一并附上 Mybatis 和 Mybatis Plus 的使用区别
MyBatis Mapper.XML 标签使用说明
Pom 依赖
Mybatis
<!-- 统一管理 jar 包版本 --> <properties> <druid-boot.version>1.1.10</druid-boot.version> <mybatis-boot.version>2.1.0</mybatis-boot.version> <mysql-connector.version>8.0.16</mysql-connector.version> <mssql-jdbc.version>8.2.2.jre8</mssql-jdbc.version> <oracle-jdbc.version>19.3.0.0</oracle-jdbc.version> <pagehelper-starter.version>1.2.10</pagehelper-starter.version> </properties> <!--子模块继承之后，锁定版本+子模块不用写 groupid 和 version --> <dependencyManagement> <dependencies> <!-- mybatis + druid + mysql + mssql--> <dependency> <groupId>com.alibaba</groupId> <artifactId>druid-spring-boot-starter</artifactId> <version>${druid-boot.version}</version> </dependency> <dependency> <groupId>org.mybatis.spring.boot</groupId> <artifactId>mybatis-spring-boot-starter</artifactId> <version>${mybatis-boot.version}</version> </dependency> <dependency> <groupId>com.github.pagehelper</groupId> <artifactId>pagehelper-spring-boot-starter</artifactId> <version>${pagehelper-starter.version}</version> </dependency> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <version>${mysql-connector.version}</version> </dependency> <dependency> <groupId>com.microsoft.sqlserver</groupId> <artifactId>mssql-jdbc</artifactId> <version>${mssql-jdbc.version}</version> </dependency> <dependency> <groupId>com.oracle.database.jdbc</groupId> <artifactId>ojdbc8</artifactId> <version>${oracle-jdbc.version}</version> </dependency> <!-- mybatis + druid + mysql + mssql--> </dependencies> </dependencyManagement> Mybatis Plus
使用框架自带的分布控件，如果使用 pagehelper 会报 JSqlParser 的版本冲突，根据情况排除 pagehelper 版本（不推荐）。
<!-- 统一管理 jar 包版本 --> <properties> <druid-boot.version>1.2.23</druid-boot.version> <mybatis-plus.version>3.5.7</mybatis-plus.version> <mysql-connector.version>8.0.33</mysql-connector.version> <mssql-jdbc.version>8.2.2.jre8</mssql-jdbc.version> <oracle-jdbc.version>19.3.0.0</oracle-jdbc.version> </properties> <!--子模块继承之后，锁定版本+子模块不用写 groupid 和 version --> <dependencyManagement> <dependencies> <!-- mybatis plus + druid + mysql + mssql--> <dependency> <groupId>com.baomidou</groupId> <artifactId>mybatis-plus-boot-starter</artifactId> <version>${mybatis-plus.version}</version> </dependency> <!--分页--> <dependency> <groupId>com.baomidou</groupId> <artifactId>mybatis-plus-extension</artifactId> <version>${mybatis-plus.version}</version> </dependency> <dependency> <groupId>com.baomidou</groupId> <artifactId>mybatis-plus-annotation</artifactId> <version>${mybatis-plus.version}</version> </dependency> <dependency> <groupId>com.alibaba</groupId> <artifactId>druid-spring-boot-starter</artifactId> <version>${druid-boot.version}</version> </dependency> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-j</artifactId> <version>${mysql-connector.version}</version> </dependency> <dependency> <groupId>com.microsoft.sqlserver</groupId> <artifactId>mssql-jdbc</artifactId> <version>${mssql-jdbc.version}</version> </dependency> <dependency> <groupId>com.oracle.database.jdbc</groupId> <artifactId>ojdbc8</artifactId> <version>${oracle-jdbc.version}</version> </dependency> <!-- mybatis plus + druid + mysql + mssql--> </dependencies> </dependencyManagement> yml 配置
Mybatis
mybatis: # 指定sql映射文件位置 mapper-locations: classpath*:mapper/*.xml configuration: map-underscore-to-camel-case: true log-impl: org.apache.ibatis.logging.stdout.StdOutImpl type-handlers-package: com.vipsoft.base.handler # MySQL 8.0 用以mysql中json格式的字段，进行转换的自定义转换器，转换为实体类的JSONObject属性 Mybatis-Plus
