AuthImageServlet.java
package com.util.servlet;
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.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;
public class AuthImageServlet extends HttpServlet {
/**
* Constructor of the object.
*/
private static final String CONTENT_TYPE = "text/html; charset=gb2312";
//设置字母的大小,大小
private Font mFont = new Font("Times New Roman", Font.PLAIN, 17);
public void init() throws ServletException
{
super.init();
}
Color getRandColor(int fc,int bc)
{
Random random = new Random();
if(fc>255) fc=255;
if(bc>255) bc=255;
int r=fc+random.nextInt(bc-fc);
int g=fc+random.nextInt(bc-fc);
int b=fc+random.nextInt(bc-fc);
return new Color(r,g,b);
}
public void service(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException
{
response.setHeader("Pragma","No-cache");
response.setHeader("Cache-Control","no-cache");
response.setDateHeader("Expires", 0);
//表明生成的响应是图片
response.setContentType("image/jpeg");
int width=100, height=18;
BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
Graphics g = image.getGraphics();
Random random = new Random();
g.setColor(getRandColor(200,250));
g.fillRect(1, 1, width-1, height-1);
g.setColor(new Color(102,102,102));
g.drawRect(0, 0, width-1, height-1);
g.setFont(mFont);
g.setColor(getRandColor(160,200));
//画随机线
for (int i=0;i<155;i++)
{
int x = random.nextInt(width - 1);
int y = random.nextInt(height - 1);
int xl = random.nextInt(6) + 1;
int yl = random.nextInt(12) + 1;
g.drawLine(x,y,x + xl,y + yl);
}
//从另一方向画随机线
for (int i = 0;i < 70;i++)
{
int x = random.nextInt(width - 1);
int y = random.nextInt(height - 1);
int xl = random.nextInt(12) + 1;
int yl = random.nextInt(6) + 1;
g.drawLine(x,y,x - xl,y - yl);
}
//生成随机数,并将随机数字转换为字母
String codeList = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz1234567890";
String sRand="";
for (int i=0;i<6;i++){
int a=random.nextInt(codeList.length()-1);
String rand=codeList.substring(a,a+1);
sRand+=rand;
g.setColor(new Color(20+random.nextInt(110),20+random.nextInt(110),20+random.nextInt(110)));
g.drawString(rand,15*i+10,16);
}
System.out.println("-----------------------------------"+sRand);
HttpSession session = request.getSession(true);
session.setAttribute("rand",sRand);
g.dispose();
OutputStream os =response.getOutputStream();
ImageIO.write(image, "JPEG", os);
}
}
CheckServlet.java
package com.util.servlet;
import java.io.IOException;
import java.io.PrintWriter;
import javax.mail.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;
public class CheckServlet extends HttpServlet {
/**
* Constructor of the object.
*/
public CheckServlet() {
super();
}
/**
* Destruction of the servlet. <br>
*/
public void destroy() {
super.destroy(); // Just puts "destroy" string in log
// Put your code here
}
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
this.doPost(request, response);
}
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
request.setCharacterEncoding("utf-8");
String yzm=request.getParameter("yzm");
HttpSession session=request.getSession(true);
String xt=session.getAttribute("rand").toString();
if(yzm.equals(xt)){
System.out.println("验证码相同");
}else{
System.out.println("验证码不同11111111111111111111");
}
System.out.println("yzm："+yzm);
System.out.println("XT："+xt);
//string account = context.Session["rand"].ToString();
//String user = session.getAttribute("rand");
}
/**
* Initialization of the servlet. <br>
*
* @throws ServletException if an error occurs
*/
public void init() throws ServletException {
// Put your code here
}
}
index.jsp
<%@ 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>My JSP 'index.jsp' starting page</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">
-->
<script type="text/javascript">
function changeCode() {
var imgNode = document.getElementById("vimg");
imgNode.src="servlet/AuthImageServlet?"+Math.random();
}
</script>
</head>
<body>
<form action="servlet/CheckServlet" method="post">
<label>输入验证码</label><br>
<input type="text" name="yzm"/><img alt="yzm" id="vimg" title="点击更换" onclick="changeCode()"
src="servlet/AuthImageServlet"><br>
<input type="submit" name="submit"/>
</form>
This is my JSP page. <br>
</body>
</html>
