MyBatis-Plus分页插件使用，自带分页及xml分页的使用

项目结构

配置文件

import com.baomidou.mybatisplus.extension.plugins.PaginationInterceptor;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

/**
 * @author miemie
 * @since 2018-08-10
 */
@Configuration
@MapperScan("com.example.demo.fr.mapper")
public class MybatisPlusConfig {

    /**
     * 分页插件
     */
    @Bean
    public PaginationInterceptor paginationInterceptor() {
        return new PaginationInterceptor();
    }
}

• UserMapper.java 方法内容

  import com.baomidou.mybatisplus.core.metadata.IPage;
  import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
  import com.example.demo.fr.entity.User;
  import com.baomidou.mybatisplus.core.mapper.BaseMapper;
  import com.example.demo.fr.model.MyPage;
  import com.example.demo.fr.model.ParamSome;
  import org.apache.ibatis.annotations.Param;
  
  /**
   * 
  
   *  Mapper 接口
   * 
   *
   * @author fr
   * @since 2019-01-24
   */
  public interface UserMapper extends BaseMapper {
  
      /**
       * 
  
       * 查询 : 根据state状态查询用户列表，分页显示
       * 注意!!: 如果入参是有多个,需要加注解指定参数名才能在xml中取值
       * 
       *
       * @param page 分页对象,xml中可以从里面进行取值,传递参数 Page 即自动分页,必须放在第一位(你可以继承Page实现自己的分页对象)
       * @return 分页对象
       */
      public IPage selectPageVo(Page page);
  
  }

  UserService.java 方法内容

  import com.baomidou.mybatisplus.core.metadata.IPage;
  import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
  import com.example.demo.fr.entity.User;
  import com.baomidou.mybatisplus.extension.service.IService;
  import org.springframework.stereotype.Service;
  
  import java.util.List;
  
  /**
   * 
  
   *  服务类
   * 
   *
   * @author fr
   * @since 2019-01-24
   */
  public interface UserService extends IService {
      public IPage selectUserPage(Page page);
  }
  

  UserServiceImpl.java 方法内容

  import com.baomidou.mybatisplus.core.metadata.IPage;
  import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
  import com.example.demo.fr.entity.User;
  import com.example.demo.fr.mapper.UserMapper;
  import com.example.demo.fr.service.UserService;
  import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
  import org.springframework.beans.factory.annotation.Autowired;
  import org.springframework.stereotype.Service;
  
  /**
   * 
  
   *  服务实现类
   * 
   *
   * @author fr
   * @since 2019-01-24
   */
  @Service
  public class UserServiceImpl extends ServiceImpl implements UserService {
      @Autowired
      private UserMapper userMapper;
      @Override
      public IPage selectUserPage(Page page) {
          // 不进行 count sql 优化，解决 MP 无法自动优化 SQL 问题，这时候你需要自己查询 count 部分
          // page.setOptimizeCountSql(false);
          // 当 total 为非 0 时(默认为 0),分页插件不会进行 count 查询
          // 要点!! 分页返回的对象与传入的对象是同一个
          return userMapper.selectPageVo(page);
      }
  }

  分页使用model类

• import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
  import lombok.Data;
  import lombok.EqualsAndHashCode;
  import lombok.experimental.Accessors;
  
  /**
   * @author miemie
   * @since 2018-08-10
   */
  @Data
  @Accessors(chain = true)
  @EqualsAndHashCode(callSuper = true)
  public class MyPage extends Page {
      private static final long serialVersionUID = 5194933845448697148L;
  
      private Integer selectInt;
      private String selectStr;
  
      public MyPage(long current, long size) {
          super(current, size);
      }
  }

  package com.example.demo.fr.model;
  
  import lombok.AllArgsConstructor;
  import lombok.Data;
  import lombok.NoArgsConstructor;
  
  /**
   * @author miemie
   * @since 2018-09-20
   */
  @Data
  @NoArgsConstructor
  @AllArgsConstructor
  public class ParamSome {
  
      private Integer yihao;
      private String erhao;
  }
  

  Controller层测试类

• import com.alibaba.fastjson.JSON;
  import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper;
  import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
  import com.baomidou.mybatisplus.core.conditions.update.UpdateWrapper;
  import com.baomidou.mybatisplus.core.metadata.IPage;
  import com.baomidou.mybatisplus.core.toolkit.CollectionUtils;
  import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
  import com.example.demo.fr.entity.User;
  import com.example.demo.fr.mapper.UserMapper;
  import com.example.demo.fr.model.MyPage;
  import com.example.demo.fr.model.ParamSome;
  import com.example.demo.fr.service.UserService;
  import ikidou.reflect.TypeBuilder;
  import org.springframework.beans.factory.annotation.Autowired;
  import org.springframework.web.bind.annotation.PostMapping;
  import org.springframework.web.bind.annotation.RequestMapping;
  
  import org.springframework.web.bind.annotation.RestController;
  
  import java.util.List;
  
  /**
   * 
  
   *  前端控制器
   * 
   *
   * @author fr
   * @since 2019-01-24
   */
  @RestController
  @RequestMapping("/fr/user")
  public class UserController {
      @Autowired
      private UserMapper userMapper;
      @Autowired
      private UserService userService;
   
      @PostMapping("/page")
      public void tes1t1s11() {
          System.out.println("----- baseMapper 自带分页 ------");
          Page page = new Page<>(1, 5);
          IPage userIPage = userMapper.selectPage(page, new QueryWrapper());
  //        Assert.assertSame(page, userIPage);
          System.out.println("总条数 ------> " + userIPage.getTotal());
          System.out.println("当前页数 ------> " + userIPage.getCurrent());
          System.out.println("当前每页显示数 ------> " + userIPage.getSize());
          print(userIPage.getRecords());
          System.out.println("----- baseMapper 自带分页 ------");
  
