spingboot-mybatis

一、springboot-mybatis

1.1 坐标

<parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.3.2.RELEASE</version>
        <relativePath/>
</parent>

<properties>
        <java.version>1.8</java.version>
    </properties>

    <dependencies>
        <!--web核心依赖-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-jdbc</artifactId>
        </dependency>

        <!--mysql数据库驱动-->
        <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>2.1.0</version>
        </dependency>

       <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>
    </dependencies>


    <build>
        <!--  扫描java下面的mapper文杰 -->
        <!-- ......用于扫描 dao 文件下的mapper 文件................. start -->
        <resources>
            <!-- 编译 src/main/java 目录下的 mapper 文件 -->
            <resource>
                <directory>src/main/java</directory>
                <includes>
                    <include>**/*.xml</include>
                </includes>
                <filtering>false</filtering>
            </resource>
        </resources>
        <!-- ......用于扫描 dao 文件下的mapper 文件................. end -->
    </build>

1.2 配置文件

连接配置

server:
  port: 8081
spring:
  datasource:
    driver-class-name: com.mysql.jdbc.Driver
    # driver-class-name: com.mysql.cj.jdbc.Driver
    url: jdbc:mysql:///demo?characterEncoding=utf-8&useSSL=false
    # ?useUnicode=true&characterEncoding=utf-8&useSSL=true&serverTimezone=UTC
    username: root
    password: root

mybatis:
  # 指定全局配置文件位置
  config-location: classpath:mybatis-config.xml
  # 指定sql映射文件位置
  mapper-locations: classpath:mapper/*.xml

#showSql
logging:
  level:
    com:
      three:
        mapper : debug

第一种配置
resources + myabtis-config.xml

配置

mybatis:
  config-location: classpath:mybatis-config.xml

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>
    <mappers>
        <mapper resource="mapper/UserMapper.xml"/>
    </mappers>
</configuration>

第二种配置
resources + application.yml

mybatis:
# 斜杠和点号都可以
#  mapper-locations: classpath*:com.example.mapper/*.xml
  mapper-locations: classpath*:com/example/mapper/*.xml
  type-aliases-package: com.example.bean
  config-location: classpath:mybatis-config.xml
  configuration:
 	map-underscore-to-camel-case: true

第三种配置
java + properties.yml

mybatis:
	mapper-locations: classpath*:mapper/*.xml
  #  type-aliases-package: com.example.bean
#  config-location: classpath:mybatis-config.xml
#  configuration:
#    map-underscore-to-camel-case: true

解决idea报错问题

@Component("userMapper")
@Mapper
public interface UserMapper {
    
    
    List<User> findAll();
}