mybatis-plus: mapper-locations: classpath*:mapper/*Mapper.xml global-config: banner: true db-config: id-type: auto where-strategy: not_empty insert-strategy: not_empty update-strategy: not_null type-handlers-package: com.vipsoft.base.handler # MySQL 8.0 用以mysql中json格式的字段，进行转换的自定义转换器，转换为实体类的JSONObject属性 configuration: log-impl: org.apache.ibatis.logging.stdout.StdOutImpl map-underscore-to-camel-case: true jdbc-type-for-null: 'null' call-setters-on-nulls: true shrink-whitespaces-in-sql: true druid
SpringBoot 配置多数据源
spring: profiles: active: dev resources: static-locations: classpath:/META-INF/resources/,classpath:/resources/,classpath:/static/,classpath:/public/,classpath:/web/,file:${cuwor.file.path} datasource: type: com.alibaba.druid.pool.DruidDataSource driver-class-name: com.mysql.cj.jdbc.Driver #数据源基本配置 url: jdbc:mysql://192.168.1.100:3306/production_education?serverTimezone=Asia/Shanghai&useUnicode=true&characterEncoding=utf8&zeroDateTimeBehavior=CONVERT_TO_NULL username: root password: root #连接池的设置 druid: initial-size: 5 #初始化时建立物理连接的个数 min-idle: 5 #最小连接池数量 max-active: 200 #最大连接池数量 maxIdle已经不再使用 max-wait: 60000 #获取连接时最大等待时间，单位毫秒 test-while-idle: true #申请连接的时候检测，如果空闲时间大于timeBetweenEvictionRunsMillis，执行validationQuery检测连接是否有效。 time-between-eviction-runs-millis: 60000 #既作为检测的间隔时间又作为testWhileIdel执行的依据 #销毁线程时检测当前连接的最后活动时间和当前时间差大于该值时，关闭当前连接 min-evictable-idle-time-millis: 30000 validation-query: select 'x' #用来检测连接是否有效的sql 必须是一个查询语句（ mysql中为 select 'x' oracle中为 select 1 from dual） test-on-borrow: false #申请连接时会执行validationQuery检测连接是否有效,开启会降低性能,默认为true test-on-return: false #归还连接时会执行validationQuery检测连接是否有效,开启会降低性能,默认为true #exception-sorter: true #当数据库抛出不可恢复的异常时,抛弃该连接 #pool-prepared-statements: true #是否缓存preparedStatement,mysql5.5+建议开启 max-pool-prepared-statement-per-connection-size: 20 #当值大于0时poolPreparedStatements会自动修改为true filters: stat,wall #配置扩展插件 connection-properties: druid.stat.mergeSql=true;druid.stat.slowSqlMillis=500 #通过connectProperties属性来打开mergeSql功能；慢SQL记录 use-global-data-source-stat: true #合并多个DruidDataSource的监控数据 #设置访问druid监控页的账号和密码,默认没有--放DrugConfig配置中 #stat-view-servlet.login-username: admin #stat-view-servlet.login-password: admin Config 配置
Druid 配置没有变化
package com.vipsoft.base.config; import com.alibaba.druid.pool.DruidDataSource; import com.alibaba.druid.support.http.StatViewServlet; import com.alibaba.druid.support.http.WebStatFilter; import org.springframework.boot.context.properties.ConfigurationProperties; import org.springframework.boot.web.servlet.FilterRegistrationBean; import org.springframework.boot.web.servlet.ServletRegistrationBean; import org.springframework.context.annotation.Bean; import org.springframework.context.annotation.Configuration; import javax.sql.DataSource; import java.util.Arrays; import java.util.HashMap; import java.util.Map; @Configuration public class DruidConfig { @ConfigurationProperties(prefix = "spring.datasource") @Bean public DataSource druid(){ return new DruidDataSource(); } //配置Druid的监控 //1、配置一个管理后台的Servlet @Bean public ServletRegistrationBean statViewServlet(){ ServletRegistrationBean bean = new ServletRegistrationBean(new StatViewServlet(), "/druid/*"); Map<String,String> initParams = new HashMap<>(); initParams.put("loginUsername","admin"); initParams.put("loginPassword","vipsoft"); initParams.put("resetEnable","false"); initParams.put("allow","");//默认就是允许所有访问 initParams.put("deny","192.168.15.21"); //IP黑名单（同时存在时，deny优先于allow） bean.setInitParameters(initParams); return bean; } //2、配置一个web监控的filter @Bean public FilterRegistrationBean webStatFilter(){ FilterRegistrationBean bean = new FilterRegistrationBean(); bean.setFilter(new WebStatFilter()); Map<String,String> initParams = new HashMap<>(); initParams.put("exclusions","*.js,*.css,/druid/*"); bean.setInitParameters(initParams); bean.setUrlPatterns(Arrays.asList("/*")); return bean; } } Mybatis Plus 分页，需要添加 拦截器配置，否则分页不生效
