1、对“jsp+servlet+javabean实现分页查询”功能做如下补充：
（1）记录批量删除：每个记录前添加复选框，点击批量删除，删除选中记录。
- 增加跳转到任意页功能。
- 用户可改变每页记录条数。
页面：
<%@ page pageEncoding="UTF-8" import="java.util.List,dao.StudentDao,entity.Student"%>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<!DOCTYPE html>
<html>
<head><title>模糊</title>
<script>
function qingchu(){
document.getElementById("sno").value='';
document.getElementById("sname").value='';
document.getElementById("sex").value='';
}
function jump1(pageNo){
var queryForm=document.getElementById("queryForm");
queryForm.pageNo.value=pageNo;
queryForm.submit();
}
function jump2(pageNo){
var pageNo1=document.getElementById("pageNo1").value;
if(pageNo1!=""){
jump1(pageNo1);
}
}
function btSelectAllOnclick(obj) {
var isCheck=obj.checked;
var inputs=document.getElementsByTagName("input");
for(var i=0;i<inputs.length;i++){
if(inputs[i].type=="checkbox" && inputs[i].id!="selectAll") //刷选出所有复选框
{
inputs[i].checked=obj.checked;
if(isCheck==true){
inputs[i].name="check";
}else{
inputs[i].name="user";
}
}
}
}
function getCheckBox()
{
var inputs=document.getElementsByTagName("input");
var chkInputs=new Array();
var j=0;
for(var i=0;i<inputs.length;i++)
{
if(inputs[i].type=="checkbox" && inputs[i].id!="selectAll") //刷选出所有复选框
{
chkInputs[j]=inputs[i];
j++;
}
}
return chkInputs;
}
function toChkSon(obj)
{
var isCheck=obj.checked;
obj.name="check";
if(isCheck==false) //单选复选框未选中 全选为未选
{
document.getElementById("selectAll").checked=false;
obj.name="user";
return ;
}
var chkInputs=getCheckBox();
var j=0;
for(var i=0;i<chkInputs.length;i++)
{
if(chkInputs[i].checked==isCheck)
j++;
else
break;
}
if(j==chkInputs.length) //当所有复选框为同一状态时 赋值全选同一状态
document.getElementById("selectAll").checked=isCheck;
}
function submitForm(){
document.getElementById("queryForm").submit();
}
function pagesizee(){
var pagesize=document.getElementById("pageSize").value;
if(pagesize!=""&&pagesize!=null){
document.getElementById("queryForm").submit();
}
}
</script>
<style>
th,td{
border:2px solid gray;
padding:3px;
text-align:center;
}
table,form{
border-collapse:collapse;
margin:0 auto;
text-align:center;
}
#pageSwitch{
margin:5px;
text-align:center;
}
</style>
</head>
<body>
<form method="post" action="${pageContext.request.contextPath}/student" id="queryForm">
学号<input type="text" name="sno" id="sno" value="${param.sno}">
姓名<input type="text" name="sname" id="sname" value="${param.sname}">
性别<input type="text" name="sex" id="sex" value="${param.sex}">
<input type="button" value="清除" onclick="qingchu()"/>
<input type="hidden" name="action" value="query3"/>
<input type="hidden" name="pageNo" value="1"/>
<input type="submit" value="查询"/>
<br>
<br>
<c:if test="${requestScope.recordCount==0}">
<div style="text-align:center">无记录</div>
</c:if>
<c:if test="${requestScope.recordCount>0}">
<table id="tab">
<tr>
<th><input type="checkbox" id="selectAll" name="selectAll" onclick="btSelectAllOnclick(this)"/></th>
<th>序号</th><th>学号</th><th>姓名</th><th>性别</th><th>修改</th><th>删除</th>
</tr>
<c:forEach items="${studentList}" var="student" varStatus="status">
<tr>
<td><input type="checkbox" onclick="toChkSon(this);" value="${student.id}" id="user" name="user"></td>
<td>${status.index+1}</td>
<td>${student.sno}</td>
<td>${student.sname}</td>
<td>${student.sex}</td>
