JavaWeb学生成绩管理系统，编写了一个简单的学生成绩管理系统，完成学生信息及课程成绩的增删改查操作

资源内容介绍

我的文章：“【Java Web】学生成绩管理系统”的资源包，详细步骤可以参考文章。实验：JSP数据库程序设计实验目的：1.掌握JDBC的常用接口及类；2.掌握JDBC访问数据库的方法；实验内容及基本要求：实验内容：1.编写一个简单的学生成绩管理系统，完成学生信息及课程成绩的增删改查操作。基本要求：1．写出实验步骤2．写出实验中遇到的问题及解决的方法目录：Java Web实验_学生成绩管理系统2一、新建项目21.复制项目shop2二、结构21.框架结构22.代码结构3三、学生信息管理31.实体32.Dao层43.DaoImpl实现类44.Servlet控制器75.数据库76.Servlet 和 Student的jsp8四、课程成绩管理15(一)添加15(二)删除15(三)修改16(四)查询17实验问题171 复制的项目student直接部署然后访问，访问不到？17（1） 复制项目17（2） 问题18（3）修改上下文18（4）重新部署1

package student.util;import java.sql.Connection;import java.sql.DriverManager;import java.sql.PreparedStatement;import java.sql.ResultSet;import java.sql.SQLException;import java.sql.Statement;import java.util.ArrayList;import java.util.List;public class DBUtil {private static final String className = "com.mysql.jdbc.Driver";private static final String user = "root";private static final String password = "123456";private static final String url = "jdbc:mysql://localhost:3306/student";private static Connection connection;static{try {Class.forName(className);connection = DriverManager.getConnection(url, user, password);} catch (ClassNotFoundException e) {e.printStackTrace();} catch (SQLException e) {e.printStackTrace();}}public static Connection getConnection(){return connection;}public static ResultSet executeQuery(String sql){try {Statement st = connection.createStatement();return st.executeQuery(sql);} catch (SQLException e) {e.printStackTrace();return null;}}public static ResultSet executeQuery(String sql, Object[] params){try {PreparedStatement pst = connection.prepareStatement(sql);for(int i=0;i<params.length;i++){ if(params[i] instanceof Integer){ pst.setInt(i+1, (Integer)params[i]); }else if(params[i] instanceof String){ pst.setString(i+1, (String)params[i]); }else if(params[i] instanceof Float){ pst.setFloat(i+1, (Float)params[i]); }else if(params[i] instanceof Double){ pst.setDouble(i+1, (Double)params[i]); }else if(params[i] instanceof Boolean){ pst.setBoolean(i+1, (Boolean)params[i]); } }return pst.executeQuery();} catch (SQLException e) {e.printStackTrace();return null;}}public static int executeUpdate(String sql, Object[] params){try {PreparedStatement pst = connection.prepareStatement(sql);for(int i=0;i<params.length;i++){if(params[i] instanceof Integer){ pst.setInt(i+1, (Integer)params[i]);}else if(params[i] instanceof String){pst.setString(i+1, (String)params[i]);}else if(params[i] instanceof Float){pst.setFloat(i+1, (Float)params[i]);}else if(params[i] instanceof Double){pst.setDouble(i+1, (Double)params[i]);}else if(params[i] instanceof Boolean){pst.setBoolean(i+1, (Boolean)params[i]);} }return pst.executeUpdate();} catch (SQLException e) {e.printStackTrace();return 0;}}public static int executeUpdate(String sql){try {Statement st = connection.createStatement();return st.executeUpdate(sql);} catch (SQLException e) {e.printStackTrace();return 0;}}public static int getRecordCount(String tableName){ResultSet rs = executeQuery("select count(*) from " + tableName);try {rs.next();return rs.getInt(1);} catch (SQLException e) {e.printStackTrace();return 0;}}public static String page(String url,int pageNo,int totalPage, int num){Pagination pagination = new Pagination(pageNo, totalPage, num);List<String> pages = pagination.getPages();if(url.contains("?"))url += "&";if(!url.endsWith("&"))url += "?";StringBuffer pageStr = new StringBuffer();pageStr.append("<style>.page ul{list-style: none;}.page ul li{float: left;margin-right:5px;background-color: #ffffff;border: 1px solid #dddddd;border-radius: 6px;}.page .dot{padding:3px 8px;border: none;}.page ul li.current{border: 1px solid #ff5f00;background-color: #ff5f00;}.page ul li.current a{color: #ffffff;}.page ul li a{display: