分页查询
作者:互联网
将所需数据建立一个实体类PageBean
需要获取当前页的值,并转为int类型
String currentPageStr=request.getParameter("currentPage"); Integer currentPage=Integer.parseInt(currentPageStr);
获取每页显示的条数,或手动设置
Integer currentCount=12; //Integer currentCount=request.getParameter("");
调用service层方法
PageBean<Product> page=productService.getPage(currentPage,currentCount);
Service:
PageBean<Product> page=new PageBean<Product>(); //目的:封装一个PageBean返回给客户端 //封装当前页 page.setCurrentPage(currentPage); //每页条数 page.setCurrentCount(currentCount); //封装总条数,count(*) int totalCount=0; try { totalCount=productDao.getTotalCount(); } catch (SQLException e) { e.printStackTrace(); } page.setTotalCount(totalCount); //总页数: 总条数/每页显示条数, *1.0向上取整 int totalPage=(int) Math.ceil(totalCount*1.0/currentCount); page.setTotalPage(totalPage); //每页显示的条数 // 起始页=(当前页-1)*每页显示条数 // 1,0,12 2,12,12 3,24,12 S=(n-1)*a //计算起始页的索引 int index=(currentPage-1)*currentCount; List<Product> list=null; //根据索引取值 try { list=productDao.getProductByPage(index, currentCount); } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } page.setList(list); return page; }
Dao层: select * from product limit ?,?
标签:currentCount,分页,int,查询,条数,PageBean,currentPage,page 来源: https://www.cnblogs.com/god3064371/p/11872036.html