapperScan，这是mybatis-spring-boot-starter在1.1.1引入的类Mapper，从而在mapper接口上不需要任何声明
-
配置dataSource、SqlSessionFactory、PlatformTransactionManager，其实默认的都已经配好，这里主要是为了标明Mapper的xml文件存在位置
-
src/main/resources下的文件，在打包之后，都在工程的根目录。
这个只需要更改两个地方：
-
MapperScan之后的"com.example.mapper"，改成Mapper接口文件所在的包名
-
sqlSessionFactoryBean方法中"classpath:/mybatis/*.xml"，改成Mapper的xml文件存在位置
三、启动配置文件 application.properties
spring.datasource.url=jdbc:mysql://localhost:3306/mytestdb?useUnicode=true&characterEncoding=UTF-8
spring.datasource.username=root
spring.datasource.password=123456
spring.datasource.driver-class-name=com.mysql.jdbc.Driver
spring.datasource.max-active=10
spring.datasource.max-idle=5
spring.datasource.min-idle=0
这个根据数据库情况配置
四、创建表，添加数据
CREATE TABLE `test_user` (
`id` bigint(20) NOT NULL AUTO_INCREMENT,
`name` varchar(100) NOT NULL,
`age` tinyint(4) NOT NULL,
PRIMARY KEY (`id`)
)
INSERT INTO `test_user` VALUES (1, '张三', 18);
五、model
package com.example.dto;
public class User {
public Long id;
public String name;
private int age;
public Long getId() {
return id;
}
public void setId(Long 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;
}
@Override
public String toString() {
return "User{" +
"id=" + id +
", name='" + name + '\'' +
", age=" + age +
'}';
}
}
六、在resoures下创建mybatis文件夹，添加Mapper的XML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.example.mapper.UserMapper">
<resultMap id="BaseResultMap" type="com.example.dto.User">
<id column="id" property="id" jdbcType="BIGINT"/>
<result column="name" property="name" jdbcType="VARCHAR"/>
<result column="age" property="age" jdbcType="TINYINT"/>
</resultMap>
<sql id="Base_Column_List">
id, name, age
</sql>
<select id="getById" resultMap="BaseResultMap" parameterType="java.lang.Long">
select
<include refid="Base_Column_List"/>
from test_user
where id = #{id,jdbcType=BIGINT}
</select>
<insert id="insert" parameterType="com.example.dto.User" useGeneratedKeys="true"
keyProperty="id">
insert into test_user (id,name,age)
values (#{id,jdbcType=BIGINT},
#{name,jdbcType=VARCHAR}, #{age,jdbcType=TINYINT})
</insert>
</mapper>
与普通的mybatis配置一样，只是小心：
-
mapper的命名空间（namespace），一定是所对应的接口的包名+类名
-
parameterType和resultMap，与实际匹配
七、接口文件
package com.example.mapper;
import com.example.dto.User;
public interface TestUserMapper {
/**
* getById 正常int主键的
*
* @param id
* @return
*/
User getById(final Long id);
}
注意：
-
类上没有任何的声明
-
方法的名称、输入参数书，与xml定义的一直
八、controller
package com.example.web;
import com.example.mapper.TestUserMapper;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
@RestController
@EnableAutoConfiguration
public class Example {
@Autowired
private TestUserMapper testUserMapper;
@RequestMapping("/getUser/{id}")
String getUser(@PathVariable Long id) {
return testUserMapper.getById(id).toString();
}
}
九、访问
运行成功后，打开浏览器，输入http://localhost:8080/getUser/1
页面展示TestUser{id=1, name='张三', age=18}
