验证码不显示
<%@ page language="java" import="java.util.*" contentType="text/html; charset=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">
-->
</head>
<body>
验证码：<input type="text" name = "checkcode"/>
<img alt="验证码" src="<%= request.getContextPath();%>/servlet/ImageServlet"/>
<<a href="javascript:reloadCode();">看不清楚</a><br>
</body>
</html>
package com.Servlet;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.util.Random;
import javax.imageio.ImageIO;
import javax.imageio.spi.ImageWriterSpi;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class ImageServlet extends HttpServlet {
public void doGet( HttpServletRequest request,HttpServletResponse response){
BufferedImage bi = new BufferedImage(68, 26,BufferedImage.TYPE_INT_RGB);
Graphics g = bi.getGraphics();
Color c = new Color(200, 150, 255);
g.setColor(c);
g.fillRect(0, 0, 68, 26);
char[] ch = "ABCDEFGHIJKLMNOPQRSTUVWXYZ123456789".toCharArray();
Random r = new Random();
int len = ch.length,index;
StringBuffer sb = new StringBuffer();
for (int i = 0; i <4; i++) {
index = r.nextInt(len);
g.setColor(new Color(r.nextInt(88),r.nextInt(188),r.nextInt(255)));
g.drawString(ch[index]+" ", (i*15)+3,18 );
sb.append(ch[index]);
}
request.getSession().setAttribute("piccode",sb.toString() );
try {
ImageIO.write(bi, "JPG", response.getOutputStream());
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
