基于hibernate實(shí)現(xiàn)的分頁(yè)技術(shù)實(shí)例分析

更新時(shí)間：2016年03月24日 11:40:54 作者：beyond667

這篇文章主要介紹了基于hibernate實(shí)現(xiàn)的分頁(yè)技術(shù),結(jié)合實(shí)例形式分析了Hibernate分頁(yè)技術(shù)的原理,實(shí)現(xiàn)步驟與相關(guān)實(shí)現(xiàn)技巧,需要的朋友可以參考下

本文實(shí)例講述了基于hibernate實(shí)現(xiàn)的分頁(yè)技術(shù)。分享給大家供大家參考，具體如下：

先說(shuō)明一下基于hibernate實(shí)現(xiàn)分頁(yè)的原理，假如從數(shù)據(jù)庫(kù)取出100條數(shù)據(jù)，我們要讓每頁(yè)顯示10條，假如從30開始，只需要設(shè)置起始位置和最大的返回結(jié)果即可
先上代碼：注意傳進(jìn)來(lái)的參數(shù)有 Page這類，后面有介紹

public List<Article> queryByPage(final String username, final Page page) {
    return this.getHibernateTemplate().executeFind(new HibernateCallback() {
      public Object doInHibernate(Session session)
          throws HibernateException, SQLException {
        Query query = session.createQuery("select art from Article art where art.username = ?");
        //設(shè)置參數(shù)
        query.setParameter(0, username);
        //設(shè)置每頁(yè)顯示多少個(gè)，設(shè)置多大結(jié)果。
        query.setMaxResults(page.getEveryPage());
        //設(shè)置起點(diǎn)
        query.setFirstResult(page.getBeginIndex());
        return query.list();
      }
});

上面關(guān)鍵代碼是 setMaxResults(),和setFirstResult(),即設(shè)置最大顯示值和起點(diǎn)

這里我們需要一個(gè)Page工具類，用來(lái)操作分頁(yè)。

Page.java：

package com.fenye;
public class Page {
  // 1.每頁(yè)顯示數(shù)量(everyPage)
  private int everyPage;
  // 2.總記錄數(shù)(totalCount)
  private int totalCount;
  // 3.總頁(yè)數(shù)(totalPage)
  private int totalPage;
  // 4.當(dāng)前頁(yè)(currentPage)
  private int currentPage;
  // 5.起始點(diǎn)(beginIndex)
  private int beginIndex;
  // 6.是否有上一頁(yè)(hasPrePage)
  private boolean hasPrePage;
  // 7.是否有下一頁(yè)(hasNextPage)
  private boolean hasNextPage;
  public Page(int everyPage, int totalCount, int totalPage, int currentPage,
      int beginIndex, boolean hasPrePage, boolean hasNextPage) {
    this.everyPage = everyPage;
    this.totalCount = totalCount;
    this.totalPage = totalPage;
    this.currentPage = currentPage;
    this.beginIndex = beginIndex;
    this.hasPrePage = hasPrePage;
    this.hasNextPage = hasNextPage;
  }
  //構(gòu)造函數(shù)，默認(rèn)
  public Page(){}
  //構(gòu)造方法，對(duì)所有屬性進(jìn)行設(shè)置
  public int getEveryPage() {
    return everyPage;
  }
  public void setEveryPage(int everyPage) {
    this.everyPage = everyPage;
  }
  public int getTotalCount() {
    return totalCount;
  }
  public void setTotalCount(int totalCount) {
    this.totalCount = totalCount;
  }
  public int getTotalPage() {
    return totalPage;
  }
  public void setTotalPage(int totalPage) {
    this.totalPage = totalPage;
  }
  public int getCurrentPage() {
    return currentPage;
  }
  public void setCurrentPage(int currentPage) {
    this.currentPage = currentPage;
  }
  public int getBeginIndex() {
    return beginIndex;
  }
  public void setBeginIndex(int beginIndex) {
    this.beginIndex = beginIndex;
  }
  public boolean isHasPrePage() {
    return hasPrePage;
  }
  public void setHasPrePage(boolean hasPrePage) {
    this.hasPrePage = hasPrePage;
  }
  public boolean isHasNextPage() {
    return hasNextPage;
  }
  public void setHasNextPage(boolean hasNextPage) {
    this.hasNextPage = hasNextPage;
  }
}

