Servlet实现注册登录列表页面及其相互跳转功能
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2022-05-06 13:18:54
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目录
需求
分析
代码实现
- 创建DBUtil工具类
- 创建model包书写students.java代码
- 注册.java代码
- 登录.java代码
- 列表.java代码
- 注册.jsp文件（HTML代码）
- 登录.jsp文件（HTML代码）
- 列表.jsp文件（HTML代码）
- 编写web.xml文件
效果演示
注册页面
登录页面
列表页面
查询数据库数据
需求
注册页面添加登录链接
登录页面添加注册链接
注册成功跳转到登录页面
注册失败跳转到注册页面
登录成功跳转到用户列表页面
登录失败跳转到登录页面
分析
建库建表
一个连接数据库的DBUtil工具类
一个用户列表的model包
注册，登录，用户列表三个.java代码页面
三个.jsp页面
一个web.xml文件
代码实现 - 创建DBUtil工具类
增删改查共同代码
package top.sjh;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException
public class DBUtil {
static{
//1:添加驱动程序
try {
Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
} catch (ClassNotFoundException e) {
e.printStackTrace();
}
}
public static Connection getConn(){
//2:连接数据库
Connection conn = null;
try {
conn = DriverManager.getConnection("jdbc:sqlserver://localhost:1433;databaseName=school", "sa", "1");
} catch (SQLException e) {
e.printStackTrace();
}
return conn;
}
public static void close(Connection conn,PreparedStatement ps,ResultSet rs){
// 7:关闭资源
try {
if(conn != null)
conn.close();
} catch (SQLException e) {
e.printStackTrace();
}
try {
if(ps != null)
ps.close();
} catch (SQLException e) {
e.printStackTrace();
}
try {
if(rs != null)
rs.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
2. 创建model包书写students.java代码
package top.sjh.model;
public class Students {
private Integer id;
private String userName;
private String pwd;
private String name;
private Integer age;
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getUserName() {
return userName;
}
public void setUserName(String userName) {
this.userName = userName;
}
public String getPwd() {
return pwd;
}
public void setPwd(String pwd) {
this.pwd = pwd;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Integer getAge() {
return age;
}
public void setAge(Integer age) {
this.age = age;
}
@Override
public String toString() {
return "<tr>"
+"<td class='left'>"+id+"</td>"
+"<td class='left'>"+userName+"</td>"
+"<td class='left'>"+pwd+"</td>"
+"<td class='left'>"+name+"</td>"
+"<td class='left'>"+age+"</td>"
+"</tr>";
}
public Students(Integer id, String userName, String pwd, String name,
Integer age) {
super();
this.id = id;
this.userName = userName;
this.pwd = pwd;
this.name = name;
this.age = age;
}
public Students( String userName, String pwd, String name,
Integer age) {
super();
this.userName = userName;
this.pwd = pwd;
this.name = name;
this.age = age;
}
public Students() {
super();
// TODO Auto-generated constructor stub
}
}
3. 注册.java代码
Servlet代码+注册页面代码
package top.sjh;
import java.io.;
import java.sql.;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class RegServlet extends HttpServlet {
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doPost(request, response);
}
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
// 1:首先要把编码全部改为utf-8
// 将请求中的编码设置为utf-8
request.setCharacterEncoding("utf-8");
// 将响应中的编码设置为utf-8
response.setCharacterEncoding("utf-8");
// 设置响应的显示格式(类型)
response.setContentType("text/html");
//2:处理请求
String userName = request.getParameter("userName");
String pwd = request.getParameter("pwd");
String name = request.getParameter("name");
String ageStr = request.getParameter("age");
Integer age = Integer.parseInt(ageStr);
// 我们未来将要添加的代码区域
// 注册---> 新增---> insert into book(title,author,classify,versions) values
// (?,?,?,?)
boolean isTrue = false; // 注册是否成功
// 3:添加sql语句
Connection conn = DBUtil.getConn();
String sql = "insert into students(userName,pwd,name,age) values (?,?,?,?)";
// 4:获取结果
PreparedStatement ps = null;
try {
ps = conn.prepareStatement(sql);
ps.setString(1, userName);
ps.setString(2, pwd);
ps.setString(3, name);
ps.setInt(4, age);
// 5:接收结果
int count = ps.executeUpdate();
// 6:输出结果
if (count > 0) {
// 注册成功！
isTrue = true;
}else{
// 注册失败！
isTrue = false;
}
} catch (SQLException e) {
e.printStackTrace();
}
DBUtil.close(conn, ps, null);
//3:处理响应
if (isTrue) {
response.sendRedirect("login.jsp");
}else{
response.sendRedirect("reg.jsp");
}
}
}
4. 登录.java代码
package top.sjh;
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 javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class LoginServlet extends HttpServlet {
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doPost(request, response);
}
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
//1:设置编码问题
// 设置请求的编码问题
request.setCharacterEncoding("utf-8");
//设置响应编码问题
response.setCharacterEncoding("utf-8");
//设置响应的显示格式
response.setContentType("text/html");
//2:处理请求
String userName = request.getParameter("userName");
String pwd = request.getParameter("pwd");
// 验证登录是否成功
boolean isTrue = false;
// 登录业务 --->查询 ---> select * from school where userName=? and pwd=?
