jsp servlet javaBean后台分页实例代码解析

首先后台分页需要理清分页思路，把数据库里面需要分页的信息放到List集合中，然后按照页面反馈给后台的页码对List集合进行SubList切割把切完的List传到前端进行显示。

1.分页的demo文件结构图

导入的包

2.代码

SplitPageServlet代码

package ActionServlet;import java.io.IOException;import java.sql.SQLException;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;import Bean.ProjectBean;import Service.SplitPage;/** * Servlet implementation class SplitPageServlet */@WebServlet（"/SplitPageServlet"）public class SplitPageServlet extends HttpServlet { private static final long serialVersionUID = 1L; /*** @see HttpServlet#HttpServlet（）*/ public SplitPageServlet（） {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 stubList<ProjectBean>listArr = new ArrayList<ProjectBean>（）;String currrentPageString = request.getParameter（"currrentPage"）;String numberForSplitPage = request.getParameter（"numberForSplitPage"）;if（ currrentPageString ==null）{ currrentPageString = "1";}if（ numberForSplitPage == null）{ numberForSplitPage = "5";}SplitPage splitPage = new SplitPage（）;try { listArr = splitPage.AllSplitPage（numberForSplitPage, currrentPageString）; request.setAttribute（"subResult", listArr）;} catch （ClassNotFoundException | SQLException e） { // TODO Auto-generated catch block e.printStackTrace（）;}System.out.println（SplitPage.pageNumber）;System.out.println（SplitPage.currentPageIndex）;request.setAttribute（"pageNumber", SplitPage.pageNumber）;request.setAttribute（"currentPageIndex", SplitPage.currentPageIndex）;request.getRequestDispatcher（"/servlet/ShowViewIndex"）.forward（request, response）; } /*** @see HttpServlet#doPost（HttpServletRequest request, HttpServletResponse response）*/ protected void doPost（HttpServletRequest request, HttpServletResponse response） throws ServletException, IOException {// TODO Auto-generated method stubdoGet（request, response）; }}

ProjectBean代码

package Bean;public class ProjectBean { private String projectId = null; private String projectName = null; private String projectType = null; private String userNo = null; private String projectUser = null; public String getProjectId（）{if（projectId==null）{ projectId ="";}return this.projectId; } public void setProjectId（String projectId）{this.projectId = projectId; }public void setProjectName（String projectName）{this.projectName = projectName; }public String getProjectName（）{return this.projectName; }public void setType（String projectType）{this.projectType = projectType; }public String getProjectType（）{return this.projectType; }public void setUserNo（String userNo）{this.userNo = userNo; }public String getUserNo（）{return this.userNo; }public void setProjectUser（String projectUser）{this.projectUser = projectUser; }public String getProjectUser（）{return this.projectUser; } }

SplitPageBean 代码

package Bean;public class SplitPageBean { private int allitems;//总的记录数 private int currentRecord;//当前的记录数 private int lastPageRecord ; //上一页记录数开始数 private int nextPageRecord;//下一页记录数开始数 private int lastPageIndex ; //上一页 private int nextPageIndex;//下一页 private int currentPageIndex;//当前页 private int numberForSplitPage;//每页分的数量 private int allPageNumber; public int getAllitems（）{return this.allitems; } public void setAllitems（int allitems）{this.allitems = allitems;}public int getCurrentRecord（）{return this.currentRecord; } public void setCurrentRecord（int currentPageIndex）{this.currentRecord = currentPageIndex * this.numberForSplitPage;}public int getlastPageRecord（）{return this.lastPageRecord; } public void setLastPageRecord（int lastPageIndex）{this.lastPageRecord = lastPageIndex * this.numberForSplitPage;}public int getNextPageRecord（）{return this.nextPageRecord; } public void setNextPageRecord（int nextPageIndex）{this.nextPageRecord = nextPageIndex * this.numberForSplitPage;}public int getLastPageIndex（）{return this.lastPageIndex; } public void setLastPageIndex（int currentPageIndex）{this.lastPageIndex = currentPageIndex - 1;}public int getNextPageIndex（）{return this.nextPageIndex; } public void setNextPageIndex（int currentPageIndex）{this.nextPageIndex = currentPageIndex - 1;}public int getCurrentPageIndex（）{return this.currentPageIndex; } public void setCurrentPageIndex（int currentPageIndex）{this.currentPageIndex = currentPageIndex;}public int getNumberForSplitPage（）{return this.numberForSplitPage; } public void setNumberForSplitPage（int numberForSplitPage）{this.numberForSplitPage = numberForSplitPage;}public int getAllPageNumber（）{return this.allPageNumber; } public void setAllPageNumber（int allitems）{this.allPageNumber = allitems / this.numberForSplitPage + 1;}}