<td><a href="${pageContext.request.contextPath}/student/edit.jsp?id=${student.id}&sno=${student.sno}&sname=${student.sname}&sex=${student.sex}">修改</a></td>
<td><a href="${pageContext.request.contextPath}/student?id=${student.id}&action=delete" onclick="return confirm('确实要删除该记录吗？')">删除</a></td>
</tr>
</c:forEach>
</table>
<input type="button" value="删除所选" onclick="submitForm()" />
<div id="pageSwitch">
共有记录${recordCount}条， 第${pageNo}/${pageCount}页，
<c:if test="${pageNo>1}">
<a href="javascript:jump1('1')">首页</a>
<a href="javascript:jump1('${pageNo-1}')">上页</a>
</c:if>
<c:if test="${pageNo==1}">
首页 上页
</c:if>
<c:if test="${pageNo<pageCount}">
<a href="javascript:jump1('${pageNo+1}')">下页</a>
<a href="javascript:jump1('${pageCount}')">末页</a>
</c:if>
<c:if test="${pageNo==pageCount}">
下页 末页
</c:if>
跳转到第<input type="text" name="pageNo1" id="pageNo1" value="" onclick="jump2('${pageNo}')">
页，每页<input type="text" name="pageSize" id="pageSize" value="" onclick="pagesizee()">
条
</div>
</c:if>
</form>
<%
String pagesize=request.getParameter("pageSize");
if(pagesize!=null&&pagesize!=""){
session.setAttribute("pageSize",pagesize);
}
%>
</body>
</html>Servlet：
private void query3(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
response.setContentType("text/html;charset=UTF-8");
request.setCharacterEncoding("UTF-8");
String users[]=request.getParameterValues("check");
StudentDao studentDao=new StudentDao();
HttpSession session=request.getSession();
if(users!=null){
for(int i=0;i<users.length;i++){//循环删除被选中的数据
try {
studentDao.delete(Integer.parseInt(users[i]));
} catch (Exception e) {
e.printStackTrace();
}
}
}
try {
String condition=" where 1=1 ";
String sno=request.getParameter("sno");
String sname=request.getParameter("sname");
String sex=request.getParameter("sex");
if(notEmpty(sno)) {
condition+=" and sno like '%"+sno+"%' ";
}
if(notEmpty(sname)) {
condition+=" and sname like '%"+sname+"%' ";
}
if(notEmpty(sex)) {
condition+=" and sex like '%"+sex+"%' ";
}
int pageNo=1;
int pageSize=10;
try {
pageNo=Integer.parseInt(request.getParameter("pageNo"));
} catch (Exception e) {
}
String pagesize=request.getParameter("pageSize");
String pagesize1=(String) session.getAttribute("pageSize");
if(pagesize!= null && !pagesize.equals("")) {
pageSize=Integer.parseInt(pagesize);
}else if(pagesize1!= null && !pagesize1.equals("")) {
pageSize=Integer.parseInt(pagesize1);
}
int recordCount=studentDao.getRecordCount(condition);
if(recordCount>0){
List<Student> studentList=studentDao.query(condition,"",pageNo,pageSize);
int t1=recordCount%pageSize;;
int t2=recordCount/pageSize;
int pageCount=(t1==0?t2:t2+1);
request.setAttribute("pageNo", pageNo);
request.setAttribute("pageCount", pageCount);
request.setAttribute("studentList", studentList);
}
request.setAttribute("recordCount", recordCount);
request.getRequestDispatcher("/student/query3.jsp").forward(request,response);
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}Dao：
public void delete(int id) throws Exception{
Connection conn = null;
PreparedStatement ps = null;
try {
conn = JdbcUtil.getConnection();
String sql = "delete from student where id=?";
ps = conn.prepareStatement(sql);
ps.setInt(1,id);
ps.executeUpdate();
}finally {JdbcUtil.free( null,ps, conn);}
}2、针对课程表数据库（数据库脚本下载）实现分页查询。同时按课程名、上课时间、上课地点、任课教师四列查询。
样例：http://47.93.11.179/test/courseServlet3
页面：
