springboot整合mybatis的三种方式

首先引入jar包：

<parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.4.1.RELEASE</version>
    </parent>
    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <java.version>1.8</java.version>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <!-- https://mvnrepository.com/artifact/javax.servlet/javax.servlet-api -->
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>javax.servlet-api</artifactId>
            <version>3.1.0</version>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-tomcat</artifactId>
            <scope>provided</scope>
        </dependency>
        <!-- https://mvnrepository.com/artifact/org.apache.tomcat.embed/tomcat-embed-jasper -->
        <dependency>
            <groupId>org.apache.tomcat.embed</groupId>
            <artifactId>tomcat-embed-jasper</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <optional>true</optional> <!-- 这个需要为 true 热部署才有效 -->
            <scope>true</scope>
        </dependency>
        <!-- https://mvnrepository.com/artifact/mysql/mysql-connector-java -->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.30</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/org.mybatis.spring.boot/mybatis-spring-boot-starter -->
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>1.2.0</version>
        </dependency>
    </dependencies>
    <build>
        <finalName>springboot1</finalName>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <configuration>
                    <fork>true</fork>
                </configuration>
                <dependencies>
                    <dependency>
                        <groupId>org.springframework</groupId>
                        <artifactId>springloaded</artifactId>
                        <version>1.2.6.RELEASE</version>
                    </dependency>
                </dependencies>
            </plugin>
        </plugins>

    </build>

application.properties

spring.mvc.view.prefix=/WEB-INF/jsp/
spring.mvc.view.suffix=.jsp
spring.datasource.driver-class-name=com.mysql.jdbc.Driver
spring.datasource.url=jdbc:mysql://localhost:3306/jld
spring.datasource.username=root
spring.datasource.password=Root123456!

第一种方式：

在启动类上添加mapper扫描注解，

@SpringBootApplication
@MapperScan("com.jiulin.*.mapper")
public class App {
    public static void main(String[] args) {
        SpringApplication.run(App.class,args);
    }
}

controller

@Controller
public class UserController {

    @Autowired
    private IUserService userService;

    @RequestMapping("/toLogin")
    public String toLogin(){
        return "login";
    }
    @RequestMapping("/login")
    public String login(User user,Map<String,Object> map){
        User user1 = userService.login(user.getUserId(),user.getPassword());
        if (user1!=null){
            map.put("userId",user.getUserName());
            return "index";
        }else {
            return "redirect:/toLogin";
        }
    }
}

service

@Service
public class UserServiceImpl implements IUserService {

    @Autowired
    private UserMapper userMapper;

    @Override
    public User login(String username, String password)
    {
        User userTemp = userMapper.getStaffByUserName(username);
        if (userTemp != null && MD5.encodeByMd5AndSalt(password).equals(userTemp.getPassword()))
        {
            return userTemp;
        }
        return null;
    }
}

mapper

public interface UserMapper {

    @Results({ @Result(column = "id", property = "id", jdbcType = JdbcType.INTEGER),
            @Result(column = "userId", property = "userId", jdbcType = JdbcType.VARCHAR),
            @Result(column = "staffName", property = "userName", jdbcType = JdbcType.VARCHAR),
            @Result(column = "passwd", property = "password", jdbcType = JdbcType.VARCHAR), })
    @Select("select * from offline_staff where userId=#{userId}")
    User getStaffByUserName(@Param("userId") String userId);

第二种方式：在启动类上不加   @MapperScan("com.jiulin.*.mapper")   在mapper上家@Mapper注解

第三种方式：

在application.properties上加上mybatis的配置文件路径：mybatis.config-location=classpath:mybatis-config.xml

编写mybatis-config.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configuration PUBLIC "-//mybatis.org//DTD Config 3.0//EN" "http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
    <settings>
        <setting name="cacheEnabled" value="false"/>
        <setting name="localCacheScope" value="STATEMENT"/>
        <setting name="jdbcTypeForNull" value="NULL"/>
    </settings>
    <mappers>
        <package name="com.jiulin.user.mapper" />
    </mappers>
</configuration>