JAVA连接数据库实验
1.实验思路
本实验后端采用的是JDBC连接数据库，服务端和客户端的连接采用的是servlet开发工具，主要的结构是采用servlet作为中间层实现信息交互和页面的重定向，后端则是采用JDBC实现页面和MYSQL数据库的交互。
2.代码结构图
3.实验开发工具
Intelij -IU 2018.3.6 旗舰版（ 因为后续要使用tomcat插件，社区版没有该功能）
附上链接https://www.cnblogs.com/xin1006/p/11414278.html
Tomcat服务器的部署（用来实现servlet工具）
数据库MYSQL 8.0 外加连接工具 NAVICAT
对应数据库版本的JDBC驱动程序的 mysql-connector-java连接包
4.实验正式准备
（1）数据库 MYSQL（安装和连接首先自己实现）（免安装版也可以，那样其实可以直接用命令行）
数据库
内部包含两张表 
login表 
student表 
（2）IDEA环境部署
1.首先获得对应的驱动包，这里我附上对应的链接
链接 提取码：a527
2.安装Tomcat（首先记得先安装JDK,不做相关的赘述 )
附上参考 https://www.jb51.net/article/137404.htm
安装之后打开 localhost:8080（检查是否出现Tomcat，如果没有出现就是安装失败，可能是接口冲突，或者是相关的环境路径有误）
3.IDEA配置
new一个新的project
勾选web 选择对应的jdk（我这里版本稍微高了点)
最后取上名字 （路径不能有中文，安装Tomcat的路径也不能有中文，路径不宜过长）
最终得到如下图
手动打开此路径
WEB-INF目录下新建子目录，叫做lib里面存放我们相关要用到的包，把刚刚我们的connect.jar的驱动包放入
继续进入IDEA进行操作 ，打开刚刚jar包放入的文件夹lib，右键jar包，选择ADD as Library，点击ok，点击右上角确认是否配置完成
接下来是配置Tomcat（这个才是本文的关键）
点击上图的Add Configuration
server无需改动
这个就是配置输出路径 修改一下，确认
运行，然后看弹出界面，成功弹出下图ok
生成的.class文件会存放到out目录之中
5.实验正式代码部署
src目录下新建三级文件目录，com目录 ，子目录zsh目录
及其zsh目录下所属的三个子目录，分别是util，servlet，bean目录
重定向框图（时间上比较赶，可能有些地方漏掉了）
代码
Student 数据信息表（实现信息的接口）
package com.zsh.bean;
/// 信息表层
import java.util.ArrayList;
import java.util.List;
public class Student {
private int id;/// 编号
private String name;/// 姓名
private int age;/// 年龄
private String sex;/// 性别
private int grade;/// 成绩
private String address;/// 地址
public int get_id()
{
return id;
}
public void set_id(int ID)
{
this.id = ID;
}
public String get_name()
{
return name;
}
public void set_name(String name)
{
this.name = name;
}
public int get_age()
{
return age;
}
public void set_age(int age)
{
this.age =age;
}
public String get_sex()
{
return sex;
}
public void set_sex(String sex)
{
this.sex = sex;
}
public int get_grade()
{
return grade;
}
public void set_grade(int grade)
{
this.grade = grade;
}
public String get_address()
{
return address;
}
public void set_address(String address)
{
this.address = address;
}
}
数据库连接，DBcon类 其他的基本大家都应该知晓 ，我就简单说一下我踩的坑 final String DRIVER_NAME = "com.mysql.cj.jdbc.Driver";
//数据库连接地址
final String URL = "jdbc:mysql://localhost:3306/school?serverTimezone=UTC&useSSL=false";
//用户名,更换成你自己的用户名，此处为root用户
final String USER_NAME = "root";
//密码，更换成你自己设定的密码
final String PASSWORD = "root";
school是我的数据库名字，到时候改成自己的就可以了
貌似是MYSQL 5.0以下和5.0以上的驱动代码不同
8.0的final String DRIVER_NAME = "com.mysql.cj.jdbc.Driver";
5.0以下的final String DRIVER_NAME = "com.mysql.jdbc.Driver";
还有就是这个，？后面表示带的参数，一个主要是用来调整时区，核对MYSQL的时区，另外一个https://www.cnblogs.com/MonkeySun/p/13406050.html
final String URL = "jdbc:mysql://localhost:3306/school?serverTimezone=UTC&useSSL=false";
package com.zsh.util;
import com.mysql.cj.jdbc.exceptions.NotUpdatable;
import com.mysql.cj.xdevapi.SqlDataResult;
import java.sql.*;
public class DBcon {
public static Connection getconn()
{
final String DRIVER_NAME = "com.mysql.cj.jdbc.Driver";
//数据库连接地址
final String URL = "jdbc:mysql://localhost:3306/school?serverTimezone=UTC&useSSL=false";