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8" import="java.util.List,dao.courseDao,entity.course"%>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<!DOCTYPE html>
<html>
<head>
<style>
body{
text-align:center;
}
th,td{
border:2px solid gray;
text-align:center;
padding:3px 10px;
}
table{
border-collapse:collapse;
margin:0 auto;
}
</style>
<script>
function jump1(pageNo){
document.getElementById("pageNo").value=pageNo;
document.getElementById("form11").submit();
}
function qc(){
document.getElementById("kcm").value="";
document.getElementById("sksj").value="";
document.getElementById("skdd").value="";
document.getElementById("rkjs1").value="";
}
</script>
<style>
.odd{
background-color:#E0EEEE;
}
</style>
</head>
<body>
<h2>课程表分页查询</h2>
<form action="${pageContext.request.contextPath}/courseServlet3" method="post" id="form11" >
课程名<input name="kcm" value="${param.kcm}" id="kcm">
上课时间<input name="sksj" value="${param.sksj}" id="sksj">
上课地点<input name="skdd" value="${param.skdd}" id="skdd">
任课教师<input name="rkjs1" value="${param.rkjs1}" id="rkjs1">
<input type="hidden" name="pageNo" id="pageNo" value="1"/>
<input type="submit" value="查询"/>
<input type="button" value="清除" onclick="qc()"/>
</form>
<br>
<c:if test="${requestScope.recordCount==0}">
<div style="text-align:center">无记录</div>
</c:if>
<c:if test="${requestScope.recordCount>0}">
<table>
<tr>
<th>学院</th><th>课序号</th><th>课程号</th><th>课程名</th><th>任课老师</th><th>上课时间</th><th>上课周次</th><th>上课地点</th><th>班级</th><th>年级</th><th>校区</th>
</tr>
<c:forEach items="${studentList}" var="student" varStatus="status">
<tr>
<td>${status.index+1}</td>
<td>${student.kxh}</td>
<td>${student.kch}</td>
<td>${student.kcm}</td>
<td>${student.rkjs1}</td>
<td>${student.sksj}</td>
<td>${student.skzc}</td>
<td>${student.skdd}</td>
<td>${student.bj}</td>
<td>${student.rs}</td>
<td>${student.xq}</td>
</tr>
</c:forEach>
</table>
<div id="pageSwitch">
共有记录${recordCount}条， 第${pageNo}/${pageCount}页，
<c:if test="${pageNo>1}">
<a href="javascript:jump1('1')">首页</a>
<a href="javascript:jump1('${pageNo-1}')">上页</a>
</c:if>
<c:if test="${pageNo==1}">
首页 上页
</c:if>
<c:if test="${pageNo<pageCount}">
<a href="javascript:jump1('${pageNo+1}')">下页</a>
<a href="javascript:jump1('${pageCount}')">末页</a>
</c:if>
<c:if test="${pageNo==pageCount}">
下页 末页
</c:if>
</div>
</c:if>
<br>
</body>
</html>
Servlet：
package servlet;
import java.io.IOException;
import java.io.PrintWriter;
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 dao.courseDao;
import entity.course;
@WebServlet("/courseServlet3")
public class CourseServlet extends HttpServlet{
private static final long serialVersionUID = 1L;
courseDao studentDao=new courseDao();
public CourseServlet() {
super();
// TODO Auto-generated constructor stub
}
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
this.doPost(request, response);
}
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
response.setContentType("text/html;charset=UTF-8");
request.setCharacterEncoding("UTF-8");
PrintWriter out = response.getWriter();
try {
String condition=" where 1=1 ";
String kcm=request.getParameter("kcm");
String sksj=request.getParameter("sksj");
String skdd=request.getParameter("skdd");
String rkjs1=request.getParameter("rkjs1");
if(notEmpty(kcm)) {
condition+=" and kcm like '%"+kcm+"%' ";
}
if(notEmpty(sksj)) {
condition+=" and sksj like '%"+sksj+"%' ";
}
if(notEmpty(skdd)) {
