mybatis分页查询
1.分页的自定义实现（以采用ssm框架，前端使用layui的项目实现为例）
MenuMapper.xml中sql查询语句需要传入开始值和查询数量
MenuMapper.java
/**
* 获取总菜单个数
*
* @return
*/
int countMenu();
/**
* 获取所有菜单
*
* @param offset 开始值
* @param limit 查询数据数量
* @return
*/
ListPageBean.java列表数据封装，查询总数以及分页数据
import java.util.List;
/**
* 作用:分页数据
*/
public class PageBean {
private List data;
private int count;
public PageBean(List data, int count) {
this.data = data;
this.count = count;
}
public List getData() {
return data;
}
public void setData(List data) {
this.data = data;
}
public int getCount() {
return count;
}
public void setCount(int count) {
this.count = count;
}
}service接口略过，MenuServiceImpl.java将查询结果封装到PageBean中
public PageBean getMenuList(Integer page, Integer limit){
int offset = (page - 1) * limit;
ListLayuiResponseJSONBean.java和jsp的交互json封装
import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.serializer.SerializerFeature;
import com.springboot.first.domain.enums.ClientResponseStatusEnum;
/**
* 为LayUI
* Created by FENGCUIJIE on 2017/7/13.
*/
public class LayuiResponseJSONBean {
/**
* 错误消息
*/
private String msg;
/**
* 返回代码
*/
private String code;
/**
* 返回数据集合
*/
private Object data;
private int count;
public String getMsg() {
return msg;
}
public void setMsg(String msg) {
this.msg = msg;
}
public String getCode() {
return code;
}
public void setCode(String code) {
this.code = code;
}
public Object getData() {
return data;
}
public void setData(Object data) {
this.data = data;
}
public int getCount() {
return count;
}
public void setCount(int count) {
this.count = count;
}
public static LayuiResponseJSONBean getSuccessClientResponseJSONBean() {
LayuiResponseJSONBean clientResponseJSONBean = new LayuiResponseJSONBean();
clientResponseJSONBean.setCode("0");
clientResponseJSONBean.setMsg("");
return clientResponseJSONBean;
}
public static LayuiResponseJSONBean getFailedClientResponseJSONBean() {
LayuiResponseJSONBean clientResponseJSONBean = new LayuiResponseJSONBean();
clientResponseJSONBean.setCode(ClientResponseStatusEnum.CLIENT_RESPONSE_FAILED.getStatusCode());
clientResponseJSONBean.setMsg(ClientResponseStatusEnum.CLIENT_RESPONSE_FAILED.getMessage());
return clientResponseJSONBean;
}
public void setCodeAndMessage(ClientResponseStatusEnum enums) {
setCode(enums.getStatusCode());
setMsg(enums.getMessage());
}
public final String toJSONString() {
return JSON.toJSONString(this, SerializerFeature.WriteMapNullValue, SerializerFeature.DisableCircularReferenceDetect);
}
}ClientResponseStatusEnum.java
package com.xiaodou.hestia.entity.enums;
/**
* @author tao
*/
public enum ClientResponseStatusEnum {
CLIENT_RESPONSE_SUCCESS("SUCCESS", "成功"),
CLIENT_RESPONSE_FAILED("FAILED", "失败"),
public String getStatusCode() {
return statusCode;
}
public void setStatusCode(String statusCode) {
this.statusCode = statusCode;
}
public String getMessage() {
return message;
}
public void setMessage(String message) {
this.message = message;
}
private String statusCode;
private String message;
ClientResponseStatusEnum(String statusCode, String message) {
this.statusCode = statusCode;
this.message = message;
}
}MenuController.java
/**
* 分页获取菜单列表
*
* @param page 当前页
* @param limit 每页大小
* @return
*/
@RequestMapping(value = "/list", method = RequestMethod.GET, produces = MediaType.APPLICATION_JSON_VALUE + CHARSET)
@ResponseBody
public String listMenu(Integer page, Integer limit) {
LayuiResponseJSONBean layuiResponseJSONBean = new LayuiResponseJSONBean();
page = page == null ? 1 : page;
limit = limit == null ? 10 : limit;
try {
PageBean pageBean = menuServiceImpl.getMenuList(page, limit);
layuiResponseJSONBean = LayuiResponseJSONBean.getSuccessClientResponseJSONBean();
layuiResponseJSONBean.setData(pageBean.getData());
layuiResponseJSONBean.setCount(pageBean.getCount());
} catch (Exception e) {
e.printStackTrace();
layuiResponseJSONBean = LayuiResponseJSONBean.getFailedClientResponseJSONBean();
logger.error("获取菜单列表失败：" + e.getMessage());
}
return JSONObject.toJSONString(layuiResponseJSONBean);
}menu.jsp
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
菜单管理
序号
菜单名称
菜单路径
菜单图标
父级菜单
菜单描述
创建时间
更新时间
操作
2.通过分页插件的实现:Mybatis-Plus（本例为springboot项目，前端依然使用layui）
Mybatis-Plus（简称MP）是一个 Mybatis 的增强工具，在 Mybatis 的基础上只做增强不做改变，为简化开发、提高效率而生。
添加Mybatis-Plus的maven依赖
com.baomidou
mybatis-plus
2.1.9
spring注入mybatis配置分页插件 MybatisPlusConfig.java
import com.baomidou.mybatisplus.plugins.PaginationInterceptor;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.transaction.annotation.EnableTransactionManagement;
@EnableTransactionManagement
@Configuration
@MapperScan("com.springboot.first.mapper.*")
public class MybatisPlusConfig {
/**
* 分页插件
*/
@Bean
public PaginationInterceptor paginationInterceptor() {
return new PaginationInterceptor();
}
}UserMapper.xml中按照全部查询方式检索即可
UserMapper.java中参数为Pageination
ListUserServiceImpl.java调用翻页方法，需要page.setRecords回传给页面
public PageUserController.java中获取分页后的数据
@RequestMapping("/toUserList")
public String toUserList(){
return "userList";
} @RequestMapping("/getUserList")
@ResponseBody
public String getUserList(Integer page,Integer limit){
LayuiResponseJSONBean layuiResponseJSONBean;
page = page == null ? 1 : page;
limit = limit == null ? 10 : limit;
Page pages = new Page(page,limit);
PageuserList.jsp
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
用户列表
序号
登陆名
密码
用户昵称
年龄
性别
请求列表：
控制台打印sql如下：