//用户名,更换成你自己的用户名，此处为root用户
final String USER_NAME = "root";
//密码，更换成你自己设定的密码
final String PASSWORD = "root";
Connection connection = null;/// 驱动对象
try {
//加载mysql的驱动类
Class.forName(DRIVER_NAME);
connection = DriverManager.getConnection(URL, USER_NAME, PASSWORD);
}catch (SQLException e)
{
e.printStackTrace();
}catch(ClassNotFoundException e)
{
e.getException();
}
return connection;
}
public static void closeconn(Connection con, PreparedStatement pre, ResultSet rs)
{
if (con!=null)
{
try{
con.close();
}catch(SQLException e)
{
e.printStackTrace();
}
}
if (pre!=null)
{
try{
pre.close();
}catch(SQLException e){
e.printStackTrace();
}
}
if (rs!=null)
{
try{
rs.close();
}catch (SQLException e)
{
e.printStackTrace();
}
}
}
}
loginservlet (是用来实现登陆操作）
说明：doPost()函数是固定格式
继承HttpServlet接口需要实现doPost方法或者doGet方法
这两个方法的区别是doPost 是密文通道（也就是隐藏了）
doGet方法则会将你之前所在页面输入的所有信息放到重定向的URL里面（也就是明文） 所以虽然并不是什么严谨的项目，url后缀太长也很难匹配
还是先简单说明一下
HttpServletRequest request,HttpServletResponse response///这两个参数 request获取当前页面所输入的信息
/// response是返回信息到页面的接口
///默认的response和request采用的是ios--8859-1编码 最终需要转化为utf-8
request.setCharacterEncoding("utf-8");
response.setCharacterEncoding("utf-8");
response.setHeader("Content-Type","text/html;charset=utf-8");
/// getParameter可以理解为按照指定参数获得对应页面的数据
/// 比如说下图两个文本框，name和id都是我们所需要的参数
/// 那么我在和他连接的servlet之中就能调用该函数获取对应的id的信息
String name = request.getParameter("name");
String pwd = request.getParameter("pwd");
package com.zsh.servlet;
import com.zsh.util.DBcon;
import javax.print.DocFlavor;
import javax.servlet.http.HttpServlet;
import java.util.concurrent.TimeUnit;
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 java.io.IOException;
import java.io.PrintWriter;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
@WebServlet("/login")/// 声明 servlet框架需要你写上存在哪些servlet，新版本的就可以按照此种声明方式
///说明下一次重定向之后的URL路径就是https://...../login
public class loginservlet extends HttpServlet {/// 继承该接口是因为其他接口需要重写一些方法
protected void doPost(HttpServletRequest request,HttpServletResponse response)throws ServletException, IOException
{
request.setCharacterEncoding("utf-8");
response.setCharacterEncoding("utf-8");
response.setHeader("Content-Type","text/html;charset=utf-8");
String name = request.getParameter("name");
String pwd = request.getParameter("pwd");
boolean flag = false;
Connection con = DBcon.getconn();///连接数据库
PreparedStatement ps = null;
ResultSet rs = null;
String sql = "select * from login where name = ? and pwd = ?";
PrintWriter out = response.getWriter();
try {
ps = con .prepareStatement(sql);
ps.setString(1,name);
ps.setString(2,pwd);
rs = ps.executeQuery();/// 获取查询结果
if(rs.next()){/// 如果存在next就说明查询到了该账号，所以就登录成功
flag = true;
}else{
flag = false;
}
} catch (SQLException e) {
e.printStackTrace();
}finally {
DBcon.closeconn(con,ps,rs);
}
if(flag){
response.sendRedirect("jdbc.jsp");/// 页面重定向 跳转到添加数据的页面
out.println("登录成功");
}else {
response.sendRedirect("error.jsp");
}
}
}
index.jsp连接的是loginservlet
<%--
Created by IntelliJ IDEA.
