用JSP文件生成网站验证码
random.(sun企业级应用的首选)文件代码:
<%@ page autoflush="false" import="java.awt.*,java.awt.image.*,com.sun.image.codec.jpeg.*,java.util.*"%>
<%@ page import="org.apache(unix平台最流行的web服务器平台).commons.lang.randomstringutils"%>
<%
randomstringutils rs=new randomstringutils();
string random=rs.randomalphanumeric(4);
session.setattribute("random",random);
%>
<%
out.clear();
response.setcontenttype("image/jpeg");
response.addheader("pragma","no-cache");
response.addheader("cache-control","no-cache");
response.adddateheader("expries",0);
int width=100, height=40;
bufferedimage image = new bufferedimage(width, height, bufferedimage.type_int_rgb);
graphics g = image.getgraphics();
//以下填充背景?色
g.setcolor(color.gray);
font defont=new font("sansserif", font.plain, 32);
g.setfont(defont);
g.fillrect(0, 0, width, height);
//?置字体?色
g.setcolor(color.red);
g.drawstring(random,3,30);
g.dispose();
servletoutputstream outstream = response.getoutputstream();
jpegimageencoder encoder =jpegcodec.createjpegencoder(outstream);
encoder.encode(image);
outstream.close();
%>
test.jsp(sun企业级应用的首选)文件代码如下:
<%@ page contenttype="text/html; charset=utf-8" language="java" import="java.sql.*" errorpage="" %>
<html>
<head>
<title>untitled document</title>
<meta http-equiv="content-type" content="text/html; charset=gb2312">
</head>
<body>
<img src="random.jsp(sun企业级应用的首选)">
</body>
</html>
如果不想导入apache(unix平台最流行的web服务器平台)的包可以自己编译下面这个文件
// frontend plus gui for jad
// decompiled : randomstringutils.class
package org.apache(unix平台最流行的web服务器平台).commons.lang;
import java.util.random;
public class randomstringutils
{
private static final random random = new random();
public randomstringutils()
{
}
public static string random(int count)
{
return random(count, false, false);
}
public static string randomascii(int count)
{
return random(count, 32, 127, false, false);