Page工具類主要是封裝頁(yè)面信息，一共多少數(shù)據(jù)啊，一頁(yè)顯示多少啊，起點(diǎn)的序號(hào)，總頁(yè)數(shù)，是否有上一頁(yè)下一頁(yè)，當(dāng)前頁(yè)。

還需要一個(gè)操作page的工具類，PageUtil.java

package com.sanqing.fenye;
/*
 * 分頁(yè)信息輔助類
 */
public class PageUtil {
  public static Page createPage(int everyPage,int totalCount,int currentPage) {
    everyPage = getEveryPage(everyPage);
    currentPage = getCurrentPage(currentPage);
    int totalPage = getTotalPage(everyPage, totalCount);
    int beginIndex = getBeginIndex(everyPage, currentPage);
    boolean hasPrePage = getHasPrePage(currentPage);
    boolean hasNextPage = getHasNextPage(totalPage, currentPage);
    return new Page(everyPage, totalCount, totalPage, currentPage,
        beginIndex, hasPrePage, hasNextPage);
  }
  public static Page createPage(Page page,int totalCount) {
    int everyPage = getEveryPage(page.getEveryPage());
    int currentPage = getCurrentPage(page.getCurrentPage());
    int totalPage = getTotalPage(everyPage, totalCount);
    int beginIndex = getBeginIndex(everyPage, currentPage);
    boolean hasPrePage = getHasPrePage(currentPage);
    boolean hasNextPage = getHasNextPage(totalPage, currentPage);
    return new Page(everyPage, totalCount, totalPage, currentPage,
        beginIndex, hasPrePage, hasNextPage);
  }
  //設(shè)置每頁(yè)顯示記錄數(shù)
  public static int getEveryPage(int everyPage) {
    return everyPage == 0 ? 10 : everyPage;
  }
  //設(shè)置當(dāng)前頁(yè)
  public static int getCurrentPage(int currentPage) {
    return currentPage == 0 ? 1 : currentPage;
  }
  //設(shè)置總頁(yè)數(shù),需要總記錄數(shù)，每頁(yè)顯示多少
  public static int getTotalPage(int everyPage,int totalCount) {
    int totalPage = 0;
    if(totalCount % everyPage == 0) {
      totalPage = totalCount / everyPage;
    } else {
      totalPage = totalCount / everyPage + 1;
    }
    return totalPage;
  }
  //設(shè)置起始點(diǎn)，需要每頁(yè)顯示多少，當(dāng)前頁(yè)
  public static int getBeginIndex(int everyPage,int currentPage) {
    return (currentPage - 1) * everyPage;
  }
  //設(shè)置是否有上一頁(yè)，需要當(dāng)前頁(yè)
  public static boolean getHasPrePage(int currentPage) {
    return currentPage == 1 ? false : true;
  }
  //設(shè)置是否有下一個(gè)，需要總頁(yè)數(shù)和當(dāng)前頁(yè)
  public static boolean getHasNextPage(int totalPage, int currentPage) {
    return currentPage == totalPage || totalPage == 0 ? false : true;
  }
}

創(chuàng)建Page只需要3個(gè)參數(shù)，每頁(yè)顯示多少數(shù)據(jù)，當(dāng)前頁(yè)，總共多少數(shù)據(jù)，其他的4個(gè)參數(shù)都可以通過(guò)這三個(gè)計(jì)算出來(lái)

所以后面要?jiǎng)?chuàng)建Page，只需要調(diào)用這工具方法PageUtil.createPage(3個(gè)參數(shù))，就返回一Page.

返回的Page就是前面參數(shù)的Page，即要顯示的分頁(yè)

這樣就算完成了分頁(yè)的功能。

希望本文所述對(duì)大家基于Hibernate框架的Java程序設(shè)計(jì)有所幫助。

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