User: cdk13
Date: 2021/6/7
Time: 15:14
To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>登录</title>
</head>
<body>
<form action="/login" method="post">
<--%上面说明的是action连接对象，method就是处理的方法，如果写上get就是对应doGet方法，否则就是doPost方法%-->
<table align="center" border="1 " width="50%" cellpadding="6">
<tr>
<td align="center" >账号：</td>
<td align="left" ><input type="text" name="name" id="name"></td>
</tr>
<tr>
<td align="center" >密码：</td>
<td align="left" ><input type="text" name="pwd" id="pwd"></td>
</tr>
<tr>
<th colspan="2" align="center" ><a href="register.jsp" >注册请点击此处 </a> <input type="submit" name="submit" value="登录" ></th>
<--%弄一个超链接%-->
</tr>
</table>
</form>
</body>
</html>
registerservlet.java
package com.zsh.servlet;
import com.zsh.util.DBcon;
import javax.print.DocFlavor;
import javax.servlet.http.HttpServlet;
import java.util.ArrayList;
import java.util.concurrent.TimeUnit;
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 java.io.IOException;
import java.io.PrintWriter;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.*;
@WebServlet("/register")
public class registerservlet extends HttpServlet{
protected void doPost(HttpServletRequest request,HttpServletResponse response)throws ServletException, IOException {
request.setCharacterEncoding("utf-8");
response.setCharacterEncoding("utf-8");
response.setHeader("Content-Type", "text/html;charset=utf-8");
String name = request.getParameter("name");
String pwd1 = request.getParameter("pwd1");
String pwd2 = request.getParameter("pwd2");
String sql = "insert into login(name,pwd) values(?,?)";
Connection conn = DBcon.getconn();
PreparedStatement ps = null;
ResultSet rs = null;
boolean flag = false;
List<String >error = new ArrayList<>();///该参数主要是用来传递报错，主要传送给error1.jsp
if (name.equals("")||pwd1.equals("")||pwd2.equals(""))///一个为空，添加报错参数
{
if (name.equals(""))error.add("请输入用户名
");
if (pwd1.equals(""))error.add("请输入密码
");
if (pwd2.equals(""))error.add("请确认密码
");
if (!error.isEmpty()) {
request.setAttribute("error", error);
request.getRequestDispatcher("error1.jsp").forward(request, response);///这两句就是传递参数从servlet到jsp的关键
}
response.sendRedirect("error1.jsp");/// 重定向
}
if (pwd1==pwd2) {
try {
ps = conn.prepareStatement(sql);
ps.setString(1, name);
ps.setString(2, pwd1);
rs = ps.executeQuery();
if(rs.next()){
flag = true;
}else{
flag = false;
}
if (flag)
{
response.sendRedirect("error1.jsp");
}
else ps.executeUpdate();
} catch (SQLException e) {
e.printStackTrace();
} finally {
DBcon.closeconn(conn, ps, null);
}
response.sendRedirect("success.jsp");
}
else {
error.add("两次输入密码不一致
");
if (!error.isEmpty()) {
request.setAttribute("error", error);
request.getRequestDispatcher("error1.jsp").forward(request, response);
}
response.sendRedirect("error1.jsp");
}
}
}
selectservlet
这里有一个特别值得注意的地方 因为我们要显示所有的学生信息
all.jsp之中显示，但是一般是从all.jsp之中获得参数之后传回selectservlet ，所以为了显示信息首先我们要先定向到selectservlet 获得信息之后再重定向到all.jsp
package com.zsh.servlet;
import com.mysql.cj.xdevapi.DbDoc;
import com.mysql.cj.xdevapi.SqlDataResult;
import com.zsh.bean.Student;
import com.zsh.util.DBcon;
import javax.print.DocFlavor;
import javax.servlet.http.HttpServlet;
import java.sql.*;
import java.util.ArrayList;
import java.util.concurrent.TimeUnit;
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 java.io.IOException;
import java.io.PrintWriter;
import java.sql.Statement;
import java.util.*;
@WebServlet("/select")
public class selectservlet extends HttpServlet{
protected void doPost(HttpServletRequest request,HttpServletResponse response)throws ServletException, IOException {
request.setCharacterEncoding("utf-8");
response.setCharacterEncoding("utf-8");
response.setHeader("Content-Type", "text/html;charset=utf-8");
String sql = "select * from student ";
Connection conn = DBcon.getconn();
try {
PreparedStatement ps = null;
ps = conn.prepareStatement(sql);
ResultSet rs = ps.executeQuery();
List <Student> list = new ArrayList<Student>();/// 这里由于我们要在当前页面显示所有 的学生信息，所以就需要存下来，传递个和他当前相关联的all.jsp
while (rs.next())
{
Student stu =new Student();
stu.set_id(rs.getInt("id"));
stu.set_name(rs.getString("name"));
stu.set_sex(rs.getString("sex"));
stu.set_age(rs.getInt("age"));
stu.set_grade(rs.getInt("grade"));
stu.set_address(rs.getString("address"));
list.add(stu);
}
request.setAttribute("list", list);///和上面一样的，传递给jsp
DBcon.closeconn(conn,ps,rs);
}catch (SQLException e)
{
e.printStackTrace();
}
request.getRequestDispatcher("all.jsp").forward(request, response);
}
public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException
{
doPost(request, response);
}
public void destroy()
{
super.destroy();
}
}
all.jsp
Listlist = (List )request.getAttribute("list");
上面这句话就是从selectservlet获取对应的学生信息，然后实现显示
删除
修改
上面是两个超链接,一个是链接deleteservlet ，另一个是update.jsp
为什么不需要delete.jsp呢因为我当前获得对应的id我就知道我要删除的对象
删除他的所有参数即可、
但是更新就需要一个界面来针对指定的页面更新
<%--
Created by IntelliJ IDEA.
