从零搭建自己的SpringBoot后台框架(八)

Hello大家好，本章我们集成通用 Mapper功能 。有问题可以联系我mr_beany@163.com。另求各路大神指点，感谢

一：什么是通用 Mapper

通用 Mapper 是一个可以实现任意 MyBatis 通用方法的框架，项目提供了常规的增删改查操作以及 Example 相关的单表操作。通用 Mapper 是为了解决 MyBatis 使用中 90% 的基本操作，使用它可以很方便的进行开发，可以节省开发人员大量的时间。

二：添加mapper依赖

<dependency>
   <groupId>tk.mybatis</groupId>
   <artifactId>mapper-spring-boot-starter</artifactId>
   <version>2.0.1</version>
</dependency>

三：修改MybatisConfigurer配置文件

这里我们重新配置MapperScannerConfigurer

打开MybatisConfigurer

将import org.mybatis.spring.mapper.MapperScannerConfigurer;修改为

import tk.mybatis.spring.mapper.MapperScannerConfigurer;

四：创建通用mapper，service，serviceImpl

创建core→universal文件夹

创建以下文件

1、Mapper

package com.example.demo.core.universal;

import tk.mybatis.mapper.common.BaseMapper;
import tk.mybatis.mapper.common.ConditionMapper;
import tk.mybatis.mapper.common.IdsMapper;
import tk.mybatis.mapper.common.special.InsertListMapper;

/**
 * @Description: 定制版MyBatis Mapper插件接口，如需其他接口参考官方文档自行添加。
 * @author 张瑶
 * @date 2018/4/22 21:15
 */
public interface Mapper<T> extends BaseMapper<T>, ConditionMapper<T>, IdsMapper<T>, InsertListMapper<T> {
}

2、Service

package com.example.demo.core.universal;

import org.apache.ibatis.exceptions.TooManyResultsException;
import tk.mybatis.mapper.entity.Condition;

import java.util.List;

/**
 * @author 张瑶
 * @Description: Service层基础接口，其他Service接口请继承该接口
 * @date 2018/4/18 11:25
 */
public interface Service<T> {

    /**
     * @param model
     * @Description: 持久化
     * @Reutrn Integer
     */
    Integer insert(T model);

    /**
     * @param id
     * @Description: 通过主鍵刪除
     * @Reutrn Integer
     */
    Integer deleteById(String id);

    /**
     * @param ids
     * @Description: 批量刪除 eg：ids -> “1,2,3,4”
     * @Reutrn Integer
     */
    Integer deleteByIds(String ids);

    /**
     * @param model
     * @Description: 更新
     * @Reutrn Integer
     */
    Integer update(T model);

    /**
     * @param id
     * @Description: 通过ID查找
     * @Reutrn T
     */
    T selectById(String id);

    /**
     * @param fieldName
     * @param value
     * @throws TooManyResultsException
     * @Description: 通过Model中某个成员变量名称（非数据表中column的名称）查找,value需符合unique约束
     * @Reutrn T
     */
    T selectBy(String fieldName, Object value) throws TooManyResultsException;

    /**
     * @param fieldName javabean定义的属性名，不是数据库里的属性名
     * @param value
     * @Description: 通过Model中某个成员变量名称（非数据表中column的名称）查找
     * @Reutrn List<T>
     */
    List<T> selectListBy(String fieldName, Object value);

    /**
     * @param ids
     * @Description: 通过多个ID查找//eg：ids -> “1,2,3,4”
     * @Reutrn List<T>
     */
    List<T> selectListByIds(String ids);

    /**
     * @param condition
     * @Description: 根据条件查找
     * @Reutrn List<T>
     */
    List<T> selectByCondition(Condition condition);

    /**
     * @Description: 获取所有
     * @Reutrn List<T>
     */
    List<T> selectAll();

    /**
     * @param record
     * @return List<T>
     * @Description: 根据实体中的属性值进行查询，查询条件使用等号
     */
    List<T> select(T record);

    /**
     * @param record
     * @return T
     * @Description: 根据实体中的属性值进行查询，查询条件使用等号
     */
    T selectOne(T record);
}

