javaweb分页原理详解
本文实例为大家分享了javaweb分页原理的具体实现代码，供大家参考，具体内容如下
publicclassPage{
privateintcurrentPage;
privateinttotalPage;
privateintcount;
privateintPageSize;
privateListlist;
privateStringcategory;
}
servlet：
packagecom.learning.web.servlet;
importjava.io.IOException;
importjava.util.List;
importjavax.enterprise.inject.New;
importjavax.servlet.ServletException;
importjavax.servlet.annotation.WebServlet;
importjavax.servlet.http.HttpServlet;
importjavax.servlet.http.HttpServletRequest;
importjavax.servlet.http.HttpServletResponse;
importcom.learning.domain.Page;
importcom.learning.domain.Product;
importcom.learning.service.ProductService;
@WebServlet("/showProductByPage")
publicclassShowProductByPageextendsHttpServlet{
privatestaticfinallongserialVersionUID=1L;
protectedvoiddoGet(HttpServletRequestrequest,HttpServletResponseresponse)throwsServletException,IOException{
intcurrentPage=1;
intpageSize=4;
//第一次取为空
StringcurrentPageString=request.getParameter("currentPage");
if(currentPageString!=null){
currentPage=Integer.parseInt(currentPageString);
}
Stringcategory=request.getParameter("category");
if("".equals(category)){
category=null;
}
ProductServiceproductService=newProductService();
Pagepage=productService.showProductByPage(currentPage,pageSize,category);
request.setAttribute("page",page);
request.getRequestDispatcher("/product_list.jsp").forward(request,response);
}
protectedvoiddoPost(HttpServletRequestrequest,HttpServletResponseresponse)throwsServletException,IOException{
doGet(request,response);
}
}
service：
publicPageshowProductByPage(intcurrentPage,intpageSize,Stringcategory){
try{
Pagepage=newPage();
intcount=productDao.count(category);
page.setCount(count);
page.setList(productDao.findProductsByPage(currentPage,pageSize,category));
inttotalPage=(int)Math.ceil(1.0*count/pageSize);
page.setPageSize(pageSize);
page.setCurrentPage(currentPage);
page.setTotalPage(totalPage);
page.setCategory(category);
returnpage;
}catch(SQLExceptione){
e.printStackTrace();
}
returnnull;
}
Dao：
publicintcount(Stringcategory)throwsSQLException{
QueryRunnerqueryRunner=newQueryRunner(C3P0Util.getDataSource());
Stringsql="selectcount(*)fromproducts";
if(category!=null){
sql+="wherecategory='"+category+"'";
}
longl=(Long)queryRunner.query(sql,newScalarHandler(1));
return(int)l;
}
publicListfindProductsByPage(intcurrentPage,intpageSize,Stringcategory)throwsSQLException{
QueryRunnerqueryRunner=newQueryRunner(C3P0Util.getDataSource());
Stringsql="select*fromproducts";
if(category!=null){
sql+="wherecategory='"+category+"'";
}
sql+="limit?,?";
returnqueryRunner.query(sql,newBeanListHandler(Product.class),(currentPage-1)*pageSize,pageSize);
}
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毛票票。