标签:encode lin 另一个 表示 buffer html4 font text math
<%@ page language="java" contentType="text/html; charset=utf-8"
pageEncoding="utf-8"%>
<%!
int count = 0 ;
%>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>Insert title here</title>
</head>
<body>
<h1>你是第<%=++count%>个访问本网站的用户!</h1>
</body>
</html>
Cookie[] cookies = request.getCookies();
Cookie cookie = findCookie(cookies, "lastVisit");
response.setContentType("text/html;charset=utf-8");
if (cookie == null) {
response.getWriter().println("欢迎登录本网站!");
}else{
long lastVisit = Long.parseLong(cookie.getValue());
Date d = new Date(lastVisit);
response.getWriter().println("您上次的访问时间是:"+d.toLocaleString());
}
Cookie c = new Cookie("lastVisit",System.currentTimeMillis()+"");
response.addCookie(c);
// 判断验证码是否正确
String checkcode_session = (String) request.getSession().getAttribute("checkcode_session");
request.getSession().removeAttribute("checkcode_session");
if (checkcode_session == null || !checkcode_session.equals(checkcode)) {
// 验证码输入错误
// 重定向跳回 login.jsp 无法携带信息,转发可以
request.setAttribute("msg", "验证码输入错误!");
request.getRequestDispatcher("/session/login.jsp").forward(request,
response);
return;
}
// 判断用户名和密码是否正确 ,假设用户名和密码都是admin/admin
if ("admin".equals(username) && "admin".equals(password)) {
// 登陆成功
// 将登陆信息保存session
request.getSession().setAttribute("username", username);
response.sendRedirect("/day7/session/welcome.jsp");
} else {
// 登陆失败
request.setAttribute("msg", "用户名或者密码错误!");
request.getRequestDispatcher("/session/login.jsp").forward(request,
response);
}
页面:
<h2 style="color:red;">${requestScope.msg }</h2>
<?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">
<display-name></display-name>
<servlet>
<servlet-name>LastServlet</servlet-name>
<servlet-class>cn.itcast.cookie.LastServlet</servlet-class>
</servlet>
<servlet>
<servlet-name>ProductServlet</servlet-name>
<servlet-class>cn.itcast.cookie.ProductServlet</servlet-class>
</servlet>
<servlet>
<servlet-name>RemoveServlet</servlet-name>
<servlet-class>cn.itcast.cookie.RemoveServlet</servlet-class>
</servlet>
<servlet>
<servlet-name>CartServlet</servlet-name>
<servlet-class>cn.itcast.session.CartServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>LastServlet</servlet-name>
<url-pattern>/servlet/last</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>ProductServlet</servlet-name>
<url-pattern>/product</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>RemoveServlet</servlet-name>
<url-pattern>/remove</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>CartServlet</servlet-name>
<url-pattern>/cart</url-pattern>
</servlet-mapping>
<!-- 验证码 -->
<servlet>
<servlet-name>CheckcodeServlet</servlet-name>
<servlet-class>cn.itcast.session.CheckcodeServlet</servlet-class>
</servlet>
<servlet>
<servlet-name>LoginServlet</servlet-name>
<servlet-class>cn.itcast.session.LoginServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>CheckcodeServlet</servlet-name>
<url-pattern>/checkcode</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>LoginServlet</servlet-name>
<url-pattern>/login</url-pattern>
</servlet-mapping>
<welcome-file-list>
<welcome-file>index.jsp</welcome-file>
</welcome-file-list>
</web-app>
<%@ 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>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
<%!