block;text-decoration: none;font-size:14px;padding: 6px 10px;color: #111111;}.page ul li a:hover{background-color: #ff5f00;color: #fff;border-radius: 6px;}.page select{outline: none;width:80px;height:30px;border:1px solid #dddddd;border-radius:6px;font-size: 14px;margin-right:5px;text-align: center;}.page input[type=\"text\"]{outline: none;width: 30px;height: 30px;font-size:14px;line-height: 30px;border-radius: 6px;text-align: center;margin-right:5px;border: 1px solid #dddddd;}.page input[type=\"text\"]:focus{border-color: #ff5f00;background-color: #FFFFFF;box-shadow: 0 0 0 2px rgba(255,95,0,0.2);}.page input[type=\"button\"]:hover{background-color:#f7f8fa;} .page input[type=\"button\"]{outline: none;width: 45px;height: 30px;line-height: 26px;border-radius: 6px;text-align: center;border: 1px solid #dddddd;background-color: #ffffff;cursor: pointer;font-color: 14px;}</style>");pageStr.append("<div class=\"page\">");pageStr.append("<ul>");if(pageNo == 1){pageStr.append("<li><a>&lt; 上一页</a></li>");}else{pageStr.append("<li><a href='" + url + "pageNo=" + (pageNo -1) + "'>&lt; 上一页</a></li>");}for(int i=0;i<pages.size();i++){if("...".equals(pages.get(i))){pageStr.append("<li class=\"dot\">...</li>");}else{if((pageNo+"").equals(pages.get(i))) pageStr.append("<li class=\"current\"><a>"+ pages.get(i) +"</a></li>");else pageStr.append("<li><a href='" + url + "pageNo=" + pages.get(i) + "'>"+ pages.get(i) +"</a></li>");}}if(pageNo == totalPage){pageStr.append("<li><a>下一页 &gt;</a></li>");}else{pageStr.append("<li><a href='" + url + "pageNo=" + (pageNo + 1) + "'>下一页 &gt;</a></li>");}pageStr.append("</ul>");pageStr.append("<script>");pageStr.append("function goPage(page){ ");pageStr.append("window.location='" + url + "pageNo=' + page;");pageStr.append("}");pageStr.append("function goPage1(){ ");pageStr.append("var page = document.getElementById('page').value;");pageStr.append("window.location='" + url + "pageNo=' + page;");pageStr.append("}");pageStr.append("</script>");pageStr.append("<select onchange='goPage(this.value)'>");for(int i=1;i<=totalPage;i++){if(i==pageNo) pageStr.append("<option selected value='" + i + "'>第" + i + "页</option>");else pageStr.append("<option value='" + i + "'>第" + i + "页</option>");}pageStr.append("</select>");pageStr.append("<input type='text' id='page'/>");pageStr.append("<input type='button' value='确定' onclick='goPage1();'/>");pageStr.append("</div>");pageStr.append("<script>");pageStr.append("document.getElementById('page').value='" + pageNo +"';");pageStr.append("</script>");return pageStr.toString();}}class Pagination {private int pageNo; //当前页号private int pageCount;//总页数private int floatCount;// 分页导航显示的页数public int getPageNo() {return pageNo;}public void setPageNo(int pageNo) {this.pageNo = pageNo;}public int getPageCount() {return pageCount;}public void setPageCount(int pageCount) {this.pageCount = pageCount;}public int getFloatCount() {return floatCount;}public void setFloatCount(int floatCount) {this.floatCount = floatCount;}public Pagination() {super();}public Pagination(int pageNo, int pageCount, int floatCount) {super();this.pageNo = pageNo;this.pageCount = pageCount;this.floatCount = floatCount;}public List<String> getPages(){List<String> pages = new ArrayList<String>();if(pageCount<=floatCount){for(int i=1;i<=pageCount;i++){pages.add(i + "");}}else if(pageNo<=floatCount/2){for(int i=1;i<=floatCount;i++){pages.add(i + "");}pages.add("...");pages.add(pageCount + "");}else if(pageNo>floatCount/2&&pageNo<pageCount-floatCount/2){pages.add("1");pages.add("...");for(int i=pageNo - floatCount/2 + 1;i<=pageNo + floatCount/2;i++){pages.add(i + "");}if(pageNo + floatCount/2 + 1!= pageCount) pages.add("...");pages.add(pageCount + "");}els