Mybatis分页插件PageHelper配置及使用方法详解

环境

框架：spring+springmvc+mybatis

pom.xml

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									<!-- 引入mybatis的 pagehelper 分页插件 -->

									    <dependency>

									      <groupId>com.github.pagehelper</groupId>

									      <artifactId>pagehelper</artifactId>

									      <version>5.1.2</version>

									    </dependency>

配置全局配置文件

在mybatis的全局配置文件中配置PageHelper分页插件

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									<?xml version="1.0" encoding="UTF-8"?>

									<!DOCTYPE configuration

									PUBLIC "-//mybatis.org//DTD Config 3.0//EN"

									"http://mybatis.org/dtd/mybatis-3-config.dtd">

									<configuration>

									  <!-- 引入 pageHelper插件 -->

									  <!--注意这里要写成PageInterceptor, 5.0之前的版本都是写PageHelper, 5.0之后要换成PageInterceptor-->

									  <plugins>

									    <plugin interceptor="com.github.pagehelper.PageInterceptor">

									      <!--reasonable：分页合理化参数，默认值为false,直接根据参数进行查询。

									       当该参数设置为 true 时，pageNum<=0 时会查询第一页， pageNum>pages（超过总数时），会查询最后一页。-->

									      <!--<property name="reasonable" value="true"/>-->

									    </plugin>

									  </plugins>

									</configuration>

使用

例如：实现对用户的多条件查询

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									package com.szfore.model;

									import java.util.Date;

									import java.util.List;

									public class User {

									    private Integer id;

									    private String uname;

									    private String pwd;

									    private String name;

									    private Integer sex;

									    private String phone;

									    private String company;

									    private String jobtitle;

									    private String birth;

									    private Date createdate;

									    private Date lastlogintime;

									    private List<Role> roleList;

									    public List<Role> getRoleList() {

									        return roleList;

									    }

									    public void setRoleList(List<Role> roleList) {

									        this.roleList = roleList;

									    }

									    public Integer getId() {

									        return id;

									    }

									    public void setId(Integer id) {

									        this.id = id;

									    }

									    public String getUname() {

									        return uname;

									    }

									    public void setUname(String uname) {

									        this.uname = uname == null ? null : uname.trim();

									    }

									    public String getPwd() {

									        return pwd;

									    }

									    public void setPwd(String pwd) {

									        this.pwd = pwd == null ? null : pwd.trim();

									    }

									    public String getName() {

									        return name;

									    }

									    public void setName(String name) {

									        this.name = name == null ? null : name.trim();

									    }

									    public Integer getSex() {

									        return sex;

									    }

									    public void setSex(Integer sex) {

									        this.sex = sex;

									    }

									    public String getPhone() {

									        return phone;

									    }

									    public void setPhone(String phone) {

									        this.phone = phone == null ? null : phone.trim();

									    }

									    public String getCompany() {

									        return company;

									    }

									    public void setCompany(String company) {

									        this.company = company == null ? null : company.trim();

									    }

									    public String getJobtitle() {

									        return jobtitle;

									    }

									    public void setJobtitle(String jobtitle) {

									        this.jobtitle = jobtitle == null ? null : jobtitle.trim();

									    }

									    public String getBirth() {

									        return birth;

									    }

									    public void setBirth(String birth) {

									        this.birth = birth == null ? null : birth.trim();

									    }

									    public Date getCreatedate() {

									        return createdate;

									    }

									    public void setCreatedate(Date createdate) {

									        this.createdate = createdate;

									    }

									    public Date getLastlogintime() {

									        return lastlogintime;

									    }

									    public void setLastlogintime(Date lastlogintime) {

									        this.lastlogintime = lastlogintime;

									    }

									}

UserMapper

注意：mapper中就按不分页的那种写法就好

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									package com.szfore.dao;

									import com.szfore.model.User;

									import com.szfore.model.UserExample;

									import java.util.List;

									import org.apache.ibatis.annotations.Param;

									import org.springframework.stereotype.Repository;

									@Repository

									public interface UserMapper {

									  /**

									   * 多条件分页查询

									   * @param userParam

									   * @return

									   */

									  public List<User> queryByPage(User userParam);

									}

UserMapper.xml

注意：sql中就不要写limit了，pageHelp会自己处理，sql就按不分页的那种写法就好

				?