int a = 10;
%>
<%=a %>
<%
int b = 100;
if(b == 20){
}else{
}
%>
</body>
</html>
<%@ 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>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
<table border="1" width="60%">
<%
for(int i=1;i<=10;i++){
%>
<tr>
<%
for(int j=1;j<=10;j++){
%>
<td>1</td>
<%
}
%>
</tr>
<%
}
%>
</table>
</body>
</html>
3.jsp (熟悉EL表达式)<%@ 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>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
<%
request.setAttribute("aa", "苍老师");
%>
<%= request.getAttribute("aa") %>
${ aa }
</body>
</html>
package cn.itcast.utils;
import javax.servlet.http.Cookie;
/**
* cookie工具类
* @author Administrator
*
*/
public class MyCookieUtil {
/**
* 通过指定名称查找指定的cookie
* @param cookies
* @param name
* @return
*/
public static Cookie getCookieByName(Cookie [] cookies,String name){
// 如果数组是null
if(cookies == null){
return null;
}else{
// 循环遍历,目的:和name进行匹配,如果匹配成功,返回当前的cookie
for (Cookie cookie : cookies) {
// 获取cookie的名称,和name进行匹配
if(cookie.getName().equals(name)){
return cookie;
}
}
return null;
}
}
}
LastServlet.java (判断是否是第一次访问)package cn.itcast.cookie;
import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.Date;
import javax.servlet.ServletException;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import cn.itcast.utils.MyCookieUtil;
/**
* 记录上次的访问时间
* @author Administrator
*
*/
public class LastServlet extends HttpServlet {
private static final long serialVersionUID = -5604481158386227221L;
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
/**
* 1.获取所有的cookie,判断是否是第一次访问
* 2.如果是第一次访问
* * 输出欢迎,记录当前的时间,回写到浏览器
* 3.如果不是第一次访问
* * 获取时间,输出到浏览器,记录当前的时间,回写到浏览器。
* 记录当前的时间,回写到浏览器。
*/
// 设置字符中文乱码问题
response.setContentType("text/html;charset=UTF-8");
// 获取所有的cookie
Cookie [] cookies = request.getCookies();
// 通过指定cookie名称来查找cookie Cookie c = new Cookie("last","当前的时间");
Cookie cookie = MyCookieUtil.getCookieByName(cookies,"last");
// 判断,如果cookie==null,说明是第一次访问
if(cookie == null){
// 输出欢迎,记录当前的时间,回写到浏览器
response.getWriter().write("<h3>亲,欢迎再来哦!!</h3>");
}else{
// 获取cookie的值,输出浏览器,记录当前的时间,回写到浏览器
String value = cookie.getValue();
// 输出浏览器
response.getWriter().write("<h3>亲,您又来了,上次的时间是"+value+"</h3>");
}
// 记录当前的时间
Date date = new Date();
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
String sDate = sdf.format(date);
// 回写到浏览器
// 使用cookie回写
Cookie c = new Cookie("last", sDate);
// 设置有效时间
c.setMaxAge(60*60); // 秒
// 设置有效路径
c.setPath("/day11");
// 回写
response.addCookie(c);
}
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doGet(request, response);
}
}
package cn.itcast.cookie;
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import cn.itcast.utils.MyCookieUtil;
/**
* 浏览记录后台
* @author Administrator
*
*/
public class ProductServlet extends HttpServlet {
private static final long serialVersionUID = -5747737695587699577L;
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
/**
* 1.获取请求参数
* 2.获取cookie数组,通过指定的名称(自己指定)查找cookie
* 3.如果cookie==null,第一次访问
* * 如果是第一次访问,创建cookie,回写浏览器
* 4.如果cookie!=null,不是第一次访问
* * 如果不是第一次访问,说明我的cookie中已经存在id
* * 判断,当前的id是否已经存在cookie的中value
* * 如果存在,不用操作
* * 如果不存在,在后面追加(product=1,2)
* 5.重定向到商品页面
*/
// 获取请求参数 目的:存入到cookie中
String id = request.getParameter("id");