User: cdk13
Date: 2021/6/8
Time: 13:01
To change this template use File | Settings | File Templates.
--%>
<%@page import="java.util.ArrayList"%>
<%@page import="java.util.List"%>
<%@page import="com.zsh.bean.Student"%>
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<body>
<table id="table1" align="center" border="1" width="50%" cellpadding="6">
<tr>
<th colspan="6" align="center" >查询到的学生信息</th><%--th加粗， cellpadding和android padding含义一样--%>
</tr>
<tr>
<th align="center" >ID</th>
<th align="center" >学生姓名</th>
<th align="center" >年龄</th>
<th align="center" >性别</th>
<th align="center" >成绩</th>
<th align="center" >地址</th>
<th align="center" >操 作</th>
</tr>
<%
//获取图书信息集合
List<Student> list = (List<Student>)request.getAttribute("list");
if(list == null || list.size() < 1){
out.print("没有数据 ");
}else{
for(Student s:list){
%>
<tr align="center">
<td> <%= s.get_id() %></td>
<td> <%= s.get_name()%></td>
<td> <%= s.get_age() %></td>
<td> <%= s.get_sex()%></td>
<td> <%= s.get_grade()%></td>
<td> <%= s.get_address()%></td>
<td>
<a href="delete?id=<%=s.get_id() %>">删除</a>
<a href="update.jsp?id=<%=s.get_id() %>">修改</a>
</td>
</tr>
<%
}
}
%>
</table>
</body>
</html>
updateservlet
提醒一下@WebServlet("/update") 一定要加上/
package com.zsh.servlet;
import com.zsh.util.DBcon;
import javax.print.DocFlavor;
import javax.servlet.http.HttpServlet;
import java.util.ArrayList;
import java.util.concurrent.TimeUnit;
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 java.io.IOException;
import java.io.PrintWriter;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.*;
@WebServlet("/update")
public class updateservlet extends HttpServlet{
protected void doPost(HttpServletRequest request,HttpServletResponse response)throws ServletException, IOException {
request.setCharacterEncoding("utf-8");
response.setCharacterEncoding("utf-8");
response.setHeader("Content-Type", "text/html;charset=utf-8");
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
String id = request.getParameter("id");
String name = request.getParameter("name");
String age = request.getParameter("age");
String sex = request.getParameter("sex");
String grade = request.getParameter("grade");
String address = request.getParameter("address");
String sql = "update student set name =?,age = ?,sex = ?,grade = ?,address=? where id= ?";
Connection conn = DBcon.getconn();
PreparedStatement ps = null;
ResultSet rs = null;
boolean flag = false;
if (name == null||age== null ||sex == null ||grade==null ||address == null)
{
PrintWriter out = response.getWriter();//// 传递信息回对应界面的接口
out.print("更新失败!");
response.setHeader("Refresh", "1;jdbc.jsp");
}
try
{
conn = DBcon.getconn();
ps = conn.prepareStatement(sql);
ps.setString(1, name);
ps.setInt(2, Integer.parseInt(age));
ps.setString(3,sex);
ps.setInt(4, Integer.parseInt(grade));
ps.setString(5, address);
ps.setInt(6, Integer.parseInt(id));
int row = ps.executeUpdate();
PrintWriter out = response.getWriter();
/// List<String > error = new LinkedList<String >();
if(row > 0){
out.print("更新成功!");
response.setHeader("Refresh", "1;jdbc.jsp");
}
else {
out.print("更新失败!");
response.setHeader("Refresh", "1;jdbc.jsp");
}
}catch (SQLException e)
{
e.printStackTrace();
}
finally {
DBcon.closeconn(conn,ps,rs);
}
}
protected void doGet(HttpServletRequest request,HttpServletResponse response)throws ServletException, IOException {
doPost(request,response);
}
}
deleteservlet
这里主要是一点，删除最后要更新页面，所以又要定向到selectservlet，重新显示all.jsp，对应的id是之前的all.jsp之中删除 ?后面附加的id参数
package com.zsh.servlet;