condition+=" and skdd like '%"+skdd+"%' ";
}
if(notEmpty(rkjs1)) {
condition+=" and rkjs1 like '%"+rkjs1+"%' ";
}
int pageNo=1;
int pageSize=10;
try {
pageNo=Integer.parseInt(request.getParameter("pageNo"));
} catch (Exception e) {
}
int recordCount=studentDao.getRecordCount(condition);
if(recordCount>0){
List<course> studentList=studentDao.query(condition,"",pageNo,pageSize);
int t1=recordCount%pageSize;
int t2=recordCount/pageSize;
int pageCount=(t1==0?t2:t2+1);
request.setAttribute("pageNo", pageNo);
request.setAttribute("pageCount", pageCount);
request.setAttribute("studentList", studentList);
}
request.setAttribute("recordCount", recordCount);
request.getRequestDispatcher("courseServlet.jsp").forward(request,response);
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
private boolean notEmpty(String s) {
return s!=null&&!"".equals(s.trim());
}
}Dao：
package dao;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.util.ArrayList;
import java.util.List;
import entity.course;
import util.JdbcUtil;
public class courseDao {
public List<course> query(String condition) throws Exception{
Connection conn = null;
PreparedStatement ps = null;
ResultSet rs = null;
List<course> studentList=new ArrayList<course>();
try {
conn = JdbcUtil.getConnection();
String sql = "select * from course "+condition;
ps=conn.prepareStatement(sql);
rs=ps.executeQuery();
while(rs.next()){
course student=new course();
student.setId(rs.getInt(1));
student.setXy(rs.getString(2));
student.setKxh(rs.getString(3));
student.setKch(rs.getString(4));
student.setKcm(rs.getString(5));
student.setRkjs1(rs.getString(9));
student.setSksj(rs.getString(11));
student.setSkzc(rs.getString(12));
student.setSkdd(rs.getString(13));
student.setBj(rs.getString(14));
student.setRs(rs.getString(16));
student.setXq(rs.getString(17));
studentList.add(student);
}
}finally {JdbcUtil.free(rs, ps, conn);}
return studentList;
}
public int getRecordCount(String condition) throws Exception{
Connection conn = null;
PreparedStatement pst = null;
ResultSet rs = null;
int recordcount=0;
try {
conn = JdbcUtil.getConnection();
String sql = "select count(*) from course "+condition;
pst = conn.prepareStatement(sql);
rs=pst.executeQuery();
rs.next();
recordcount=rs.getInt(1);
}finally {
JdbcUtil.free(rs, pst, conn);
}
return recordcount;
}
public List<course> query(String condition,String order,int pageNo,int pageSize) throws Exception{
Connection conn = null;
PreparedStatement ps = null;
ResultSet rs = null;
List<course> studentList=new ArrayList<course>();
try {
conn = JdbcUtil.getConnection();
String sql = "select * from course "+condition+order+" limit ?,?";
ps=conn.prepareStatement(sql);
ps.setInt(1, (pageNo-1)*pageSize);
ps.setInt(2, pageSize);
rs=ps.executeQuery();
while(rs.next()){
course student=new course();
student.setId(rs.getInt(1));
student.setXy(rs.getString(2));
student.setKxh(rs.getString(3));
student.setKch(rs.getString(4));
student.setKcm(rs.getString(5));
student.setRkjs1(rs.getString(9));
student.setSksj(rs.getString(11));
student.setSkzc(rs.getString(12));
student.setSkdd(rs.getString(13));
student.setBj(rs.getString(14));
student.setRs(rs.getString(16));
student.setXq(rs.getString(17));
studentList.add(student);
}
}finally {JdbcUtil.free(rs, ps, conn);}
return studentList;
}
}
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