3、AbsratctService

package com.example.demo.core.universal;

import com.example.demo.core.ret.ServiceException;
import org.apache.ibatis.exceptions.TooManyResultsException;
import org.springframework.beans.factory.annotation.Autowired;
import tk.mybatis.mapper.entity.Condition;

import java.lang.reflect.Field;
import java.lang.reflect.ParameterizedType;
import java.util.List;

/**
 * @Description: 基于通用MyBatis Mapper插件的Service接口的实现
 * @author 张瑶
 * @date 2018/4/18 11:28
 */
public abstract class AbstractService<T> implements Service<T> {

   @Autowired
   protected Mapper<T> mapper;

   private Class<T> modelClass; // 当前泛型真实类型的Class

   @SuppressWarnings("unchecked")
   public AbstractService() {
      ParameterizedType pt = (ParameterizedType) this.getClass().getGenericSuperclass();
      modelClass = (Class<T>) pt.getActualTypeArguments()[0];
   }

   @Override
   public Integer insert(T model) {
      return mapper.insertSelective(model);
   }

   @Override
   public Integer deleteById(String id) {
      return mapper.deleteByPrimaryKey(id);
   }

   @Override
   public Integer deleteByIds(String ids) {
      return mapper.deleteByIds(ids);
   }

   @Override
   public Integer update(T model) {
      return mapper.updateByPrimaryKeySelective(model);
   }

   @Override
   public T selectById(String id) {
      return mapper.selectByPrimaryKey(id);
   }

   @Override
   public T selectBy(String fieldName, Object value) throws TooManyResultsException {
      try {
         T model = modelClass.newInstance();
         Field field = modelClass.getDeclaredField(fieldName);
         field.setAccessible(true);
         field.set(model, value);
         return mapper.selectOne(model);
      } catch (ReflectiveOperationException e) {
         throw new ServiceException(e.getMessage(), e);
      }
   }

   @Override
   public List<T> selectListBy(String fieldName, Object value)  {
      try {
         T model = modelClass.newInstance();
         Field field = modelClass.getDeclaredField(fieldName);
         field.setAccessible(true);
         field.set(model, value);
         return mapper.select(model);
      } catch (ReflectiveOperationException e) {
         throw new ServiceException(e.getMessage(), e);
      }
   }

   @Override
   public List<T> selectListByIds(String ids) {
      return mapper.selectByIds(ids);
   }

   @Override
   public List<T> selectByCondition(Condition condition) {
      return mapper.selectByCondition(condition);
   }

   @Override
   public List<T> selectAll() {
      return mapper.selectAll();
   }

   @Override
   public List<T> select(T record){
      return mapper.select(record);
   }

   @Override
   public T selectOne(T recoed){
      return mapper.selectOne(recoed);
   }
}

五：添加mapper配置

在 application.properties 中添加

mapper.mappers=com.example.demo.core.universal.Mapper

六：修改model，dao，service，serviceImpl，controller层代码

注意，之前user_info表主键为int类型，现修改为varchar；

注意，使用通用mapper需要在实体类的id加上 @Id

1、UserInfo

package com.example.demo.model;

import javax.persistence.Column;
import javax.persistence.Id;

/**
 * @author 张瑶
 * @Description:
 * @time 2018/4/18 11:55
 */
public class UserInfo {

    /**
     * 主键
     */
    @Id
    private String id;

    /**
     * 用户名
     */
    @Column(name = "user_name")
    private String userName;

    public String getId() {
        return id;
    }

    public void setId(String id) {
        this.id = id;
    }

    public String getUserName() {
        return userName;
    }

    public void setUserName(String userName) {
        this.userName = userName;
    }
}

2、UserInfoMapper.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.example.demo.dao.UserInfoMapper">
    <resultMap id="BaseResultMap" type="com.example.demo.model.UserInfo">
        <id column="id" jdbcType="VARCHAR" property="id"/>
        <result column="user_name" jdbcType="VARCHAR" property="userName"/>
    </resultMap>

    <sql id="Base_Column_List">
      id,user_name
    </sql>

</mapper>

3、UserInfoMapper

package com.example.demo.dao;

import com.example.demo.core.universal.Mapper;
import com.example.demo.model.UserInfo;