import com.zsh.util.DBcon;
import javax.print.DocFlavor;
import javax.servlet.http.HttpServlet;
import java.util.ArrayList;
import java.util.concurrent.TimeUnit;
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 java.io.IOException;
import java.io.PrintWriter;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.*;
@WebServlet("/delete")
public class deleteservlet extends HttpServlet{
protected void doPost(HttpServletRequest request,HttpServletResponse response)throws ServletException, IOException {
request.setCharacterEncoding("utf-8");
response.setCharacterEncoding("utf-8");
response.setHeader("Content-Type", "text/html;charset=utf-8");
String sql = "delete from student where id = ?";
Connection conn = DBcon.getconn();
String id = request.getParameter("id");
PreparedStatement ps = null;
try {
ps = conn.prepareStatement(sql);
ps.setInt(1,Integer.parseInt(id));
ps.executeUpdate();
}catch(SQLException e)
{
e.printStackTrace();
}finally {
DBcon.closeconn(conn,ps,null);
}
response.sendRedirect("/select");/// 重定向 删除之后到达
}
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
doPost(request,response);
}
}
insertservlet
package com.zsh.servlet;
import com.mysql.cj.xdevapi.DbDoc;
import com.zsh.util.DBcon;
import javax.print.DocFlavor;
import javax.servlet.http.HttpServlet;
import java.util.ArrayList;
import java.util.concurrent.TimeUnit;
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 java.io.IOException;
import java.io.PrintWriter;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.*;
@WebServlet("/insert")
public class insertservlet extends HttpServlet{
protected void doPost(HttpServletRequest request,HttpServletResponse response)throws ServletException, IOException {
request.setCharacterEncoding("utf-8");
response.setCharacterEncoding("utf-8");
response.setHeader("Content-Type", "text/html;charset=utf-8");
String id = request.getParameter("id");
String name = request.getParameter("name");
String age = request.getParameter("age");
String sex = request.getParameter("sex");
String grade = request.getParameter("grade");
String address = request.getParameter("address");
Connection conn = null;
String sql = "insert into student(id,name,age,sex,grade,address) values(?,?,?,?,?,?)";
try{
conn = DBcon.getconn();
PreparedStatement ps = conn.prepareStatement(sql);
ps.setInt(1, Integer.parseInt(id));
ps.setString(2, name);
ps.setInt(3, Integer.parseInt(age));
ps.setString(4,sex);
ps.setInt(5, Integer.parseInt(grade));
ps.setString(6, address);
int row = ps.executeUpdate();
PrintWriter out = response.getWriter();
if(row > 0){
out.print("成功添加了 " + row + "条数据！ ");
response.setHeader("Refresh", "1;jdbc.jsp");
}
if(ps!=null){
try {
ps.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
if(conn!=null){
try {
conn.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}catch(Exception e) {
PrintWriter out = response.getWriter();
out.print("图书信息添加失败 请重新输入" + e.toString());
response.setHeader("Refresh", "1;jdbc.jsp");/// 停留一秒在转到对应页面
}
}
}
error.jsp
<%@ page import="java.util.concurrent.TimeUnit" %>
<%@ page import="java.io.PrintWriter" %><%--
Created by IntelliJ IDEA.
User: cdk13
Date: 2021/6/7
Time: 20:53
To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>输入错误</title>
登录失败，请重新输入!<br/>
</head>
<body>
<%response.setHeader("Refresh", "1;index.jsp"); %>
</body>
</html>
error1.jsp 用来处理基本的异常信息
<%--
Created by IntelliJ IDEA.
User: cdk13
Date: 2021/6/7
Time: 23:12
To change this template use File | Settings | File Templates.
