分页实例

最新推荐文章于 2025-08-07 22:41:04 发布

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分页每个项目里面差不多都会用到
我以前耶找了很多个但最近掌握了一个很好用的分页

分页由两个部分组成:

1 分页导航信息:

2 每个页面的数据查询语句信息:

所以为了实现上面两个功能,我们需要知道的信息是:

1 所查询的总记录数: recordCount;

2 每页所显示的记录数:pageSize

3 当前页号：pageIndex.

4 总共有多少页：pageCount.这个是分页内部的一个属性，可以由pageSize / pageSize +1来获得。

（）

先是一个page的bean：
package com.leatherstore.other;

public class Page {

/** 是否有上一页 */
private boolean hasPrePage;

/** 是否有下一页 */
private boolean hasNextPage;

/** 每页的数量 */
private int everyPage;

/** 总页数 */
private int totalPage;

/** 当前页*/
private int currentPage;

/** 起始点 */
private int beginIndex;

/** 总记录数*/
private int totalCount;

/**
* @return totalCount
*/
public int getTotalCount() {
return totalCount;
}

/**
* @param totalCount 要设置的 totalCount
*/
public void setTotalCount(int totalCount) {
this.totalCount = totalCount;
}

/** The default constructor */
public Page(){

}

/** construct the page by everyPage
* @param everyPage
* */
public Page(int everyPage){
this.everyPage = everyPage;
}

/** The whole constructor */
public Page(boolean hasPrePage, boolean hasNextPage,
int everyPage, int totalPage,
int currentPage, int beginIndex,int totalCount) {
this.hasPrePage = hasPrePage;
this.hasNextPage = hasNextPage;
this.everyPage = everyPage;
this.totalPage = totalPage;
this.currentPage = currentPage;
this.beginIndex = beginIndex;
this.totalCount = totalCount;
}

/**
* @return
* Returns the beginIndex.
*/
public int getBeginIndex() {
return beginIndex;
}

/**
* @param beginIndex
* The beginIndex to set.
*/
public void setBeginIndex(int beginIndex) {
this.beginIndex = beginIndex;
}

/**
* @return
* Returns the currentPage.
*/
public int getCurrentPage() {
return currentPage;
}

/**
* @param currentPage
* The currentPage to set.
*/
public void setCurrentPage(int currentPage) {
this.currentPage = currentPage;
}

/**
* @return
* Returns the everyPage.
*/
public int getEveryPage() {
return everyPage;
}

/**
* @param everyPage
* The everyPage to set.
*/
public void setEveryPage(int everyPage) {
this.everyPage = everyPage;
}

/**
* @return
* Returns the hasNextPage.
*/
public boolean getHasNextPage() {
return hasNextPage;
}

/**
* @param hasNextPage
* The hasNextPage to set.
*/
public void setHasNextPage(boolean hasNextPage) {
this.hasNextPage = hasNextPage;
}

/**
* @return
* Returns the hasPrePage.
*/
public boolean getHasPrePage() {
return hasPrePage;
}

/**
* @param hasPrePage
* The hasPrePage to set.
*/
public void setHasPrePage(boolean hasPrePage) {
this.hasPrePage = hasPrePage;
}

/**
* @return Returns the totalPage.
*
*/
public int getTotalPage() {
return totalPage;
}

/**
* @param totalPage
* The totalPage to set.
*/
public void setTotalPage(int totalPage) {
this.totalPage = totalPage;
}
}
然后构建一个page的工厂PageUtil：
package com.leatherstore.other;

public class PageUtil {
/**
* Use the origin page to create a new page
*
* @param page
* @param totalRecords
* @return
*/
public static Page createPage(Page page, int totalRecords) {
return createPage(page.getEveryPage(), page.getCurrentPage(),
totalRecords);
}

/**
* the basic page utils not including exception handler
*
* @param everyPage
* @param currentPage
* @param totalRecords
* @return page
*/
public static Page createPage(int everyPage, int currentPage,
int totalRecords) {
everyPage = getEveryPage(everyPage);
currentPage = getCurrentPage(currentPage);
int beginIndex = getBeginIndex(everyPage, currentPage);
int totalPage = getTotalPage(everyPage, totalRecords);
boolean hasNextPage = hasNextPage(currentPage, totalPage);
boolean hasPrePage = hasPrePage(currentPage);

return new Page(hasPrePage, hasNextPage, everyPage, totalPage,
currentPage, beginIndex, totalRecords);
}

private static int getEveryPage(int everyPage) {
return everyPage == 0 ? 10 : everyPage;
}

private static int getCurrentPage(int currentPage) {
return currentPage == 0 ? 1 : currentPage;
}

private static int getBeginIndex(int everyPage, int currentPage) {
return (currentPage - 1) * everyPage;
}

private static int getTotalPage(int everyPage, int totalRecords) {
int totalPage = 0;

if (totalRecords % everyPage == 0)
totalPage = totalRecords / everyPage;
else
totalPage = totalRecords / everyPage + 1;

return totalPage;
}

private static boolean hasPrePage(int currentPage) {
return currentPage == 1 ? false : true;
}

private static boolean hasNextPage(int currentPage, int totalPage) {
return currentPage == totalPage || totalPage == 0 ? false : true;
}

}
然后建一个专用的bean：
package com.leatherstore.hibernate.domain;

import java.util.List;

import com.leatherstore.other.Page;

public class Result {
private Page page; //分页信息
private List content; //每页显示的集合
/**
* The default constructor
*/
public Result() {
super();
}