package com.vipsoft.base.config; import com.baomidou.mybatisplus.extension.plugins.MybatisPlusInterceptor; import com.baomidou.mybatisplus.extension.plugins.inner.PaginationInnerInterceptor; import org.springframework.context.annotation.Bean; import org.springframework.context.annotation.Configuration; @Configuration public class MybatisPlusConfig { /** * 分页插件 -- 否则分页不生效 * @return */ @Bean public MybatisPlusInterceptor mybatisPlusInterceptor() { MybatisPlusInterceptor interceptor = new MybatisPlusInterceptor(); interceptor.addInnerInterceptor(new PaginationInnerInterceptor()); return interceptor; } } 
Mapper扫描
@MapperScan({"com.vipsoft.admin.mapper"}) 和 Mybatis 无区别
package com.vipsoft.admin; import org.mybatis.spring.annotation.MapperScan; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; import org.springframework.context.annotation.ComponentScan; @ComponentScan(basePackages = {"com.vipsoft"}) @SpringBootApplication @MapperScan({"com.vipsoft.admin.mapper"}) public class VipSoftAdminApplication { public static void main(String[] args) { SpringApplication.run(VipSoftAdminApplication.class, args); } } Entity
SysMenu
//@TableName("sys_menu") 默认会将 SysMenu 解析成 sys_menu 如果解析后不是正确的表名，需要通过 TableName进行指定， public class SysMenu extends BaseEntity { private static final long serialVersionUID = 1L; /** 菜单ID */ @TableId(value = "menu_id", type = IdType.ASSIGN_ID) private Long menuId; /** 菜单名称 */ @TableField(value = "menu_name") private String menuName; /** 父菜单名称 */ @TableField(exist = false) //非数据库字段，进行排除 private String parentName; ....省略 } Mapper.xml
SysMenuMapper.xml
<?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.vipsoft.admin.mapper.SysMenuMapper"> <resultMap type="com.vipsoft.admin.entity.SysMenu" id="SysMenuResult"> <id property="menuId" column="menu_id"/> <result property="menuName" column="menu_name"/> <result property="parentName" column="parent_name"/> <result property="parentId" column="parent_id"/> <result property="orderNum" column="order_num"/> <result property="path" column="path"/> <result property="createTime" column="create_time"/> <result property="updateTime" column="update_time"/> </resultMap> <select id="listMenu" parameterType="com.vipsoft.admin.entity.SysMenu" resultMap="SysMenuResult"> select menu_id, menu_name, parent_id, order_num, create_time from sys_menu <where> <if test="menuName != null and menuName != ''"> AND menu_name like concat('%', #{menuName}, '%') </if> <if test="visible != null and visible != ''"> AND visible = #{visible} </if> <if test="status != null and status != ''"> AND status = #{status} </if> </where> order by parent_id, order_num </select> <select id="listMenuPage" resultMap="SysMenuResult"> select menu_id, menu_name, parent_id, order_num, create_time from sys_menu <where> <if test="query.menuName != null and query.menuName != ''"> AND menu_name like concat('%', #{query.menuName}, '%') </if> <if test="query.visible != null and query.visible != ''"> AND visible = #{query.visible} </if> <if test="query.status != null and query.status != ''"> AND status = #{query.status} </if> </where> order by parent_id, order_num </select> </mapper>
Mapper - SysMenuMapper
需要继承 BaseMapper