          System.out.println("json 正反序列化 begin");
          String json = JSON.toJSONString(page);
          Page page1 = JSON.parseObject(json, TypeBuilder.newInstance(Page.class).addTypeParam(User.class).build());
          print(page1.getRecords());
          System.out.println("json 正反序列化 end");
  
          System.out.println("----- 自定义 XML 分页 ------");
          MyPage myPage = new MyPage(1, 5).setSelectInt(20).setSelectStr("Jack");
          ParamSome paramSome = new ParamSome(20, "Jack");
          IPage userMyPage = userService.selectUserPage(myPage);
          System.out.println("总条数 ------> " + userMyPage.getTotal());
          System.out.println("当前页数 ------> " + userMyPage.getCurrent());
          System.out.println("当前每页显示数 ------> " + userMyPage.getSize());
          print(userMyPage.getRecords());
          System.out.println("----- 自定义 XML 分页 ------");
      }
      private  void print(List list) {
          if (!CollectionUtils.isEmpty(list)) {
              list.forEach(System.out::println);
          }
      }
  }
  

  xml

• 
  
  
      
           SELECT *  FROM user
      
  
  

  数据库表结构及数据

• /*
  Navicat MySQL Data Transfer
  
  Source Server         : 47.98.144.196
  Source Server Version : 50724
  Source Host           : 47.98.144.196:3306
  Source Database       : test
  
  Target Server Type    : MYSQL
  Target Server Version : 50724
  File Encoding         : 65001
  
  Date: 2019-01-31 17:13:30
  */
  
  SET FOREIGN_KEY_CHECKS=0;
  
  -- ----------------------------
  -- Table structure for role
  -- ----------------------------
  DROP TABLE IF EXISTS `role`;
  CREATE TABLE `role` (
    `id` bigint(20) NOT NULL,
    `roleName` varchar(255) DEFAULT NULL,
    `roleDescribe` varchar(255) DEFAULT NULL,
    PRIMARY KEY (`id`)
  ) ENGINE=InnoDB DEFAULT CHARSET=utf8;
  
  -- ----------------------------
  -- Records of role
  -- ----------------------------
  INSERT INTO `role` VALUES ('1', '1', '1');
  INSERT INTO `role` VALUES ('2', '2', '2');
  INSERT INTO `role` VALUES ('3', '3', '3');
  INSERT INTO `role` VALUES ('4', '4', '4');
  
  -- ----------------------------
  -- Table structure for test
  -- ----------------------------
  DROP TABLE IF EXISTS `test`;
  CREATE TABLE `test` (
    `id` int(15) NOT NULL,
    `name` varchar(255) DEFAULT NULL,
    `tel` varchar(255) DEFAULT NULL,
    `sex` varchar(255) DEFAULT NULL,
    PRIMARY KEY (`id`)
  ) ENGINE=InnoDB DEFAULT CHARSET=utf8;
  
  -- ----------------------------
  -- Records of test
  -- ----------------------------
  INSERT INTO `test` VALUES ('1', '2', '3', '4');
  
  -- ----------------------------
  -- Table structure for user
  -- ----------------------------
  DROP TABLE IF EXISTS `user`;
  CREATE TABLE `user` (
    `id` bigint(50) NOT NULL AUTO_INCREMENT COMMENT '主键ID',
    `name` varchar(30) DEFAULT '' COMMENT '姓名',
    `age` int(11) DEFAULT NULL COMMENT '年龄',
    `email` varchar(50) DEFAULT NULL COMMENT '邮箱',
    `role_id` bigint(50) DEFAULT NULL,
    PRIMARY KEY (`id`)
  ) ENGINE=InnoDB AUTO_INCREMENT=20 DEFAULT CHARSET=utf8;
  
  -- ----------------------------
  -- Records of user
  -- ----------------------------
  INSERT INTO `user` VALUES ('1', 'mp', '3', '[email protected]', '1');
  INSERT INTO `user` VALUES ('2', 'Jack', '20', '[email protected]', '2');
  INSERT INTO `user` VALUES ('3', 'Tom', '28', '[email protected]', '3');
  INSERT INTO `user` VALUES ('4', 'Sandy', '21', null, '4');
  INSERT INTO `user` VALUES ('5', 'Billie', '24', '[email protected]', '1');
  INSERT INTO `user` VALUES ('6', 'Jone', '18', '[email protected]', '2');
  INSERT INTO `user` VALUES ('7', 'Jack', '20', '[email protected]', '3');
  INSERT INTO `user` VALUES ('8', 'Tom', '28', '[email protected]', '4');
  INSERT INTO `user` VALUES ('9', 'Sandy', '21', '[email protected]', '1');
  INSERT INTO `user` VALUES ('10', 'Billie', '24', '[email protected]', '2');
  INSERT INTO `user` VALUES ('11', 'Jone', '18', '[email protected]', '3');
  INSERT INTO `user` VALUES ('12', 'Jack', '20', '[email protected]', '4');
  INSERT INTO `user` VALUES ('13', 'Tom', '28', '[email protected]', '1');
  INSERT INTO `user` VALUES ('14', 'Sandy', '21', '[email protected]', '2');
  INSERT INTO `user` VALUES ('15', 'Billie', '24', '[email protected]', '3');
  INSERT INTO `user` VALUES ('19', '小羊', '3', '[email protected]', '4');
  

   

• 参考：https://mp.baomidou.com/guide/page.html

• 项目源码：https://pan.baidu.com/s/1tNkDVpvD493TNLn1WqXlUg

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