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 blocke.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 stubthis.doPost(request, response);}protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {// TODO Auto-generated method stubresponse.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 blocke.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;}}![[vscode]使用cmake时将命令行参数传递给调试目标](https://img-blog.csdnimg.cn/direct/1949876c1cb74d81b41dd1df671864d7.png)