QueryProject代码

package Dao;import java.sql.Connection;import java.sql.ResultSet;import java.sql.SQLException;import java.sql.Statement;import java.util.ArrayList;import java.util.List;import Bean.ProjectBean;import Service.ConnectDataBase;public class QueryProject { private List<ProjectBean> listArr = new ArrayList（）; public List<ProjectBean> QueryAllProject（） throws ClassNotFoundException, SQLException{Connection conn=null;Statement stat=null;ResultSet rs=null;ConnectDataBase connectDataBase =new ConnectDataBase（）;conn = connectDataBase.connect（）;stat = conn.createStatement（）;rs = stat.executeQuery（"select*from project"）;while（rs.next（））{ ProjectBean projectBean = new ProjectBean（）; projectBean.setProjectId（rs.getString（"projectId"））; projectBean.setProjectName（rs.getString（"projectName"））; projectBean.setType（rs.getString（"projectType"））; projectBean.setUserNo（rs.getString（"UserNo"））; projectBean.setProjectUser（rs.getString（"projectUser"））; listArr.add（projectBean）;}connectDataBase.close（stat, conn）;return listArr; }// public static void main（String[] args） throws ClassNotFoundException, SQLException{//List<ProjectBean> listArr = new ArrayList（）;//QueryProject queryProject = new QueryProject（）;//listArr = queryProject.QueryAllProject（）;//ProjectBean projectBean = new ProjectBean（）;//projectBean = listArr.get（0）;//System.out.println（projectBean.getProjectId（））;//projectBean = listArr.get（2）;//System.out.println（projectBean.getProjectId（））;//System.out.println（listArr.size（））;// }}

ConenctDataBase代码

package Service;import java.sql.Connection;import java.sql.DriverManager;import java.sql.SQLException;import java.sql.Statement;public class ConnectDataBase { private String url = "jdbc:MySQL://localhost:3306/zhongchuangweb"; private String user = "root"; private String password = "12345";public Connection connect（） throws ClassNotFoundException, SQLException{ Class.forName（"com.mysql.jdbc.Driver"）; Connection conn = DriverManager.getConnection（url,user,password）;return conn; } //关闭数据库资源 public void close（Statement stat,Connection conn） throws SQLException{if（stat！=null）{stat.close（）;}if（conn！=null）{conn.close（）;} }}

SplitPage代码

package Service;import java.sql.SQLException;import java.util.ArrayList;import java.util.List;import Bean.ProjectBean;import Bean.SplitPageBean;import Dao.QueryProject;public class SplitPage { public static int pageNumber; public static int currentPageIndex; private List<ProjectBean> splitArr = new ArrayList（）;{QueryProject queryProject = new QueryProject（）;try { splitArr = queryProject.QueryAllProject（）;} catch （ClassNotFoundException | SQLException e） { // TODO Auto-generated catch block e.printStackTrace（）;} } public List<ProjectBean> AllSplitPage（String numberForSplitPage,String requestPageIndex） throws ClassNotFoundException, SQLException{List<ProjectBean> result = new ArrayList<ProjectBean>（）; int numberForSplitPageInt = Integer.parseInt（numberForSplitPage）;//每页的数量int requestPageIndexInt = Integer.parseInt（requestPageIndex）;//请求的页码SplitPageBean splitPageBean = new SplitPageBean（）;splitPageBean.setAllitems（splitArr.size（））;//设置总的记录数splitPageBean.setNumberForSplitPage（numberForSplitPageInt）;//设置每页的记录数量splitPageBean.setAllPageNumber（splitArr.size（））;pageNumber = splitPageBean.getAllPageNumber（）;splitPageBean.setCurrentPageIndex（requestPageIndexInt）;//设置请求页页码currentPageIndex = splitPageBean.getCurrentPageIndex（）;splitPageBean.setLastPageRecord（requestPageIndexInt-1）;if（splitPageBean.getAllitems（）<splitPageBean.getNumberForSplitPage（））{ result = splitArr;}else if（splitPageBean.getCurrentPageIndex（）*splitPageBean.getNumberForSplitPage（） > splitPageBean.getAllitems（））{ result = splitArr.subList（splitPageBean.getlastPageRecord（）,splitPageBean.getAllitems（））;}else{ result = splitArr.subList（splitPageBean.getlastPageRecord（）,splitPageBean.getlastPageRecord（）+splitPageBean.getNumberForSplitPage（））;//SubList用法不包含末尾索引}return result; } // public static void main（String[] args） throws ClassNotFoundException, SQLException{//List<ProjectBean> TestResult = new ArrayList<ProjectBean>（）; //ProjectBean projectBean = new ProjectBean（）;//SplitPage splitPage = new SplitPage（）;//TestResult = splitPage.AllSplitPage（"5","1"）;//projectBean = TestResult.get（0）;//System.out.println（projectBean.getProjectId（））;//projectBean = TestResult.get（1）;//System.out.println（projectBean.getProjectId（））;//projectBean = TestResult.get（2）;//System.out.println（projectBean.getProjectId（））;//projectBean = TestResult.get（3）;//System.out.println（projectBean.getProjectId（））;//projectBean = TestResult.get（4）;//System.out.println（projectBean.getProjectId（））;//projectBean = TestResult.get（5）;//System.out.println（projectBean.getProjectId（））;//// }}