									<!--多条件分页查询用户-->

									 <select id="queryByPage" resultType="com.szfore.model.User">

									  SELECT

									     *

									  FROM

									    `user` 

									  <WHERE>

									     <if test="id != null and id != ''">

									     AND id = #{id}

									    </if>

									    <if test="uname != null and uname != ''">

									     AND uname = #{uname}

									    </if>

									    <if test="name != null and name != ''">

									     AND name like '%${name}%'

									    </if>

									    <if test="phone != null and phone != ''">

									     AND phone like '%${phone}%'

									    </if>

									    <if test="company != null and company != ''">

									     AND company like '%${company}%'

									    </if>

									    <if test="jobtitle != null and jobtitle != ''">

									     AND jobTitle like '%${jobtitle}%'

									    </if>

									    <if test="birth != null and birth != ''">

									     AND birth like '%${birth}%'

									    </if>　　</WHERE>

									 </select>

UserServiceImpl

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									package com.szfore.service.impl;

									import com.github.pagehelper.PageHelper;

									import com.github.pagehelper.PageInfo;

									import com.szfore.dao.MenuMapper;

									import com.szfore.dao.UserMapper;

									import com.szfore.dao.UserRoleMapper;

									import com.szfore.model.*;

									import com.szfore.service.IUserService;

									import org.springframework.beans.factory.annotation.Autowired;

									import org.springframework.stereotype.Service;

									import org.springframework.transaction.annotation.Transactional;

									import javax.servlet.http.HttpSession;

									import java.util.Date;

									import java.util.HashMap;

									import java.util.List;

									import java.util.Map;

									@Service

									public class UserServiceImpl implements IUserService{

									  @Autowired

									  private UserMapper userMapper;

									  @Autowired

									  private MenuMapper menuMapper;

									  @Autowired

									  private UserRoleMapper userRoleMapper;

									  /**

									   * 多条件分页查询用户

									   * @param userParam

									   * @param pageNum

									   * @param pageSize

									   * @return

									   */

									  public Json queryByPage(User userParam,Integer pageNum,Integer pageSize) {

									    //利用PageHelper分页查询 注意：这个一定要放查询语句的前一行,否则无法进行分页,因为它对紧随其后第一个sql语句有效

									    PageHelper.startPage(pageNum, pageSize);

									    List<User> userList = userMapper.queryByPage(userParam);

									    PageInfo<User> pageInfo = new PageInfo<User>(userList);

									    Json json = new Json();

									    json.setMsg("成功！");

									    json.setObj(pageInfo);

									    json.setSuccess(true);

									    return json;

									  }

									}

说明：PageInfo是PageHelper自带的分页对象类，详情如下：

当前页
private int pageNum;
每页的数量
private int pageSize;
当前页的数量
private int size;
//由于startRow和endRow不常用，这里说个具体的用法
//可以在页面中"显示startRow到endRow 共size条数据"

当前页面第一个元素在数据库中的行号
private int startRow;
当前页面最后一个元素在数据库中的行号
private int endRow;
总记录数
private long total;
总页数
private int pages;
结果集
private List<T> list;

第一页
private int firstPage;
前一页
private int prePage;

是否为第一页
private boolean isFirstPage = false;
是否为最后一页
private boolean isLastPage = false;
是否有前一页
private boolean hasPreviousPage = false;
是否有下一页
private boolean hasNextPage = false;
导航页码数
private int navigatePages;
所有导航页号
private int[] navigatepageNums;

通过PageInfo获取其他信息

PageHelper.startPage(req.getCurrentPage(), req.getPageSize(), true);
List<SecurityRiskLibary> list=securityRiskLibaryDAO.queryList(srl);
PageInfo page=new PageInfo(list);
page.getTotal();
page.xxxx

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持服务器之家。

原文链接：https://www.cnblogs.com/chenyanbin/p/13416870.html

Mybatis分页插件PageHelper配置及使用方法详解

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