SpringBoot整合MybatisPlus，并实现新增、修改、删除、查看、分页

在pom.xml中引入mybatis plus的jar包

        <!-- mybatis plus依赖包 -->
        <dependency>
            <groupId>com.baomidou</groupId>
            <artifactId>mybatis-plus-boot-starter</artifactId>
            <version>3.3.0</version>
        </dependency>

在resources/application.yml配置文件中配置数据库

#配置数据库
spring:
  datasource:
    driver-class-name: com.mysql.jdbc.Driver
    url: jdbc:mysql://localhost:3306/jeff?characterEncoding=utf8
    username: root
    password: mysql

创建BaseEntity实体类

package com.jeff.mybatis.plus.entity;

import java.util.Date;

import com.baomidou.mybatisplus.annotation.IdType;
import com.baomidou.mybatisplus.annotation.TableId;
import com.fasterxml.jackson.annotation.JsonFormat;

import lombok.Data;

@Data
public class BaseEntity {

    // 主键
    @TableId(type = IdType.AUTO)
    private Long id;

    // 创建时间
    @JsonFormat(pattern = "yyyy-MM-dd HH:mm:ss", timezone = "GMT+8")
    private Date createTime;

    // 创建人
    private String createName;

    // 修改时间
    @JsonFormat(pattern = "yyyy-MM-dd HH:mm:ss", timezone = "GMT+8")
    private Date modifyTime;

    // 修改人
    private String modifyName;

}

创建User实体类

package com.jeff.mybatis.plus.entity;

import java.util.Date;

import org.springframework.format.annotation.DateTimeFormat;

import com.baomidou.mybatisplus.annotation.FieldStrategy;
import com.baomidou.mybatisplus.annotation.TableField;
import com.baomidou.mybatisplus.annotation.TableName;
import com.fasterxml.jackson.annotation.JsonFormat;
import com.jeff.mybatis.plus.utils.DateUtils;

import lombok.Data;
import lombok.EqualsAndHashCode;

@Data
@TableName("sys_user")
@EqualsAndHashCode(callSuper = false)
public class User extends BaseEntity {

    // 登陆名
    private String loginName;

    // 密码
    private String password;

    // 盐
    private String salt;

    // 性别(0:保密;1:男;2:女)
    private Integer sex;

    // 状态(0:有效;1:无效)
    private Integer status;

    // 真实姓名
    private String name;

    // 昵称
    private String nickName;

    // 手机号
    private String phone;

    // 邮箱
    private String email;

    // 生日
    @TableField(updateStrategy = FieldStrategy.IGNORED)
    @DateTimeFormat(pattern = DateUtils.SHORT_TIME_FORMAT)
    @JsonFormat(pattern = DateUtils.SHORT_TIME_FORMAT, timezone = "GMT+8")
    private Date birthday;

    // 用户头像
    private String headimgUrl;

}

创建UserMapper

package com.jeff.mybatis.plus.mapper;

import org.apache.ibatis.annotations.Mapper;

import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import com.jeff.mybatis.plus.entity.User;

@Mapper
public interface UserMapper extends BaseMapper<User> {

}

创建UserService

package com.jeff.mybatis.plus.service;

import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import com.baomidou.mybatisplus.extension.service.IService;
import com.jeff.mybatis.plus.entity.User;
import com.jeff.mybatis.plus.entity.request.PageEntity;
import com.jeff.mybatis.plus.entity.request.UserParam;

public interface UserService extends IService<User> {

    boolean isExist(User user);

    Page<User> getList(PageEntity page, UserParam param);

}

创建UserServiceImpl

package com.jeff.mybatis.plus.service.impl;

import org.apache.commons.lang3.StringUtils;
import org.springframework.stereotype.Service;

import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.jeff.mybatis.plus.entity.User;
import com.jeff.mybatis.plus.entity.request.PageEntity;
import com.jeff.mybatis.plus.entity.request.UserParam;
import com.jeff.mybatis.plus.mapper.UserMapper;
import com.jeff.mybatis.plus.service.UserService;
import com.jeff.mybatis.plus.utils.DateUtils;

@Service
public class UserServiceImpl extends ServiceImpl<UserMapper, User> implements UserService {