// 先获取所有的cookie,查找指定名称的cookie
Cookie [] cookies = request.getCookies();
// 查找指定名称的cookie
Cookie cookie = MyCookieUtil.getCookieByName(cookies, "product");
// 如果cookie==null,我第一次访问,创建cookie,回写
if(cookie == null){
// 我第一次访问,创建cookie,回写
Cookie c = new Cookie("product", id);
// 设置有效时间 7天
c.setMaxAge(7*24*60*60);
// 设置有效路径
c.setPath("/");
// 回写
response.addCookie(c);
}else{
// 如果不是第一次访问
// 获取cookie的value (value有可能是 1,2,3)
String value = cookie.getValue(); // 1,2,3,4,5
// 判断,当前的商品的id是否包含在value中
String [] values = value.split(",");
if(!checkId(values,id)){
// 不包含
cookie.setValue(value+","+id);
// 设置有效时间 7天
cookie.setMaxAge(7*24*60*60);
// 设置有效路径
cookie.setPath("/");
// 回写
response.addCookie(cookie);
}
}
// 重定向到商品页面
response.sendRedirect("/day11/cookie/productList.jsp");
}
/**
* 判断,当前的id是否包含在values的数组中
* @param values
* @param id
* @return
*/
private boolean checkId(String[] values, String id) {
for (String s : values) {
if(s.equals(id)){
return true;
}
}
return false;
}
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doGet(request, response);
}
}
RemoveServlet.java (请求浏览的商品记录信息,即清除cookie)package cn.itcast.cookie;
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
* 清除cookie
* @author Administrator
*
*/
public class RemoveServlet extends HttpServlet {
private static final long serialVersionUID = 717641936110777278L;
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
// 获取cookie
// 创建Cookie的名称product
Cookie cookie = new Cookie("product", "");
// 设置有效时间
cookie.setMaxAge(0);
// 设置有效路径
cookie.setPath("/");
// 回写
response.addCookie(cookie);
// 重定向商品列表页面
response.sendRedirect("/day11/cookie/productList.jsp");
}
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doGet(request, response);
}
}
<%@page import="cn.itcast.utils.MyCookieUtil"%>
<%@ 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>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
<style type="text/css">
.img1{
width: 160px;
height: 140px;
}
.img2{
width: 80px;
height: 70px;
}
</style>
</head>
<body>
<img class="img1" src="/day11/img/1.jpg"><a href="/day11/product?id=1" >手电筒</a>
<img class="img1" src="/day11/img/2.jpg"><a href="/day11/product?id=2" >电话</a>
<img class="img1" src="/day11/img/3.jpg"><a href="/day11/product?id=3" >电视</a><br/>
<img class="img1" src="/day11/img/4.jpg"><a href="/day11/product?id=4" >冰箱</a>
<img class="img1" src="/day11/img/5.jpg"><a href="/day11/product?id=5" >手表</a>
<img class="img1" src="/day11/img/6.jpg"><a href="/day11/product?id=6" >电脑</a>
<h3>浏览记录</h3>
<h3><a href="/day11/remove">清除记录</a></h3>
<%
// 获取cookie中的value,1,2,3 循环遍历,
Cookie [] cookies = request.getCookies();
// 查找指定名称的cookie
Cookie cookie = MyCookieUtil.getCookieByName(cookies, "product");
// 如果cookie不为空,拿到值,遍历
if(cookie != null){
// 获取值 1,2,3
String value = cookie.getValue();
// 分隔
String [] ids = value.split(",");
// 循环遍历,获取id
for(String id : ids){
%>
<img class="img2" src="/day11/img/<%= id %>.jpg"><br/>
<%
}
}
%>
</body>
</html>
package cn.itcast.session;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
/**
* 购物车后台
* @author Administrator
*
*/
public class CartServlet extends HttpServlet {
private static final long serialVersionUID = -4944571720622706932L;
