分页的自由点击和一整页的翻越

内容较多时,可以增加首位页进行选择:

java代码块:
package testPage;

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**

• Servlet implementation class TestPageServlet
  */
  @WebServlet("/TestPageServlet")
  public class TestPageServlet extends HttpServlet {
  private static final long serialVersionUID = 1L;

  /**

  • @see HttpServlet#HttpServlet()
    */
    public TestPageServlet() {
    super();
    // TODO Auto-generated constructor stub
    }

  /**

  • @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse

  •  response)
    

  */
  protected void doGet(HttpServletRequest request, HttpServletResponse response)
  throws ServletException, IOException {
  // TODO Auto-generated method stub
  List list = new ArrayList();
  int pageNo = 85;// 当前页码
  int totalPage = 90;// 总页码
  int start = 1;// 起始页码
  int end = 1;// 结束页码
  String pageNoParam = request.getParameter(“pageNo”);
  if (pageNoParam != null) {// 如果页码参数不为空,则覆盖默认页码1
  pageNo = Integer.parseInt(pageNoParam);
  }
  String isScroll = request.getParameter(“isScroll”);
  if (isScroll == null) {
  // 假设 显示窗口为 10个页码
  if (totalPage < 10) {// 当总页码 小于等于10的时候==>全部显示
  start = 1;
  end = totalPage;
  } else if (pageNo - 5 <= 1) {// 判断当处在 起始端边界时==>输出前10个页码
  start = 1;
  end = start + 9;
  } else if (pageNo + 4 >= totalPage) {// 判断当处于 结束端 边界时==>从后向前
  // 输出后10个页码
  end = totalPage;
  start = end - 9;
  } else {
  start = pageNo - 5;
  end = pageNo + 4;
  }
  for (int i = start; i <= end; i++) {
  list.add(i);
  }

   } else if (isScroll.equals("1")) {// 向后翻一轮
   	// 先算出 当前的 end值
   	// 接受 参数 end 和 start
   	String endStr = request.getParameter("end");
   	String startStr = request.getParameter("start");
  
   	if (endStr != null && !endStr.trim().equals("")) {
   		end = Integer.parseInt(endStr);
   	} // 将字符串类型转为int型
  
   	if (startStr != null && !startStr.trim().equals("")) {
   		start = Integer.parseInt(startStr);
   	}
   	if (end + 10 > totalPage) {// 如果结束码+10大于总页码==>处于最后一页
   		//System.out.println("22222222222"+end);
   		end = totalPage; // 结束码 就等于 总页数的页码
   		start = totalPage - 9; // 起始码与 结束码 相差 9
   	} else { // 相加不大于总页码 ==>不在最后一页==>可以进行一整页的 翻越
   		//System.out.println("1111111111111"+end);
   		start += 10;
   		end += 10;
   	}
   	pageNo = (start+end)/2+1;
   	
   	for (int i = start; i <= end; i++) {
   		list.add(i);
   	}
   } else {// 向前翻一轮
   	String endStr = request.getParameter("end");
   	String startStr = request.getParameter("start");
  
   	if (endStr != null && !endStr.trim().equals("")) {
   		end = Integer.parseInt(endStr);
   	} // 将字符串类型转为int型
  
   	if (startStr != null && !startStr.trim().equals("")) {
   		start = Integer.parseInt(startStr);
   	}
   	if (start - 10 <1) {//说明==>处于第一页
   		start = 1; 
   		end = start+9; 
   	} else { //不在第一页
   		start -= 10;
   		end -= 10;
   	}
   	pageNo = (start+end)/2+1;
   	for (int i = start; i <= end; i++) {
   		list.add(i);
   	}
   }
   request.setAttribute("pageList", list);
   request.setAttribute("curr_no", pageNo);
   request.setAttribute("totalPageNo", totalPage);
   request.setAttribute("start", start);
   request.setAttribute("end", end);
   request.getRequestDispatcher("Testpage.jsp").forward(request, response);
   ;
  

  }

  /**

  • @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse

  •  response)
    

  */
  protected void doPost(HttpServletRequest request, HttpServletResponse response)
  throws ServletException, IOException {
  // TODO Auto-generated method stub
  doGet(request, response);
  }

}

前端块(.jsp文件):
加 首 尾 的 jsp代码
<%@ page language=“java” contentType=“text/html; charset=UTF-8”
pageEncoding=“UTF-8”%>
<%@ taglib uri=“http://java.sun.com/jsp/jstl/core” prefix=“c”%>

• 		<c:if test="${start != 1}"><!-- 说明还没有到达最后的页码==>可以滚动 -->
  			<li><a href="TestPageServlet?pageNo=1"  <!-- 当起始码不等于1的时候,展示首页>
  				aria-label="Previous"> <span aria-hidden="true">首页</span>
  			</a></li>
  

• «

• 		<c:forEach items="${pageList}" var="no">
  			<!-- 当  集合中当前页码 等于页面中的当前页码时,使用一个空函数 使当前页码 不可再点击,使当前超链接失效   "#" 空锚链接,也会刷新页面 -->
  			<c:if test="${curr_no==no}">
  				<li class="active"><a href="javascript:void(0);">${no}</a></li>
  			</c:if>
  
  			<c:if test="${curr_no!= no}">
  				<li><a href="TestPageServlet?pageNo=${no}">${no}</a></li>
  			</c:if>
  		</c:forEach>
  		
  		<c:if test="${end != totalPageNo}"><!-- 说明还没有到达最后的页码==>可以滚动 -->
  			<li><a href="TestPageServlet?isScroll=1&start=${start}&end=${end}"
  				aria-label="Next"> <span aria-hidden="true">&raquo;</span>
  			</a></li>
  			<li><a href="TestPageServlet?pageNo=${totalPageNo}"
  				aria-label="Previous"> <span aria-hidden="true">尾页</span>
  			</a></li>
  		</c:if>
  	</ul>
  </nav>