src/main/java
└─ com.neuedu.hisweb
   ├── config
   │   └── MybatisPlusConfig.java     // 配置類（已提供）
   ├── controller
   │   └── UserController.java        // 控制器
   ├── entity
   │   └── User.java                  // 實(shí)體類
   ├── mapper
   │   └── UserMapper.java            // Mapper 接口
   ├── service
   │   ├── UserService.java           // Service 接口
   │   └── impl
   │       └── UserServiceImpl.java   // Service 實(shí)現(xiàn)
   └── HisWebApplication.java         // 啟動(dòng)類

package com.neuedu.hisweb.entity;
 
import com.baomidou.mybatisplus.annotation.TableId;
import com.baomidou.mybatisplus.annotation.TableName;
import lombok.Data;
 
@Data
@TableName("user")  // 對(duì)應(yīng)數(shù)據(jù)庫(kù)表名
public class User {
    @TableId  // 主鍵注解
    private Long id;
    private String username;
    private String password;
    private Integer age;
    private String email;
}

package com.neuedu.hisweb.mapper;
 
import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import com.neuedu.hisweb.entity.User;
import org.apache.ibatis.annotations.Mapper;
 
@Mapper
public interface UserMapper extends BaseMapper<User> {
    // 繼承 BaseMapper 后，自動(dòng)擁有 CRUD 方法
    // 無(wú)需編寫(xiě) selectById, insert, update, delete 等方法
}

package com.neuedu.hisweb.service;
 
import com.baomidou.mybatisplus.core.metadata.IPage;
import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import com.neuedu.hisweb.entity.User;
 
public interface UserService {
    // 分頁(yè)查詢用戶列表
    IPage<User> getUserPage(Page<User> page);
    
    // 條件分頁(yè)查詢
    IPage<User> getUserPageByCondition(Page<User> page, String username);
}

package com.neuedu.hisweb.service.impl;
 
import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.baomidou.mybatisplus.core.metadata.IPage;
import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.neuedu.hisweb.entity.User;
import com.neuedu.hisweb.mapper.UserMapper;
import com.neuedu.hisweb.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
 
@Service
public class UserServiceImpl extends ServiceImpl<UserMapper, User> implements UserService {
    
    @Autowired
    private UserMapper userMapper;
    
    // 分頁(yè)查詢所有用戶
    @Override
    public IPage<User> getUserPage(Page<User> page) {
        // Page 參數(shù)包含頁(yè)碼和每頁(yè)條數(shù)
        // 調(diào)用 BaseMapper 的 selectPage 方法，自動(dòng)生成分頁(yè) SQL
        return userMapper.selectPage(page, null);  // null 表示無(wú)查詢條件
    }
    
    // 條件分頁(yè)查詢
    @Override
    public IPage<User> getUserPageByCondition(Page<User> page, String username) {
        QueryWrapper<User> queryWrapper = new QueryWrapper<>();
        queryWrapper.like("username", username);  // 模糊查詢用戶名
        
        // 帶條件的分頁(yè)查詢
        return userMapper.selectPage(page, queryWrapper);
    }
}

package com.neuedu.hisweb.controller;
 
import com.baomidou.mybatisplus.core.metadata.IPage;
import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import com.neuedu.hisweb.entity.User;
import com.neuedu.hisweb.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;
 
@RestController
@RequestMapping("/api/users")
public class UserController {
    
    @Autowired
    private UserService userService;
    
    // 分頁(yè)查詢用戶列表
    @GetMapping("/page")
    public IPage<User> getUserPage(
            @RequestParam(defaultValue = "1") Integer pageNum,  // 頁(yè)碼，默認(rèn)第1頁(yè)
            @RequestParam(defaultValue = "10") Integer pageSize  // 每頁(yè)條數(shù)，默認(rèn)10條
    ) {
        // 創(chuàng)建分頁(yè)對(duì)象
        Page<User> page = new Page<>(pageNum, pageSize);
        
        // 調(diào)用 Service 方法進(jìn)行分頁(yè)查詢
        return userService.getUserPage(page);
    }
    
    // 條件分頁(yè)查詢
    @GetMapping("/page/condition")
    public IPage<User> getUserPageByCondition(
            @RequestParam(defaultValue = "1") Integer pageNum,
            @RequestParam(defaultValue = "10") Integer pageSize,
            @RequestParam(required = false) String username  // 可選參數(shù)：用戶名
    ) {
        Page<User> page = new Page<>(pageNum, pageSize);
        
        // 帶條件的分頁(yè)查詢
        return userService.getUserPageByCondition(page, username);
    }
}

package com.neuedu.hisweb.config;
 
import com.baomidou.mybatisplus.extension.plugins.MybatisPlusInterceptor;
import com.baomidou.mybatisplus.extension.plugins.inner.PaginationInnerInterceptor;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
 
/**
 * MyBatis-Plus 配置類
 */
@Configuration
public class MybatisPlusConfig {
 
    @Bean
    public MybatisPlusInterceptor mybatisPlusInterceptor() {
        // 創(chuàng)建 MyBatis-Plus 攔截器管理器
        MybatisPlusInterceptor interceptor = new MybatisPlusInterceptor();
        
        // 添加分頁(yè)插件
        interceptor.addInnerInterceptor(new PaginationInnerInterceptor());
        
        // 可以添加其他插件（如樂(lè)觀鎖、邏輯刪除等）
        // interceptor.addInnerInterceptor(new OptimisticLockerInnerInterceptor());
        
        return interceptor;
    }
}

package com.neuedu.hisweb;
 
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
 
@SpringBootApplication
@MapperScan("com.neuedu.hisweb.mapper")  // 掃描 Mapper 接口
public class HisWebApplication {
    public static void main(String[] args) {
        SpringApplication.run(HisWebApplication.class, args);
    }
}

GET http://localhost:8080/api/users/page?pageNum=1&pageSize=5 

GET http://localhost:8080/api/users/page/condition?pageNum=1&pageSize=5&username=張 

{
    "records": [ /* 當(dāng)前頁(yè)數(shù)據(jù) */ ],
    "total": 100,      // 總記錄數(shù)
    "size": 10,        // 每頁(yè)條數(shù)
    "current": 1,      // 當(dāng)前頁(yè)碼
    "pages": 10        // 總頁(yè)數(shù)
}

// 可自定義分頁(yè)插件參數(shù)
PaginationInnerInterceptor paginationInterceptor = new PaginationInnerInterceptor();
paginationInterceptor.setMaxLimit(1000L);  // 限制單頁(yè)最大條數(shù)
paginationInterceptor.setOverflow(false);  // 溢出總頁(yè)數(shù)后是否進(jìn)行處理
interceptor.addInnerInterceptor(paginationInterceptor);

paginationInterceptor.setDbType(DbType.MYSQL);