//jdbc
Connection conn = DBUtil.getConn();
// 3:添加sql语句
String sql = "select * from students where userName=? and pwd=?";
// 4:获取
PreparedStatement ps = null;
// 5:转换
ResultSet rs = null;
try {
ps = conn.prepareStatement(sql);
ps.setString(1, userName);
ps.setString(2, pwd);
rs = ps.executeQuery();
if (rs.next()) {
isTrue = true;
}else{
isTrue = false;
}
} catch (SQLException e) {
e.printStackTrace();
}
DBUtil.close(conn, ps, rs);
// 处理响应
if (isTrue) {
response.sendRedirect("ListServlet");
}else{
response.sendRedirect("login.jsp");
}
}
}
5. 列表.java代码
package top.sjh;
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.ArrayList;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class ListServlet extends HttpServlet {
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doPost(request, response);
}
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
// 1:首先要把编码全部改为utf-8
// 将请求中的编码设置为utf-8
request.setCharacterEncoding("utf-8");
// 将响应中的编码设置为utf-8
response.setCharacterEncoding("utf-8");
// 设置响应的显示格式(类型)
response.setContentType("text/html");
// 我们未来将要添加的代码区域
// 列表---> 查询---> select * from students
// (?,?,?,?)
// jdbc
//1:添加驱动程序
//2:连接数据库
Connection conn = DBUtil.getConn();
// 3:添加sql语句
String sql = "select * from students";
ArrayList<Students> studentsList = new ArrayList<Students>();
PreparedStatement ps = null;
ResultSet rs = null;
try {
// 4:获取结果
ps = conn.prepareStatement(sql);
// 5:接收结果
rs = ps.executeQuery();
// 6:输出结果
while (rs.next()) {
Students students = new Students();
students.setId(rs.getInt("id"));
students.setUserName(rs.getString("userName"));
students.setPwd(rs.getString("pwd"));
students.setName(rs.getString("name"));
students.setAge(rs.getInt("age"));
studentsList.add(students);
}
//3:处理响应
PrintWriter out = response.getWriter();
out.println("<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\">");
out.println("<HTML>");
out.println(" <HEAD><TITLE>A Servlet</TITLE>");
out.println("<style type=\"text/css\">"
+ ".left{width:100px;text-align: center;}"
+ ".right{width: 200px;}" + "table{margin: 0 auto;}"
+ "th{font-size: 30px;color: red;}" + "td{height: 50px;}"
+ "h1{text-align: center; color:red;font-size: 50px;}</style>");
out.println("</HEAD>");
out.println(" <BODY>");
out.println(" <h1>列表页面</h1>");
// 输出
out.println("<table border=\"1\" cellspacing=\"0\" cellpadding=\"0\">"
+ "<tr>"
+ " <td class=\"left\">编号</td>"
+ " <td class=\"left\">用户名</td>"
+ " <td class=\"left\">密码</td>"
+ " <td class=\"left\">姓名</td>"
+ " <td class=\"left\">年龄</td>"+ "</tr>");
for (Students students : studentsList) {
out.println(students.toString());
}
out.println(" </BODY>");
out.println("</HTML>");
out.flush();
out.close();
} catch (SQLException e) {
e.printStackTrace();
}
// 7:关闭资源
DBUtil.close(conn, ps, rs);
}
}
6. 注册.jsp文件（HTML代码）
<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme() + "://"
+ request.getServerName() + ":" + request.getServerPort()
+ path + "/";
%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<base href="<%=basePath%>">
<title>注册页面</title>
<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="0">
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="This is my page">
<!--
<link rel="stylesheet" type="text/css" href="styles.css">
-->
<style type="text/css">
.model {
text-align: center;
color: red;
font-size: 30px;
}
</style>
</head>
<body>
<div class="model">
<form action="RegServlet" method="post">
<table border="1" cellspacing="0" cellpadding="1" align="center">
注册页面
<tr>
<td><center>账号:</center>
</td>
<td><input type="text" name="userName" />
</td>
</tr>
<tr>
<td><center>密码:</center>
</td>
<td><input type="password" name="pwd" />
</td>
</tr>
<tr>
<td><center>确认密码:</center>
</td>
<td><input type="password" name="pwd" />
</td>
</tr>
<tr>
<td><center>姓名:</center>
</td>
<td><input type="text" name="name" />
</td>
</tr>
<tr>
<td><center>年龄:</center>
</td>
<td><input type="text" name="age" />
</td>
</tr>
<tr>
<td align="center" colspan="2"><input type="submit" value="注册">
<a href='login.jsp'><input type="button" value="登录">
</a></td>
</tr>
</table>
</form>
</div>
</body>
</html>
7. 登录.jsp文件（HTML代码）
<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme() + "://"
+ request.getServerName() + ":" + request.getServerPort()
+ path + "/";
%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<base href="<%=basePath%>">
<title>登录页面</title>
<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="0">
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="This is my page">
<!--
<link rel="stylesheet" type="text/css" href="styles.css">
-->
</head>
<body>
<form action="LoginServlet" method="post">
<table border="1" cellspacing="0" cellpadding="1" align="center">
<h1 style=text-align:center;color:red;>登录页面</h1>
<tr>
<td><center>用户名：</center></td>
<td><input type="text" name="userName"></td>
</tr>
<tr>
<td><center>密码：</center></td>
<td><input type="password" name="pwd"></td>
</tr>
<tr>
<td align="center" colspan="2">
<input type="submit" value="登录" />
<a href="reg.jsp"><input type="button" value="注册"></a>
</td>
</tr>
</table>
</form>
</body>
</html>
8. 列表.jsp文件（HTML代码）
<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme() + "://"
+ request.getServerName() + ":" + request.getServerPort()
+ path + "/";
%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<base href="<%=basePath%>">
<title>用户详情页面</title>
<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="0">
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="This is my page">
<!--
<link rel="stylesheet" type="text/css" href="styles.css">
-->
</head>
<body>
<form action="ListServlet" method="post">
</form>
</body>
</html>
9. 编写web.xml文件
一、手动写入：
二、自动写入（直接new一个Servlet文件）
之后勾选doGet和doPost这两种方法就可以了，点击Next
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