/**
 * @author 张瑶
 * @Description:
 * @time 2018/4/18 11:54
 */
public interface UserInfoMapper extends Mapper<UserInfo>{
}

4、UserInfoService

package com.example.demo.service;

import com.example.demo.core.universal.Service;
import com.example.demo.model.UserInfo;

/**
 * @author 张瑶
 * @Description:
 * @time 2018/4/18 11:56
 */
public interface UserInfoService extends Service<UserInfo>{

}

5、UserInfoServiceImpl

package com.example.demo.service.impl;

import com.example.demo.core.universal.AbstractService;
import com.example.demo.core.ret.ServiceException;
import com.example.demo.dao.UserInfoMapper;
import com.example.demo.model.UserInfo;
import com.example.demo.service.UserInfoService;
import org.springframework.stereotype.Service;

import javax.annotation.Resource;

/**
 * @author 张瑶
 * @Description:
 * @time 2018/4/18 11:56
 */
@Service
public class UserInfoServiceImpl extends AbstractService<UserInfo> implements UserInfoService{

    @Resource
    private UserInfoMapper userInfoMapper;

    @Override
    public UserInfo selectById(String id){
        UserInfo userInfo = userInfoMapper.selectByPrimaryKey(id);
        if(userInfo == null){
            throw new ServiceException("暂无该用户");
        }
        return userInfo;
    }
}

6、UserInfoController

package com.example.demo.controller;

import com.example.demo.core.ret.RetResponse;
import com.example.demo.core.ret.RetResult;
import com.example.demo.model.UserInfo;
import com.example.demo.service.UserInfoService;
import com.github.pagehelper.PageHelper;
import com.github.pagehelper.PageInfo;
import io.swagger.annotations.Api;
import io.swagger.annotations.ApiImplicitParam;
import io.swagger.annotations.ApiImplicitParams;
import io.swagger.annotations.ApiOperation;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

import javax.annotation.Resource;
import java.util.List;

/**
 * @author 张瑶
 * @Description:
 * @time 2018/4/18 11:39
 */
@RestController
@RequestMapping("userInfo")
@Api(tags = {"用户操作接口"}, description = "userInfoControler")
public class UserInfoController {

    @Resource
    private UserInfoService userInfoService;

    @PostMapping("/hello")
    public String hello() {
        return "hello SpringBoot";
    }

    @ApiOperation(value = "查询用户", notes = "根据用户ID查询用户")
    @ApiImplicitParams({
            @ApiImplicitParam(name = "id", value = "用户ID", required = true,
                    dataType = "String", paramType = "query")
    })
    @PostMapping("/selectById")
    public RetResult<UserInfo> selectById(@RequestParam String id) {
        UserInfo userInfo = userInfoService.selectById(id);
        return RetResponse.makeOKRsp(userInfo);
    }

    @PostMapping("/testException")
    public RetResult<UserInfo> testException(String id) {
        List a = null;
        a.size();
        UserInfo userInfo = userInfoService.selectById(id);
        return RetResponse.makeOKRsp(userInfo);
    }

    @ApiOperation(value = "查询用户", notes = "分页查询用户所有")
    @ApiImplicitParams({
            @ApiImplicitParam(name = "page", value = "当前页码",
                    dataType = "Integer", paramType = "query"),
            @ApiImplicitParam(name = "size", value = "每页显示条数",
                    dataType = "Integer", paramType = "query")
    })
    @PostMapping("/selectAll")
    public RetResult<PageInfo<UserInfo>> selectAll(@RequestParam(defaultValue = "0") Integer page,
                                          @RequestParam(defaultValue = "0") Integer size) {
        PageHelper.startPage(page,size);
        List<UserInfo> userInfoList = userInfoService.selectAll();
        PageInfo<UserInfo> pageInfo = new PageInfo<>(userInfoList);
        return RetResponse.makeOKRsp(pageInfo);
    }


}

七：功能测试

ok，在没写sql的情况下，功能依旧好使

项目地址

gitee.com/beany/mySpr…

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结尾

集成通用 Mapper功能已完成，后续功能接下来陆续更新，有问题可以联系我mr_beany@163.com。另求各路大神指点，感谢大家。