SpringBoot继承通用Mapper

一、为什么要用通用Mapper？

这段实时间自己在空余时间，改变了一下SpringBoot项目中使用mybatis的方式。之前一直都是使用的mybatis-generator插件生成一大堆Mapper相关的java文件和xml文件，虽然都是自动生成的，但总觉得不够干净，于是便想着做点什么——使用通用Mapper。

通用Mapper(tk.mybatis)封装了数据库表基本的CRUD功能，我们可以直接在业务方法中进行调用。使用之后，再也看不到那么多大同小异的自动生成的mapper相关文件。当然了，因为我们使用的数据库持久化框架是mybatis，很多时候，我们需要自定义查询，那么定义相关的java文件和xml文件是必须的。

集成的过程中，并不太顺利，网上找了各种资料，很混乱。所以自己在这里总结一下，同大家分享。

二、集成步骤

1.添加相关依赖

    org.mybatis.spring.boot
	mybatis-spring-boot-starter
	1.3.2




	tk.mybatis
	mapper-spring-boot-starter
	2.0.4

2.自定义Mapper继承通用Mapper

package com.gui.star.dal.common;

import tk.mybatis.mapper.common.Mapper;

public interface CommonMapper extends Mapper {

}

3.所有自己的xxxMapper.java继承第2步定义的Mapper

package com.gui.star.dal.mapper;

import com.gui.star.dal.common.CommonMapper;
import com.gui.star.dal.model.User;

public interface UserMapper extends CommonMapper{
	
}

4.定义通用的service使用封装好的CRUD操作

package com.gui.star.biz.common;

import java.util.List;

public interface BaseService {

    List findAll();

    T findById(Long id);

    int save(T t);

    int update(T t);

    int remove(Long id);
}

package com.gui.star.biz.common;

import java.util.List;

import com.gui.star.dal.common.CommonMapper;

public abstract class BaseServiceImpl implements BaseService {

    public abstract CommonMapper getMapper();

    @Override
    public List findAll() {
        return getMapper().selectAll();
    }

    @Override
    public T findById(Long id) {
        return getMapper().selectByPrimaryKey(id);
    }

    @Override
    public int save(T t) {
         return getMapper().insert(t);
    }

    @Override
    public int remove(Long id) {
        return getMapper().deleteByPrimaryKey(id);
    }

    @Override
    public int update(T t) {
        return getMapper().updateByPrimaryKey(t);
    }
}

5.业务service继承通用的BaseService

package com.gui.star.biz.service.impl;

import java.util.ArrayList;
import java.util.List;

import org.springframework.beans.BeanUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import com.gui.star.biz.common.BaseServiceImpl;
import com.gui.star.biz.service.UserService;
import com.gui.star.biz.vo.UserVo;
import com.gui.star.common.form.UserForm;
import com.gui.star.common.util.DomainUtil;
import com.gui.star.common.util.ObjectUtil;
import com.gui.star.dal.common.CommonMapper;
import com.gui.star.dal.mapper.UserMapper;
import com.gui.star.dal.model.User;

import lombok.extern.slf4j.Slf4j;

@Service
@Slf4j
public class UserServiceImpl extends BaseServiceImpl implements UserService {
	@Autowired
	private UserMapper userMapper;

	@Override
	public CommonMapper getMapper() {
		return this.userMapper;
	}

}

6.配置Mapper扫描已经修改配置文件

启动类中增加MapperScan注解扫描我们的Mapper

package com.gui.star.web;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.scheduling.annotation.EnableScheduling;

import tk.mybatis.spring.annotation.MapperScan;

/**
 * SpringBoot启动类
 * 
 *
 */
@SpringBootApplication
@ComponentScan(basePackages = "com.gui")
@MapperScan(basePackages = "com.gui.star.dal.mapper")
@EnableAutoConfiguration
@EnableScheduling
public class Application {
	public static void main(String[] args) {
		SpringApplication.run(Application.class, args);
	}
}

注意：这里的MapperScan对应导入的包是tk.mybatis.spring.annotation.MapperScan。

application.yml配置文件中mybatis的配置：

mybatis: 
  mapper-locations: classpath:mapper/*.xml  #注意：一定要对应mapper映射xml文件的所在路径
  type-aliases-package: com.gui.star.dal.model  # 注意：对应实体类的路径

7.对应的实体类

package com.gui.star.dal.model;

import java.util.Date;

import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;

public class User {
	/**
	 * 标识主键
	 * 定义ID的生成规则，每次保存后返回ID
	 */
	@Id
    @GeneratedValue(strategy=GenerationType.IDENTITY)
    private Long id;

    private String loginname;

    private String password;

    private String email;

    private String phone;

    private Date createdAt;

    private Date updatedAt;

    private Byte deleted;

    public Long getId() {
        return id;
    }

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

    public String getLoginname() {
        return loginname;
    }

    public void setLoginname(String loginname) {
        this.loginname = loginname == null ? null : loginname.trim();
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password == null ? null : password.trim();
    }

    public String getEmail() {
        return email;
    }

    public void setEmail(String email) {
        this.email = email == null ? null : email.trim();
    }

    public String getPhone() {
        return phone;
    }

    public void setPhone(String phone) {
        this.phone = phone == null ? null : phone.trim();
    }

    public Date getCreatedAt() {
        return createdAt;
    }

    public void setCreatedAt(Date createdAt) {
        this.createdAt = createdAt;
    }

    public Date getUpdatedAt() {
        return updatedAt;
    }

    public void setUpdatedAt(Date updatedAt) {
        this.updatedAt = updatedAt;
    }

    public Byte getDeleted() {
        return deleted;
    }

    public void setDeleted(Byte deleted) {
        this.deleted = deleted;
    }
}