    @Override
    public Page<User> getList(PageEntity pageEntity, UserParam param) {
        Page<User> page = new Page<User>(pageEntity.getPage(), pageEntity.getRows());
        QueryWrapper<User> wrapper = new QueryWrapper<User>();
        if (StringUtils.isNotBlank(param.getLoginName())) {
            wrapper.eq("login_name", param.getLoginName());
        }
        if (StringUtils.isNotBlank(param.getName())) {
            wrapper.like("name", param.getName());
        }
        if (param.getStartDate() != null) {
            wrapper.ge("create_time", DateUtils.getStartOfDay(param.getStartDate()));
        }
        if (param.getEndDate() != null) {
            wrapper.lt("create_time", DateUtils.getEndOfDay(param.getEndDate()));
        }
        wrapper.orderByDesc("id");
        return page(page, wrapper);
    }

    @Override
    public boolean isExist(User user) {
        QueryWrapper<User> wrapper = new QueryWrapper<User>();
        wrapper.eq("login_name", user.getLoginName());
        if (user.getId() != null) {
            wrapper.ne("id", user.getId());
        }
        return count(wrapper) > 0;
    }

}

创建UserController

package com.jeff.mybatis.plus.controller;

import java.util.Date;

import org.apache.commons.lang3.Validate;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.CrossOrigin;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import com.jeff.mybatis.plus.common.Constant;
import com.jeff.mybatis.plus.entity.User;
import com.jeff.mybatis.plus.entity.request.PageEntity;
import com.jeff.mybatis.plus.entity.request.UserParam;
import com.jeff.mybatis.plus.enums.ResponseCodes;
import com.jeff.mybatis.plus.service.UserService;
import com.jeff.mybatis.plus.utils.ResultsUtils;

@CrossOrigin("*")
@RestController
@RequestMapping("user")
public class UserController {

    @Autowired
    private UserService service;

    /**
     *
     * @description: 新增用户
     * @author: Jeff
     * @param user
     * @return
     */
    @PostMapping("add")
    public Object add(User user) {
        if (service.isExist(user)) {
            return ResultsUtils.fail(ResponseCodes.PARAMTER_ERROR, "登录名重复，请重新输入");
        }
        user.setCreateTime(new Date());
        user.setCreateName("Jeff");
        service.save(user);
        return ResultsUtils.success();
    }

    /**
     *
     * @description: 修改用户
     * @author: Jeff
     * @param user
     * @return
     */
    @PostMapping("update")
    public Object update(User user) {
        Validate.notNull(user.getId(), Constant.CHECK_MESSAGE, "用户id");
        if (service.isExist(user)) {
            return ResultsUtils.fail(ResponseCodes.PARAMTER_ERROR, "登录名重复，请重新输入");
        }
        user.setModifyTime(new Date());
        user.setModifyName("Jeff");
        service.updateById(user);
        return ResultsUtils.success();
    }

    /**
     *
     * @description: 删除用户
     * @author: Jeff
     * @param id
     * @return
     */
    @RequestMapping("delete")
    public Object delete(Long id) {
        Validate.notNull(id, Constant.CHECK_MESSAGE, "用户id");
        service.removeById(id);
        return ResultsUtils.success();
    }

    /**
     *
     * @description: 查看用户
     * @author: Jeff
     * @param id
     * @return
     */
    @RequestMapping("getById")
    public Object getById(Long id) {
        Validate.notNull(id, Constant.CHECK_MESSAGE, "用户id");
        return ResultsUtils.success(service.getById(id));
    }

    /**
     *
     * @description: 获取用户列表(分页)
     * @author: Jeff
     * @param page
     * @return
     */
    @RequestMapping("getList")
    public Object getList(PageEntity pageEntity, UserParam param) {
        Page<User> page = service.getList(pageEntity, param);
        return ResultsUtils.success(page.getRecords(), page.getTotal());
    }

}

创建MybatisPlus分页配置类MybatisPlusConfig

package com.jeff.mybatis.plus.config;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import com.baomidou.mybatisplus.extension.plugins.PaginationInterceptor;

/**
 *
 * @description: MybatisPlus分页配置类
 * @author: Jeff
 */
@Configuration
public class MybatisPlusConfig {

    @Bean
    public PaginationInterceptor paginationInterceptor() {
        return new PaginationInterceptor();
    }

}

打开浏览器访问 http://localhost:9001/user/getList?page=1&rows=5

原文地址：https://www.cnblogs.com/jiefu/p/12501434.html