package com.vipsoft.admin.mapper; import com.baomidou.mybatisplus.core.mapper.BaseMapper; import com.baomidou.mybatisplus.core.metadata.IPage; import com.baomidou.mybatisplus.extension.plugins.pagination.Page; import com.vipsoft.admin.entity.SysMenu; import org.apache.ibatis.annotations.Param; import java.util.List; /** * 菜单表 数据层 */ public interface SysMenuMapper extends BaseMapper<SysMenu> { List<SysMenu> listMenu(SysMenu menu); IPage<SysMenu> listMenuPage(Page page, @Param("query") SysMenu menu); } Service
ISysMenuService
package com.vipsoft.admin.service; import com.baomidou.mybatisplus.core.metadata.IPage; import com.vipsoft.admin.entity.SysMenu; import java.util.List; /** * 菜单 业务层 * */ public interface ISysMenuService { /** * 列表查询(自定义SQL，分页) */ List<SysMenu> listMenu(SysMenu menu); /** * 列表查询（框架分页） */ IPage selectPage(SysMenu menu); /** * 列表查询（自定义SQL，分页） */ IPage listMenuPage(SysMenu menu); } SysMenuService
package com.vipsoft.admin.service.impl; import com.baomidou.mybatisplus.core.metadata.IPage; import com.baomidou.mybatisplus.core.metadata.OrderItem; import com.baomidou.mybatisplus.extension.plugins.pagination.Page; import com.vipsoft.admin.entity.SysMenu; import com.vipsoft.admin.mapper.SysMenuMapper; import com.vipsoft.admin.service.ISysMenuService; import com.github.pagehelper.PageHelper; import com.github.pagehelper.PageInfo; import com.github.pagehelper.PageParam; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Service; import java.util.*; import java.util.stream.Collectors; /** * 菜单 业务层处理 * * @author ruoyi */ @Service public class SysMenuServiceImpl implements ISysMenuService { @Autowired private SysMenuMapper menuMapper; /** * 列表查询(自定义SQL，分页) */ @Override public List<SysMenu> listMenu(SysMenu menu) { return menuMapper.listMenu(new SysMenu()); } /** * 列表查询（框架分页） */ @Override public IPage selectPage(SysMenu menu) { Page page = new Page(); page.setCurrent(2); page.setSize(10); List<OrderItem> orderItems = new ArrayList<>(); orderItems.add(OrderItem.desc("menu_id")); page.setOrders(orderItems); Page pageList = menuMapper.selectPage(page, null); return pageList; } /** * 列表查询（自定义SQL，分页） */ @Override public IPage listMenuPage(SysMenu menu) { Page page = new Page(); page.setCurrent(2); page.setSize(10); List<OrderItem> orderItems = new ArrayList<>(); orderItems.add(OrderItem.desc("menu_id")); //先按 menu_id 排序，再按 mapper.xml 中的排（可以在查询输出的SQL中查看） page.setOrders(orderItems); IPage<SysMenu> pageList = menuMapper.listMenuPage(page, menu); return pageList; } } Controller
package com.vipsoft.admin.controller; import com.baomidou.mybatisplus.core.metadata.IPage; import com.vipsoft.admin.entity.SysMenu; import com.vipsoft.admin.service.ISysMenuService; import com.vipsoft.base.core.ApiResult; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.web.bind.annotation.GetMapping; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RestController; import java.util.List; /** * 菜单信息 */ @RestController @RequestMapping("/menu") public class SysMenuController { @Autowired private ISysMenuService menuService; /** * 获取菜单列表 */ @GetMapping("/selectPage") public ApiResult selectPage(SysMenu menu) { IPage menus = menuService.selectPage(menu); return new ApiResult(menus); } /** * 获取菜单列表 */ @GetMapping("/list") public ApiResult listMenu(SysMenu menu) { List<SysMenu> menus = menuService.listMenu(menu); return new ApiResult(menus); } /** * 获取菜单列表 */ @GetMapping("/listMenuPage") public ApiResult listMenuPage(SysMenu menu) { IPage menus = menuService.listMenuPage(menu); return new ApiResult(menus); } } 
