springboot整合mybatis-高效篇

1、导入依赖

<dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>1.3.2</version>
        </dependency>

2、在配置文件中配置数据库连接信息

#DB Configation
spring.datasource.driver-class-name=com.mysql.jdbc.Driver
spring.datasource.url=jdbc:mysql://127.0.0.1:3306/users
spring.datasource.username=root
spring.datasource.password=root
# JPAConfiguration
spring.jpa.database=MySQL
spring.jpa.show-sql=true
spring.jpa.generate-ddl=true

或者：在yml配置文件中格式如下(仅mybatis)

spring:
  datasource:
    driverClassName: com.mysql.jdbc.Driver
    url: jdbc:mysql://127.0.0.1:3306/users
    username: root
    password: root

3、创建数据库对应实体类

在这使用了lombook插件，省略了set，get等方法

@Data
@NoArgsConstructor
@AllArgsConstructor
@ToString
public class Muser implements Serializable {
    private int uid;
    private String uname;
    private String pwd;
}

4、写对应操作的mapper接口以及sql映射文件

public interface UserMapper  {
    List<Muser> getAll();
}

<?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.ghh.staticdemo.mapper.UserMapper">
    <select id="getAll" resultType="com.ghh.staticdemo.pojo.Muser">
    select * from users
  </select>
</mapper>

注意更改namespace以及selcet的id属性

5、在启动类上加注解

@MapperScan("需要扫描的包")，相当于ssm框架中spring中的两个配置文件，SqlSessionfactory和mapperScannerConfigure两个bean对象

@SpringBootApplication
@MapperScan("com.ghh.staticdemo.mapper") //配置需要扫描的mapper接口所在包下
public class StaticdemoApplication {

    public static void main(String[] args) {
        SpringApplication.run(StaticdemoApplication.class, args);
    }
}

6、在controller层注入mapper接口，获取其代理类对象

@Resource
    private UserMapper userMapper;

@GetMapping("findAll")
public ModelAndView getAll(){
        ModelAndView mv = new ModelAndView("user");
        List<Muser> list =  userMapper.getAll();
        mv.addObject("userList",list);
        return mv;
    }  

至此配置完成

但我们在启动项目去访问时，会报找不到映射文件

1、需要我们在pom文件中配置一下代码避免打包时java目录下的XML文件被自动忽略掉：

<build>
        <resources>
            <resource>
                <directory>src/main/java</directory>
                <includes>
                    <include>**/*.properties</include>
                    <include>**/*.xml</include>
                </includes>
                <filtering>false</filtering>
            </resource>
            <resource>
                <directory>src/main/resources</directory>
                <includes>
                    <include>**/*.*</include>
                </includes>
                <filtering>false</filtering>
            </resource>
        </resources>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

2、或者在resources文件夹下创建与对应mapper接口相同文件路径的包下