--%>
<%@page import="java.util.ArrayList"%>
<%@page import="java.util.List"%>
<%@page import="java.lang.String"%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<jsp:useBean id="x" class="com.zsh.servlet.registerservlet"></jsp:useBean>
<jsp:setProperty property="*" name="x"/>
<html>
<head>
<title>注册失败</title>
<%
List<String> errors = (List<String>) request.getAttribute("error");
for (String error : errors) {
out.println("<li>" + error + "</li>");
}
%>
</head>
<body>
<%response.setHeader("Refresh", "1;index.jsp"); %>
</body>
</html>
jdbc.jsp 添加学生信息
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<body>
<form action="/insert" method="post">
<table align="center" border="1 " width="50%" cellpadding="6">
<tr>
<th colspan="2" align="center" >添加学生信息</th><%--th加粗， cellpadding和android padding含义一样--%>
</tr>
<tr>
<td align="center" >学生ID：</td>
<td align="left" ><input type="text" name="id"></td>
</tr>
<tr>
<td align="center" >学生名字：</td>
<td align="left" ><input type="text" name="name"></td>
</tr>
<tr>
<td align="center" >年 龄：</td>
<td align="left" ><input type="text" name="age"></td>
</tr>
<tr>
<td align="center" >性 别：</td>
<td align="left" ><input type="text" name="sex"></td>
</tr>
<tr>
<td align="center" >成 绩：</td>
<td align="left" ><input type="text" name="grade"></td>
</tr>
<tr>
<td align="center" >地 址：</td>
<td align="left" ><input type="text" name="address"></td>
</tr>
<tr>
<th colspan="2" align="center" ><input type="submit" name="submit" value="添加"></th>
</tr>
<a href="/select" >查询所有学生信息点击此处</a>
</table>
</form>
</body>
</html>
register.jsp
<%--
Created by IntelliJ IDEA.
User: cdk13
Date: 2021/6/7
Time: 20:19
To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>注册</title>
</head>
<body>
<form action="/register" method="post">
<table align="center" border="1 " width="50%" cellpadding="6">
<tr>
<th colspan="2" align="center" >添加新账号</th><%--th加粗， cellpadding和android padding含义一样--%>
</tr>
<tr>
<td align="center" >账号：</td>
<td align="left" ><input type="text" name="name"></td>
</tr>
<tr>
<td align="center" >密码：</td>
<td align="left" ><input type="text" name="pwd1"></td>
</tr>
<tr>
<td align="center" >再次确认密码：</td>
<td align="left" ><input type="text" name="pwd2"></td>
</tr>
<tr>
<th colspan="2" align="center" ><input type="submit" name="submit" value="注册"></th>
</tr>
</table>
</form>
</body>
</html>
success.jsp 登录成功页面
<%--
Created by IntelliJ IDEA.
User: cdk13
Date: 2021/6/7
Time: 23:12
To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>login</title>
注册成功，请回主页面登录<br/>
</head>
<body>
<%response.setHeader("Refresh", "1;index.jsp"); %>
</body>
</html>
> 是因为我之前从all.jsp跳转到这个页面，后面附加了参数id,那么我就知道对应删除的是哪个id的学生信息，由于我这边水平有限，正则表达式和其他方法都不太会，所以采用获得参数,也就是id=？然后截取？,也就知道对应的id，然后给id这个文本框附上对应的文本值,这样就相当于默认值，这样就能修改刚刚指定id的信息，实现jsp-》jsp-》servelt信息的共享 ~~~ <%-- Created by IntelliJ IDEA. User: cdk13 Date: 2021/6/8 Time: 17:02 To change this template use File | Settings | File Templates. --%> <%@ page contentType="text/html;charset=UTF-8" language="java" %>update.jsp
关于这里呢
最后就是关于该实验的不足，由于我是第一次接触还有很多地方没理解到位，这个实验我也是临时肝了三天，基本上就没有怎么休息，因为要一步一步踩坑，避坑，主要的不足在于：1.很多异常处理没有到位，比如说所有界面的文本限制，长度限制 2.界面美化，由于时间不够，临近期末，效果只能说有个雏形 3.一些界面跳转过于敷衍，对于一个jsp实现servlet之间的通信过程有些地方没太理解，比如说可不可以响应多个servlet，所以我特意用超链接避开了，有时间的话我会继续完善的，有什么错误和意见欢迎大家指出。
参考
https://www.cnblogs.com/xin1006/p/11414278.html
https://blog.csdn.net/zs20082012/article/details/79469149
https://blog.csdn.net/weixin_45743799/article/details/103372318