Java中的分页实现

1,创建分页的实体类: 然后获得其属性的get和set方法   需要注意的是getTotalPage()方法需要修改下,计算出总页数

   public class UtilPage {

   public int totalPage;// 总页数

   public int rowsCount;// 总条数

   public int currentPage;// 当前页数

   public  final int pageSize = 3;// 页面显示条数

   public int getTotalPage() {

      if (rowsCount % pageSize == 0) {

         totalPage = (rowsCount / pageSize);

      } else {

         totalPage = (rowsCount / pageSize + 1);

      }

      return totalPage;

   }

  2,在Dao层中创建两个接口,然后再实现:  获取需要分页的数据(这个没啥难的)

        public List<Customer> getCustomer(int currentPage, int pageSize) {

      List<Customer> list = new ArrayList<>(0);

      ct = JDUtil.getConnection();

      String sql = "select * from t_customer c INNER JOIN t_dict d on c.custLevel=d.did limit ?,?";

      try {

         ps = ct.prepareStatement(sql);

         ps.setInt(1, (currentPage-1)*pageSize);

         ps.setInt(2, pageSize);

         rs = ps.executeQuery();

         while (rs.next()) {

        代码

         }

      } catch (Exception e) {

         e.printStackTrace();

      } finally {

         JDUtil.closeAll(ct, ps, rs);

      }

      return list;

   }

  //获取查询数据的总条数

   public int selectRowsCount() {

      int rowsCount=0;

      ct = JDUtil.getConnection();

      String sql = "select count(*) from t_customer";

      try {

         ps=ct.prepareStatement(sql);

         rs=ps.executeQuery();

         while(rs.next()){

            rowsCount=rs.getInt(1); 

         }

      } catch (Exception e) {

         e.printStackTrace();

      }finally {

         JDUtil.closeAll(ct, ps, rs);

      }

      return rowsCount;

   }

}

3,在service层中建立接口并实现:(我这是建立一个Map集合,一起存储需要分页的数据和数据总条数,也可以单独实现)

 public Map<String, Object> getLimitCustomer(int currentPage, int pageSize) {

      Map<String,Object> map=new HashMap<>();

      List<Customer> list = cd.getCustomer(currentPage, pageSize);

      int rowsCount = cd.selectRowsCount();

      map.put("list", list);

      map.put("rowsCount", rowsCount);

      return map;

   }

4,在control层中进行具体的Servlet处理

      UtilPage utilPage = new UtilPage();(这个是分页实体类对象)

      //获取当前页面

      int currentPage = Integer.parseInt(request.getParameter("currentPage"));

      Map<String, Object> limitCustomer = cs.getLimitCustomer(currentPage, utilPage.getPageSize());(利用对象调用service层的方法)

      //获取客户集合

      List<Customer> list =(List<Customer>)limitCustomer.get("list");

      int rowsCount =(int)limitCustomer.get("rowsCount");

      //将当前页面和总数据条数赋给对象

      utilPage.setRowsCount(rowsCount);

      utilPage.setCurrentPage(currentPage);

      request.setAttribute("utilPage", utilPage);

      request.setAttribute("list", list);

        //请求转发

        try {

         request.getRequestDispatcher("WEB-INF/customer/limitPage.jsp").forward(request, response);

      } catch (Exception e) {

         // TODO Auto-generated catch block

         e.printStackTrace();

      }

    5, 下边就是请求转发到所需要的jsp页面中的分页栏

    共[<font color="red"><B>${utilPage.rowsCount}</B></font>]条记录，共[<font color="red"><B>${utilPage.totalPage}</B></font>]页，当前第[<font color="red">              <B>${utilPage.currentPage}</B></font>]页

               <c:if test="${utilPage.currentPage!=1}">

               [<B><a href="Customer?C=getLimitCustomer&currentPage=1">首页</a></B>]

               [<B><a href="Customer?C=getLimitCustomer&currentPage=${utilPage.currentPage-1}">前一页</a></B>]

               </c:if>

               <c:if test="${utilPage.currentPage!=utilPage.totalPage}">

               [<B><a href="Customer?C=getLimitCustomer&currentPage=${utilPage.currentPage+1}">后一页</a></B>]

               [<B><a href="Customer?C=getLimitCustomer&currentPage=${utilPage.currentPage=utilPage.totalPage}">尾页</a></B>]

               </c:if>

这是主要的实现思想和代码,只要有web基础的都能看明白啥意思,不是完整的程序!!!