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
/**
* 1.购物车 Map<String,Integer> cart 把购物车存入session中
* 2.先获取购物车,判断是否是第一次访问
* * 第一次访问:创建购物车,把商品的名称和数量加入到购物车,存入session中
* * 不是第一次访问
* * 判断是否包含该商品,通过名称
* * 如果包含,数量+1 存入session中
* * 如果不包含,存入购物车,存入session中
* 3.继续购物或者结算
*/
// 获取参数
String id = request.getParameter("id");
// 购物车存入商品的名称和数量
String [] names = {"手电筒","冰箱","电视","洗衣机","电脑"};
// 把id翻译名称
int idx = Integer.parseInt(id);
// 商品的名称
String name = names[idx - 1];
// 从session中获取购物车,先获取seesion
HttpSession session = request.getSession();
// 从session中获取购物车
Map<String, Integer> cart = (Map<String, Integer>) session.getAttribute("cart");
// 通过cart进行判断,是否是第一次访问
if(cart == null){
// 创建购物车
cart = new HashMap<String, Integer>();
// 第一次访问
cart.put(name, 1);
// 存入到session中
session.setAttribute("cart", cart);
}else{
// 不是第一次访问,判断是否包含该商品
if(cart.containsKey(name)){
// 包含,取出数量,+1,存入购物车,存入seesion中
// 取出
Integer count = cart.get(name);
count++;
// 购物车存入商品
cart.put(name, count);
// 存入的是购物车
session.setAttribute("cart", cart);
}else{
// 不包含
cart.put(name, 1);
// 存入到seesion中
session.setAttribute("cart", cart);
}
}
// 继续购物或者结算
response.setContentType("text/html;charset=UTF-8");
response.getWriter().write("<h3><a href=‘/day11/session/cartList.jsp‘>继续购物</a> | <a href=‘/day11/session/pay.jsp‘>去结算</a></h3>");
}
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doGet(request, response);
}
}
<%@ 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>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>购物车</title>
</head>
<body>
<h3>手电筒<a href="/day11/cart?id=1">加入购物车</a></h3>
<h3>冰箱<a href="/day11/cart?id=2">加入购物车</a></h3>
<h3>电视<a href="/day11/cart?id=3">加入购物车</a></h3>
<h3>洗衣机<a href="/day11/cart?id=4">加入购物车</a></h3>
<h3>电脑<a href="/day11/cart?id=5">加入购物车</a></h3>
</body>
</html>
<%@page import="java.util.Set"%>
<%@page import="java.util.Map"%>
<%@ 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>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
<h3>结算页面</h3>
<%
// 获取购物车,把购物车中的商品信息和数量显示到页面上
Map<String,Integer> cart = (Map<String,Integer>)request.getSession().getAttribute("cart");
// 购物车不为空,循环遍历
if(cart != null){
// 循环遍历
Set<String> keys = cart.keySet();
// 循环keys,拿到商品的名称
for(String key : keys){
%>
<h3>亲,您购买的商品是<%= key %>,数量是<%= cart.get(key) %></h3>
<%
}
}else{
%>
<h3>亲,您还没有购物,请您去<a href="/day11/session/cartList.jsp">购物</a></h3>
<%
}
%>
</body>
</html>
package cn.itcast.session;
import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics2D;
import java.awt.image.BufferedImage;
import java.io.IOException;
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;
/**
* 验证码(带session校验)
* @author Administrator
*
*/
public class CheckcodeServlet extends HttpServlet {
private static final long serialVersionUID = 8496591097127600779L;
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
/**
* 在内存中生成图片(纸),没有设置背景颜色,画填充的矩形,并且和纸的大小相同,矩形有颜色。
* 获取笔的对象(设置颜色,设置字体,画字符串,画矩形)
* 先准备好数据,随机生成4个字符,把字符画到纸上
* 画干扰线
* 把内存中的图片输出到客户端上
*/
int width = 120;
int height = 30;
// 在内存中生成图片
BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
// 先获取画笔对象
Graphics2D g = (Graphics2D) image.getGraphics();
// 设置灰色
g.setColor(Color.GRAY);
// 画填充的矩形
g.fillRect(0, 0, width, height);
// 设置颜色