显示层
ShowViewIndex代码

package View;import java.io.IOException;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 ShowViewIndex */@WebServlet（"/ShowViewIndex"）public class ShowViewIndex extends HttpServlet { private static final long serialVersionUID = 1L; /*** @see HttpServlet#HttpServlet（）*/ public ShowViewIndex（） {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 stubrequest.getRequestDispatcher（"/NewFile.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 stubdoGet（request, response）; }}

jsp页面代码

<%@ page language="java" contentType="text/html; charset=utf-8" pageEncoding="utf-8"%><%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%><！DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"><html><head><meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"><title>数据库内容分页显示</title><style type="text/css">*{ margin:0; padding:0;}ul li{ width:50px; height:24px; line-height:24px; float:left; margin-left:0px; display:inline; margin-top:5px; overflow:hidden;}ul li button{width:50px;height:24px;margin:0px;padding:0px;}</style></head><body> <table><thead> <tr><th style="text-align:center;">编号</th><th style="text-align:center;">名称</th><th style="text-align:center;">类型</th><th style="text-align:center;">学号</th><th style="text-align:center;">负责人</th> </tr></thead><tbody><c:forEach var="project" items="${subResult}"> <tr><td><c:out value="${project.projectId}"></c:out></td><td><c:out value="${project.projectName}"></c:out></td><td><c:out value="${project.projectType}"></c:out></td><td><c:out value="${project.userNo}"></c:out></td><td><c:out value="${project.projectUser}"></c:out></td> </tr></c:forEach></tbody> </table> <div align = "center"><ul><c:choose> <c:when test="${currentPageIndex>1}"> <li><a href="${pageContext.request.contextPath}/servlet/SplitPageServlet?currrentPage=${currentPageIndex-1}"><button><</button></a></li> </c:when> <c:otherwise> <li><a><button><</button></a></li> </c:otherwise></c:choose> <%int i =（Integer）request.getAttribute（"pageNumber"）; for （int j=0;j<i;j++） {%> <li><a href="${pageContext.request.contextPath}/servlet/SplitPageServlet?currrentPage=<%=j+1%>"><button><%=j+1%></button></a></li><%}%> <c:choose> <c:when test="${currentPageIndex+1<=pageNumber}"> <li><a href="${pageContext.request.contextPath}/servlet/SplitPageServlet?currrentPage=${currentPageIndex+1}"><button>></button></a></li> </c:when> <c:otherwise> <li><a><button>></button></a></li> </c:otherwise></c:choose></ul></div> </body></html>

xml代码

<?xml version="1.0" encoding="UTF-8"?><web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" version="2.5"> <display-name></display-name> <welcome-file-list> <welcome-file>SplitPageServlet</welcome-file> </welcome-file-list><servlet> <servlet-name>ShowViewIndex</servlet-name> <servlet-class>View.ShowViewIndex</servlet-class> </servlet> <servlet-mapping> <servlet-name>ShowViewIndex</servlet-name> <url-pattern>/servlet/ShowViewIndex</url-pattern> </servlet-mapping> <servlet> <servlet-name>SplitPageServlet</servlet-name> <servlet-class>ActionServlet.SplitPageServlet</servlet-class> </servlet> <servlet-mapping> <servlet-name>SplitPageServlet</servlet-name> <url-pattern>/servlet/SplitPageServlet</url-pattern> </servlet-mapping></web-app>

运行结果展示

数据库describe

同时在本次demo中认识到了xml的中使用欢迎界面通过 <welcome-file-list> <welcome-file>静态界面（jsp html）</welcome-file> </welcome-file-list>还可以使用servlet直接用servlet名即可。
初学java和javaee 写一点自己做的东西，代码写的不是很规范，不喜勿喷。
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脚本之家。