session 用户密码验证码登录
ServletJsp20151021学习笔记
entity.User.java
package entity;
public class User {
private int id;
private String username;
private String pwd;
private String name;
private String gender;
public User() {
// TODO Auto-generated constructor stub
}
public int getId() {
return id;
}
public void setId(int 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 String getGender() {
return gender;
}
public void setGender(String gender) {
this.gender = gender;
}
public User(int id, String username, String pwd, String name, String gender) {
super();
this.id = id;
this.username = username;
this.pwd = pwd;
this.name = name;
this.gender = gender;
}
@Override
public String toString() {
return "user [id=" + id + ", username=" + username + ", pwd=" + pwd
+ ", name=" + name + ", gender=" + gender + "]";
}
}
dao.DBUtil.java
package dao;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
public class DBUtil {
public static Connection getConnection() throws Exception{
Connection conn=null;
try {
Class.forName("com.mysql.jdbc.Driver");
conn = DriverManager.
getConnection(
"jdbc:mysql://localhost:3306/leemamas?useUnicode=true&characterEncoding=utf8",
"root", "");
} catch (Exception e) {
e.printStackTrace();
throw e;
}
return conn;
}
public static void closeConnection(Connection conn)throws Exception{
if(conn!=null){
try {
conn.close();
} catch (SQLException e) {
e.printStackTrace();
throw e;
}
}
}
public static void main(String[] args) throws Exception {
System.out.println(getConnection());
}
}
package dao;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import entity.User;
public class UserDAO {
public User findByUsername(String username) throws Exception{
User user=null;
Connection conn=null;
PreparedStatement stmt=null;
ResultSet rs=null;
try {
conn=DBUtil.getConnection();
String sql="select * from user where username=?";
stmt=conn.prepareStatement(sql);
stmt.setString(1, username);
rs=stmt.executeQuery();
if(rs.next()){
user=new User();
user.setId(rs.getInt("id"));
user.setUsername(username);
user.setPwd(rs.getString("pwd"));
user.setName(rs.getString("name"));
user.setGender(rs.getString("gender"));
}
} catch (Exception e) {
e.printStackTrace();
throw e;
}finally{
DBUtil.closeConnection(conn);
}
return user;
}
}
web.ValidateCode
package web;
import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.util.Random;
import javax.imageio.ImageIO;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import com.sun.org.apache.commons.digester.rss.Image;
public class ValidateCode extends HttpServlet {
public void service(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
//画布
BufferedImage image=new BufferedImage(90,30,BufferedImage.TYPE_INT_RGB);
//画笔
Graphics g=image.getGraphics();
//设置颜色
g.setColor(new Color(255,255,255));
//设置背景
g.fillRect(0, 0, 90, 30);
//重射画笔颜色
Random ran=new Random();
g.setColor( new Color(ran.nextInt(255),ran.nextInt(255),ran.nextInt(255)));
//随机数/./..
String num=getNumber(5);
//绑定session
HttpSession session=request.getSession();
session.setAttribute("num", num);
g.setFont(new Font(null,Font.BOLD,24));
//验证码转化图片
g.drawString(num, 5, 25);
//干扰线
for(int i=0;i<8;i++){
g.setColor( new Color(ran.nextInt(255),ran.nextInt(255),ran.nextInt(255)));
g.drawLine(ran.nextInt(90),ran.nextInt(30),ran.nextInt(90), ran.nextInt(30));
}
//服务器返回数据类型
response.setContentType("image/jpeg");
//输出流
OutputStream os=response.getOutputStream();
ImageIO.write(image, "jpeg", os);
os.close();
}
public String getNumber(int size){
String num="";
String str="ABCDEFGHJKLMNPQRSTUVWXYZ23456789";
Random ran=new Random();
for(int i=0;i<size;i++){
num+=str.charAt(ran.nextInt(str.length()));
}
return num;
}
}
package web;
import java.io.IOException;
import javax.jms.Session;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import dao.UserDAO;
import entity.User;
public class ActionServlet extends HttpServlet {
public void service(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
request.setCharacterEncoding("utf-8"); //字符控制
String uri = request.getRequestURI();
String action =uri.substring(uri.lastIndexOf("/")+1,uri.lastIndexOf(".")); //地址判断
if("login".equals(action)){
String code=request.getParameter("code"); //输入验证码
HttpSession session = request.getSession();
String num=(String)session.getAttribute("num"); //随机生成码
if(!code.equalsIgnoreCase(num)){ //判断验证码
request.setAttribute("code_error", "Code error!");
request.getRequestDispatcher("login.jsp").forward(request, response);
return;
}
String username =request.getParameter("username"); //读取用户名和密码
String pwd =request.getParameter("pwd");
UserDAO dao = new UserDAO(); //查数据库相应记录
try {
User user = dao.findByUsername(username);
if(user != null&& user.getPwd().equals(pwd)){ //判断用户名和密码
session.setMaxInactiveInterval(60); //session死亡时间60秒
session.setAttribute("user", username); //绑定用户名到seesion
response.sendRedirect("index.jsp"); //正确返回主页
}else{
request.setAttribute("login_failed","User or Pwd error!"); //登录失败提示
request.getRequestDispatcher("login.jsp").forward(request, response);
}
} catch (Exception e) {
e.printStackTrace();
throw new ServletException(e);
}
}else if("logout".equals(action)){ //用户登出
HttpSession session=request.getSession();
session.invalidate();
response.sendRedirect("login.jsp");
}
}
}
<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5"
xmlns="http://java.sun.com/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
<servlet>
<servlet-name>ActionServlet</servlet-name>
<servlet-class>web.ActionServlet</servlet-class>
</servlet>
<servlet>
<servlet-name>ValidateCode </servlet-name>
<servlet-class>web.ValidateCode</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>ActionServlet</servlet-name>
<url-pattern>*.do</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>ValidateCode </servlet-name>
<url-pattern>/code</url-pattern>
</servlet-mapping>
<welcome-file-list>
<welcome-file>index.jsp</welcome-file>
</welcome-file-list>
</web-app>
<%@page pageEncoding="utf-8" contentType="text/html; charset=utf-8"%>
<html>
<head>
<style type="text/css">
.s1{
cursor: pointer;
}
</style>
</head>
<body style="font-size:30px">
<form action="login.do" method="post">
<fieldset>
<legend>Login</legend>
username:<input name="username">
<%
String msg=(String)request.getAttribute("login_failed");
%>
<span style="color:red"><%=(msg==null?"":msg)%></span>
<br/>
pwd: <input type="password" name="pwd"><br/>
Code： <input name="code">
<%
String msg2=(String)request.getAttribute("code_error");
%>
<img src="code" onclick="this.src='code?'+Math.random();" class="s1" title="change">
<span style="color:red"><%=(msg2==null?"":msg2)%></span>
<br/>
<input type="submit" value="Login" >
</fieldset>
</form>
</body>
</html>
<%@page contentType="text/html; charset=utf-8" pageEncoding="utf-8"%>
<%
Object user=session.getAttribute("user");
if(user==null){
response.sendRedirect("login.jsp");
return;
}
%>
<html>
<head></head>
<body>
<h1><%=user.toString() %>，</h3>登录成功！<br/><br/>
<a href="logout.do">Logout</a>
</body>
</html>
lib库导入mysql驱动包！