g.setColor(Color.BLUE);
// 画边框
g.drawRect(0, 0, width-1, height-1);
// 准备数据,随机获取4个字符
// String words = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz1234567890";
String words = "\u7684\u4e00\u4e86\u662f\u6211\u4e0d\u5728\u4eba\u4eec\u6709\u6765\u4ed6\u8fd9\u4e0a\u7740\u4e2a\u5730\u5230\u5927\u91cc\u8bf4\u5c31\u53bb\u5b50\u5f97\u4e5f\u548c\u90a3\u8981\u4e0b\u770b\u5929\u65f6\u8fc7\u51fa\u5c0f\u4e48\u8d77\u4f60\u90fd\u628a\u597d\u8fd8\u591a\u6ca1\u4e3a\u53c8\u53ef\u5bb6\u5b66\u53ea\u4ee5\u4e3b\u4f1a\u6837\u5e74\u60f3\u751f\u540c\u8001\u4e2d\u5341\u4ece\u81ea\u9762\u524d\u5934\u9053\u5b83\u540e\u7136\u8d70\u5f88\u50cf\u89c1\u4e24\u7528\u5979\u56fd\u52a8\u8fdb\u6210\u56de\u4ec0\u8fb9\u4f5c\u5bf9\u5f00\u800c\u5df1\u4e9b\u73b0\u5c71\u6c11\u5019\u7ecf\u53d1\u5de5\u5411\u4e8b\u547d\u7ed9\u957f\u6c34\u51e0\u4e49\u4e09\u58f0\u4e8e\u9ad8\u624b\u77e5\u7406\u773c\u5fd7\u70b9\u5fc3\u6218\u4e8c\u95ee\u4f46\u8eab\u65b9\u5b9e\u5403\u505a\u53eb\u5f53\u4f4f\u542c\u9769\u6253\u5462\u771f\u5168\u624d\u56db\u5df2\u6240\u654c\u4e4b\u6700\u5149\u4ea7\u60c5\u8def\u5206\u603b\u6761\u767d\u8bdd\u4e1c\u5e2d\u6b21\u4eb2\u5982\u88ab\u82b1\u53e3\u653e\u513f\u5e38\u6c14\u4e94\u7b2c\u4f7f\u5199\u519b\u5427\u6587\u8fd0\u518d\u679c\u600e\u5b9a\u8bb8\u5feb\u660e\u884c\u56e0\u522b\u98de\u5916\u6811\u7269\u6d3b\u90e8\u95e8\u65e0\u5f80\u8239\u671b\u65b0\u5e26\u961f\u5148\u529b\u5b8c\u5374\u7ad9\u4ee3\u5458\u673a\u66f4\u4e5d\u60a8\u6bcf\u98ce\u7ea7\u8ddf\u7b11\u554a\u5b69\u4e07\u5c11\u76f4\u610f\u591c\u6bd4\u9636\u8fde\u8f66\u91cd\u4fbf\u6597\u9a6c\u54ea\u5316\u592a\u6307\u53d8\u793e\u4f3c\u58eb\u8005\u5e72\u77f3\u6ee1\u65e5\u51b3\u767e\u539f\u62ff\u7fa4\u7a76\u5404\u516d\u672c\u601d\u89e3\u7acb\u6cb3\u6751\u516b\u96be\u65e9\u8bba\u5417\u6839\u5171\u8ba9\u76f8\u7814\u4eca\u5176\u4e66\u5750\u63a5\u5e94\u5173\u4fe1\u89c9\u6b65\u53cd\u5904\u8bb0\u5c06\u5343\u627e\u4e89\u9886\u6216\u5e08\u7ed3\u5757\u8dd1\u8c01\u8349\u8d8a\u5b57\u52a0\u811a\u7d27\u7231\u7b49\u4e60\u9635\u6015\u6708\u9752\u534a\u706b\u6cd5\u9898\u5efa\u8d76\u4f4d\u5531\u6d77\u4e03\u5973\u4efb\u4ef6\u611f\u51c6\u5f20\u56e2\u5c4b\u79bb\u8272\u8138\u7247\u79d1\u5012\u775b\u5229\u4e16\u521a\u4e14\u7531\u9001\u5207\u661f\u5bfc\u665a\u8868\u591f\u6574\u8ba4\u54cd\u96ea\u6d41\u672a\u573a\u8be5\u5e76\u5e95\u6df1\u523b\u5e73\u4f1f\u5fd9\u63d0\u786e\u8fd1\u4eae\u8f7b\u8bb2\u519c\u53e4\u9ed1\u544a\u754c\u62c9\u540d\u5440\u571f\u6e05\u9633\u7167\u529e\u53f2\u6539\u5386\u8f6c\u753b\u9020\u5634\u6b64\u6cbb\u5317\u5fc5\u670d\u96e8\u7a7f\u5185\u8bc6\u9a8c\u4f20\u4e1a\u83dc\u722c\u7761\u5174\u5f62\u91cf\u54b1\u89c2\u82e6\u4f53\u4f17\u901a\u51b2\u5408\u7834\u53cb\u5ea6\u672f\u996d\u516c\u65c1\u623f\u6781\u5357\u67aa\u8bfb\u6c99\u5c81\u7ebf\u91ce\u575a\u7a7a\u6536\u7b97\u81f3\u653f\u57ce\u52b3\u843d\u94b1\u7279\u56f4\u5f1f\u80dc\u6559\u70ed\u5c55\u5305\u6b4c\u7c7b\u6e10\u5f3a\u6570\u4e61\u547c\u6027\u97f3\u7b54\u54e5\u9645\u65e7\u795e\u5ea7\u7ae0\u5e2e\u5566\u53d7\u7cfb\u4ee4\u8df3\u975e\u4f55\u725b\u53d6\u5165\u5cb8\u6562\u6389\u5ffd\u79cd\u88c5\u9876\u6025\u6797\u505c\u606f\u53e5\u533a\u8863\u822c\u62a5\u53f6\u538b\u6162\u53d4\u80cc\u7ec6";
// 设置颜色
g.setColor(Color.YELLOW);
// 设置字体
g.setFont(new Font("隶书", Font.BOLD, 20));
