SpringBoot集成MyBatis的分頁插件PageHelper實例代碼

<!-- mybatis的分頁插件 -->
 <dependency>
   <groupId>com.github.pagehelper</groupId>
   <artifactId>pagehelper</artifactId>
 </dependency>

<?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>
  <!-- 【mybatis的核心配置文件】 -->
  <!-- 批量設置別名(可以不配) 作用：就是在mapper.xml文件中直接寫類名，也可以不用寫全路徑名。 -->
  <typeAliases>
    <package name="cn.e3mall.manager.po" />
  </typeAliases>
  <!-- 配置mybatis的分頁插件PageHelper -->
  <plugins>
    <!-- com.github.pagehelper為PageHelper類所在包名 -->
    <plugin interceptor="com.github.pagehelper.PageHelper">
      <!-- 設置數(shù)據庫類型Oracle,MySQL,MariaDB,SQLite,Hsqldb,PostgreSQL六種數(shù)據庫 -->
      <property name="dialect" value="mysql"/>
    </plugin>
  </plugins>
</configuration>

//分頁查詢商品列表：
  @Override
  public DatagridResult itemList(Integer page, Integer rows) {
    //為了程序的嚴謹性，判斷非空：
    if(page == null){
      page = 1;  //設置默認當前頁
    }
    if(page <= 0){
      page = 1;
    }
    if(rows == null){
      rows = 30;  //設置默認每頁顯示的商品數(shù)(因為jsp頁面上默認寫的就是30條)
    }
    //1、設置分頁信息，包括當前頁數(shù)和每頁顯示的總計數(shù)
    PageHelper.startPage(page, rows);
    //2、執(zhí)行查詢
    TbItemExample example = new TbItemExample();
    List<TbItem> list = tbItemMapper.selectByExample(example);
    //3、獲取分頁查詢后的數(shù)據
    PageInfo<TbItem> pageInfo = new PageInfo<>(list);
    //4、封裝需要返回的分頁實體
    DatagridResult result = new DatagridResult();
    //設置獲取到的總記錄數(shù)total：
    result.setTotal(pageInfo.getTotal());
    //設置數(shù)據集合rows：
    result.setRows(list);
    return result;
  }

<dependency>
   <groupId>com.github.pagehelper</groupId>
   <artifactId>pagehelper</artifactId>
   <version>4.1.6</version>
 </dependency>

//配置mybatis的分頁插件pageHelper
  @Bean
  public PageHelper pageHelper(){
    PageHelper pageHelper = new PageHelper();
    Properties properties = new Properties();
    properties.setProperty("offsetAsPageNum","true");
    properties.setProperty("rowBoundsWithCount","true");
    properties.setProperty("reasonable","true");
    properties.setProperty("dialect","mysql");  //配置mysql數(shù)據庫的方言
    pageHelper.setProperties(properties);
    return pageHelper;
  }

package com.zxz.utils;
/**
 * 分頁bean
 */
import java.util.List;
public class PageBean<T> {
  // 當前頁
  private Integer currentPage = 1;
  // 每頁顯示的總條數(shù)
  private Integer pageSize = 10;
  // 總條數(shù)
  private Integer totalNum;
  // 是否有下一頁
  private Integer isMore;
  // 總頁數(shù)
  private Integer totalPage;
  // 開始索引
  private Integer startIndex;
  // 分頁結果
  private List<T> items;
  public PageBean() {
    super();
  }
  public PageBean(Integer currentPage, Integer pageSize, Integer totalNum) {
    super();
    this.currentPage = currentPage;
    this.pageSize = pageSize;
    this.totalNum = totalNum;
    this.totalPage = (this.totalNum+this.pageSize-1)/this.pageSize;
    this.startIndex = (this.currentPage-1)*this.pageSize;
    this.isMore = this.currentPage >= this.totalPage?0:1;
  }
  public Integer getCurrentPage() {
    return currentPage;
  }
  public void setCurrentPage(Integer currentPage) {
    this.currentPage = currentPage;
  }
  public Integer getPageSize() {
    return pageSize;
  }
  public void setPageSize(Integer pageSize) {
    this.pageSize = pageSize;
  }
  public Integer getTotalNum() {
    return totalNum;
  }
  public void setTotalNum(Integer totalNum) {
    this.totalNum = totalNum;
  }
  public Integer getIsMore() {
    return isMore;
  }
  public void setIsMore(Integer isMore) {
    this.isMore = isMore;
  }
  public Integer getTotalPage() {
    return totalPage;
  }
  public void setTotalPage(Integer totalPage) {
    this.totalPage = totalPage;
  }
  public Integer getStartIndex() {
    return startIndex;
  }
  public void setStartIndex(Integer startIndex) {
    this.startIndex = startIndex;
  }
  public List<T> getItems() {
    return items;
  }
  public void setItems(List<T> items) {
    this.items = items;
  }
}

@Override
  public List<Item> findItemByPage(int currentPage,int pageSize) {
    //設置分頁信息，分別是當前頁數(shù)和每頁顯示的總記錄數(shù)【記?。罕仨氃趍apper接口中的方法執(zhí)行之前設置該分頁信息】
    PageHelper.startPage(currentPage, pageSize);
    List<Item> allItems = itemMapper.findAll();    //全部商品
    int countNums = itemMapper.countItem();      //總記錄數(shù)
    PageBean<Item> pageData = new PageBean<>(currentPage, pageSize, countNums);
    pageData.setItems(allItems);
    return pageData.getItems();
  }
/**
   * 商品分頁功能(集成mybatis的分頁插件pageHelper實現(xiàn))
   * 
   * @param currentPage  :當前頁數(shù)
   * @param pageSize    :每頁顯示的總記錄數(shù)
   * @return
   */
  @RequestMapping("/itemsPage")
  @ResponseBody
  public List<Item> itemsPage(int currentPage,int pageSize){
    return itemService.findItemByPage(currentPage, pageSize);
  }