/**
* The constructor using fields
*
* @param page
* @param content
*/
public Result(Page page, List content) {
this.page = page;
this.content = content;
}

/**
* @return Returns the content.
*/
public List getContent() {
return content;
}

/**
* @return Returns the page.
*/
public Page getPage() {
return page;
}

/**
* @param content
* The content to set.
*/
public void setContent(List content) {
this.content = content;
}

/**
* @param page
* The page to set.
*/
public void setPage(Page page) {
this.page = page;
}
}

然后在数据访问层写两个方法：
ProductDAO：
public List getProductByPage(Page page);
public int getProductCount(); //返回数据的总数
ProductDAO的接口实现ProductDAOImpl：
//为了在spring里统一编程风格：我用的回调的方法
public List getProductByPage(final Page page) {
return this.getHibernateTemplate().executeFind(new HibernateCallback(){
public Object doInHibernate(Session session) throws HibernateException, SQLException {
Query query=session.createQuery("from Productinfo");
query.setFirstResult(page.getBeginIndex()); //hibernate分页的精髓呵呵
query.setMaxResults(page.getEveryPage());
return query.list();
}
});
}

public int getProductCount() {
List list=this.getHibernateTemplate().find("select count(*) from Productinfo");
return ((Integer)list.iterator().next()).intValue();
}
然后是业务层：
IProduct：
public Result listProduct(Page page);
然后IProduct接口的实现：IProductImpl：
private ProductDAO productDAO;
public void setProductDAO(ProductDAO productDAO){
this.productDAO=productDAO;
}

public Result listProduct(Page page) {
int totalRecords = this.productDAO.getProductCount();
page = PageUtil.createPage(page, totalRecords);
List products = this.productDAO.getProductByPage(page);
return new Result(page, products);
}
然后再代理层：
ProductProxy：
IProduct pro=(IProduct)AppContext.getInstance().getappcontext().getBean("productServicewithTran");

public Result productlist(Page page){
try{
return pro.listProduct(page);
}catch(DataAccessException ex){
ex.printStackTrace();
return null;
}
}
呵呵终于到productAction啦
显示前方法的代码
Page page = new Page(); //实例化一个page对象
page.setEveryPage(10); //设置每页显示的条数
page.setCurrentPage(1); //为第一页
Result result = pdp.productlist(page);
request.setAttribute("page", pageinfo);
request.setAttribute("productlist", list);
return mapping.findForward("showProduct");
接着就是jsp页面了
<logic:iterate id="product" name="productlist">
//中间迭代所要显示的数据
</logic:iterate>
<tr>
<td width="80" height="30"> </td>
<logic:equal value="true" name="page" property="hasPrePage">
<td width="150" height="30"><div align="right"><a href="../product.do?method=showProductByTag&index=first&msg=${msg }">首页</a></div></td>
<td width="80" height="30"><div align="center"><a href="../product.do?method=showProductByTag&index=prew&pageno=${page.currentPage -1}&msg=${msg }">上一页</a></div></td>
</logic:equal>
<logic:notEqual value="true" name="page" property="hasPrePage">
<td width="150" height="30"><div align="right">首页</div></td>
<td width="80" height="30"><div align="center">上一页</div></td>
</logic:notEqual>
<logic:equal value="true" name="page" property="hasNextPage">
<td width="80" height="30"><div align="center"><a href="../product.do?method=showProductByTag&index=next&pageno=${page.currentPage +1 }&msg=${msg }">下一页</a></div></td>
<td width="80" height="30"><div align="center"><a href="../product.do?method=showProductByTag&index=end&pageno=${page.totalPage }&msg=${msg }">尾页</a></div></td>
</logic:equal>
<logic:notEqual value="true" name="page" property="hasNextPage">
<td width="80" height="30"><div align="center">下一页</div></td>
<td width="80" height="30"><div align="center">尾页</div></td>
</logic:notEqual>
<td height="30" colspan="3"><div align="center">页次${page.currentPage }/${page.totalPage } 共${page.totalCount }条记录</div> <div align="center"></div></td>
</tr>
可以显示相应的页面信息
然后productAction里面的showProductByTag代码如下：
Page page = new Page();
page.setEveryPage(10);
String pagemark = request.getParameter("goto");
if (pagemark == null) {
String state = request.getParameter("index");
String pageno = request.getParameter("pageno");
System.out.println("pageno=" + pageno);
if ("first".equals(state)) {
page.setCurrentPage(1);
Result result = pdp.productlist(page);
request.setAttribute("page", result.getPage());
request.setAttribute("productlist", result.getContent());
} else if ("prew".equals(state)) {
page.setCurrentPage(Integer.parseInt(pageno));
Result result = pdp.productlist(page);
request.setAttribute("page", result.getPage());
request.setAttribute("productlist", result.getContent());
} else if ("next".equals(state)) {
page.setCurrentPage(Integer.parseInt(pageno));
Result result = pdp.productlist(page);
request.setAttribute("page", result.getPage());
request.setAttribute("productlist", result.getContent());
} else if ("end".equals(state)) {
page.setCurrentPage(Integer.parseInt(pageno));
Result result = pdp.productlist(page);
request.setAttribute("page", result.getPage());
request.setAttribute("productlist", result.getContent());
}
} else {
page.setCurrentPage(Integer.parseInt(pagemark));
Result result = pdp.productlist(page);
request.setAttribute("page", result.getPage());
request.setAttribute("productlist", result.getContent());
}
return mapping.findForward("showProduct");