SSH分页技术

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
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;
}


public int getBeginIndex() {
return beginIndex;
}


public void setBeginIndex(int beginIndex) {
this.beginIndex = beginIndex;
}


public int getCurrentPage() {
return currentPage;
}


public void setCurrentPage(int currentPage) {
this.currentPage = currentPage;
}


public int getEveryPage() {
return everyPage;
}


public void setEveryPage(int everyPage) {
this.everyPage = everyPage;
}


public boolean getHasNextPage() {
return hasNextPage;
}


public void setHasNextPage(boolean hasNextPage) {
this.hasNextPage = hasNextPage;
}


public boolean getHasPrePage() {
return hasPrePage;
}


public void setHasPrePage(boolean hasPrePage) {
this.hasPrePage = hasPrePage;
}


public int getTotalPage() {
return totalPage;
}


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

public static Page createPage(Page page, int totalRecords) {
return createPage(page.getEveryPage(), page.getCurrentPage(),
totalRecords);
}


//the basic page utils not including exception handler

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
public Result(Page page, List content) {
this.page = page;
this.content = content;
}


public List getContent() {
return content;
}


public Page getPage() {
return page;
}


public void setContent(List content) {
this.content = content;
}


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

//中间迭代所要显示的数据