StringBuffer sb = new StringBuffer();
Random random = new Random();
int x = 20;
int y = 20;
for(int i=0;i<4;i++){
// void rotate(double theta, double x, double y)
// theta 弧度
// hudu = jiaodu * Math.PI / 180;
// 获取正负30之间的角度
int jiaodu = random.nextInt(60)-30;
double hudu = jiaodu * Math.PI / 180;
g.rotate(hudu, x, y);
// 获取下标
int index = random.nextInt(words.length());
// 返回指定下标位置的字符,随机获取下标
char ch = words.charAt(index);
// 把ch装起来,存入到session中
sb.append(ch);
// 写字符串
g.drawString(""+ch, x, y);
g.rotate(-hudu, x, y);
x += 20;
}
// 存入session中
//HttpSession session = request.getSession();
//session.setAttribute("code", sb.toString());
request.getSession().setAttribute("code", sb.toString());
//String str = (String) session.getAttribute("code");
//System.out.println(str);
// 设置颜色
g.setColor(Color.GREEN);
int x1,x2,y1,y2;
// 画干扰线
for(int i=0;i<4;i++){
x1 = random.nextInt(width);
y1 = random.nextInt(height);
x2 = random.nextInt(width);
y2 = random.nextInt(height);
g.drawLine(x1, y1, x2, y2);
}
// 输出到客户端
ImageIO.write(image, "jpg", response.getOutputStream());
}
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doGet(request, response);
}
public static void main(String[] args) {
System.out.println("\u9fa5");
System.out.println("\u9fa4");
System.out.println("\u9fa3");
System.out.println("\u9fa2");
}
}
package cn.itcast.session;
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
/**
* 校验验证码
* @author Administrator
*
*/
public class LoginServlet extends HttpServlet {
private static final long serialVersionUID = 5683537422566655209L;
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
// 解决post请求中文乱码的问题
request.setCharacterEncoding("UTF-8");
//HttpSession session = request.getSession();
// 获取session中验证码
//String code1 = (String) session.getAttribute("code");
String code1 = (String) request.getSession().getAttribute("code");
System.out.println(code1);
// 获取表单中的验证码
String code2 = request.getParameter("code");
// 是否相同
if(code2 != null && code1.equals(code2)){
response.getWriter().write("success");
}else{
// 如果不相同,返回错误的信息
// 转发
request.setAttribute("msg", "验证码输入错误");
request.getRequestDispatcher("/session/login.jsp").forward(request, response);
}
}
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doGet(request, response);
}
}
<%@ 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>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
${msg }
<form action="/day11/login" method="post">
<table border="1" width="70%">
<tr>
<td>输入姓名</td>
<td>
<input type="text" name="username" />
</td>
</tr>
<tr>
<td>输入密码</td>
<td>
<input type="password" name="password" />
</td>
</tr>
<tr>
<td>验证码</td>
<td>
<input type="text" name="code" />
<img id="imgId" src="/day11/checkcode">
<a href="#" onclick="run()">看不清,换一张</a>
</td>
</tr>
<tr>
<td colspan="2">
<input type="submit" value="登陆"/>
</td>
</tr>
</table>
</form>
</body>
<script type="text/javascript">
// 看不清,换一张,时间戳
function run(){
// 获取图片
var image = document.getElementById("imgId");
image.src = "/day11/checkcode?"+new Date().getTime();
}
</script>
</html>
JAVAWEB开发之JSP、EL、及会话技术(Cookie和Session)的使用详解
标签:encode lin 另一个 表示 buffer html4 font text math
原文地址:http://blog.csdn.net/u013087513/article/details/54629226