用完spring-data-jpa之后并不是很想用mybatis,但是没办法呀，大环境还是mybatis，而且现在mybatis也出了不少插件，我们还是一起看看如何整合mybatis吧

关于整合mybatis有两种方式，一种是注解方式，另一种是传统的xml方式

注解方式

先看看引入的依赖

             
                  
       
        org.springframework.boot
                   
       
        spring-boot-starter-web
               
              
                  
       
        org.mybatis.spring.boot
                   
       
        mybatis-spring-boot-starter
                   
       
        1.3.2
               
              
                  
       
        mysql
                   
       
        mysql-connector-java
                   
       
        runtime
               
              
                  
       
        org.springframework.boot
                   
       
        spring-boot-starter-test
                   
       
        test
               
          
     

sql文件

CREATE TABLE `test`.`Untitled`  (  `id` int(11) NOT NULL AUTO_INCREMENT,  `name` varchar(255) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL,  `passwd` varchar(255) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL,  PRIMARY KEY (`id`) USING BTREE) ENGINE = InnoDB AUTO_INCREMENT = 4 CHARACTER SET = utf8 COLLATE = utf8_general_ci ROW_FORMAT = Dynamic;

application.properties

spring.datasource.driver-class-name=com.mysql.jdbc.Driverspring.datasource.url=jdbc:mysql:///test?useSSL=truespring.datasource.username=rootspring.datasource.password=root#打印sql语句到控制台logging.level.com.priv.gabriel.demoformybatis.mapper=debug

User.java

package com.priv.gabriel.demoformybatis.entity;/** * Created with Intellij IDEA. * * @Author: Gabriel * @Date: 2018-10-14 * @Description: */public class User {    private long id;    private String username;    private String passwd;    public long getId() {        return id;    }    public void setId(long id) {        this.id = id;    }    public String getUsername() {        return username;    }    public void setUsername(String username) {        this.username = username;    }    public String getPasswd() {        return passwd;    }    public void setPasswd(String passwd) {        this.passwd = passwd;    }}

UserMapper.java

package com.priv.gabriel.demoformybatis.mapper;import com.priv.gabriel.demoformybatis.entity.User;import org.apache.ibatis.annotations.*;/** * Created with Intellij IDEA. * * @Author: Gabriel * @Date: 2018-10-14 * @Description: */@Mapperpublic interface UserMapper {    /*注解方式的话直接在方法上写上对应的sql语句就可以了*/    @Select("select * from user where id = #{id}")    /*如果需要重复使用该Result,给该Results加一个 id 属性，下面即可使用@ResultMap(id)重复调用*/    @Results(id = "user",value = {            @Result(property = "username",column = "name")    })    User findById(long id);    /*获取回传自增id*/    /*id会自动存入user中*/    @Insert("insert into user(name,passwd) values (#{username},#{passwd})")    @Options(useGeneratedKeys = true,keyProperty = "id")    int inertUser(User user);}

UserController.java

package com.priv.gabriel.demoformybatis.controller;import com.priv.gabriel.demoformybatis.entity.User;import com.priv.gabriel.demoformybatis.mapper.UserMapper;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.web.bind.annotation.PathVariable;import org.springframework.web.bind.annotation.RequestMapping;import org.springframework.web.bind.annotation.RequestMethod;import org.springframework.web.bind.annotation.RestController;import java.util.List;/** * Created with Intellij IDEA. * * @Author: Gabriel * @Date: 2018-10-14 * @Description: */@RestController@RequestMapping("/users")public class UserController {    @Autowired    private UserMapper userMapper;    @RequestMapping(value = "/{id}",method = RequestMethod.GET)    public User selectById(@PathVariable long id){        return userMapper.findById(id);    }    @RequestMapping(value = {""},method = RequestMethod.POST)    public String addUser(User user){        userMapper.inertUser(user);        return "现在自增id为"+user.getId();    }}

在SpringBoot1.x中还需要在启动类中加入@MapperScan("mapper所在目录"),而在2.x版本中不需要加入就可以自动扫描到mapper了

加入分页

需要引入pageHelper依赖

             
                 
      
       com.github.pagehelper
                  
      
       pagehelper-spring-boot-starter
                  
      
       1.2.5
              
     

在UserMapper中新增一个查询所有信息的方法

@Select("select * from user")    /*调用之前的Results*/    @ResultMap("user")    List
     
       listUser();
     

在Controller中调用

/*获取分页数据 包含分页详细信息*/    @RequestMapping(value = "/",method = RequestMethod.GET)    public PageInfo getAll(@RequestParam Integer page, @RequestParam Integer size){        PageHelper.startPage(page,size);        List
     
       users = userMapper.listUser();        PageInfo
      
        pageInfo = new PageInfo(users);        return pageInfo;    }    /*仅获取分页数据    @RequestMapping(value = "/",method = RequestMethod.GET)    public List
       
         getAll(@RequestParam Integer page, @RequestParam Integer size){        PageHelper.startPage(page,size);        List
        
          users = userMapper.listUser();        return users;    }*/
        
       
      
     

XML方式

xml方式的话和以前Spring整合mybatis没有太大的区别，在这里可以使用Mybatis-Generator自动生成代码少些一点代码，其余的话就不多介绍了

整合通用Mapper

不管是使用注解方式还是XML方式都还是会存在一个什么都得自己动手的情况，接下来的话，我们整合一个通用的Mapper，在mybatis中体验jpa的感觉

引用依赖

             
                 
      
       tk.mybatis
                  
      
       mapper-spring-boot-starter
                  
      
       2.0.4
              
     

继承BaseMapper

package com.priv.gabriel.demoformybatis.mapper;import com.priv.gabriel.demoformybatis.entity.User;import org.apache.ibatis.annotations.Mapper;import tk.mybatis.mapper.common.BaseMapper;/** * Created with Intellij IDEA. * * @Author: Gabriel * @Date: 2018-10-14 * @Description: */@Mapperpublic interface UserCommonMapper extends BaseMapper
     
       {}
     

接着在Controller中调用

@Autowired    private UserCommonMapper mapper;    @RequestMapping("/testCommonMapperForSelectAll")    public List
     
       testCommonMapper(){        return mapper.selectAll();    }
     

关于mybatis的扩展很多，还有像mybatis-plus，关于这个话有时间再说吧，ε=ε=ε=┏(゜ロ゜;)┛