跪求 java 验证码 !!! 验证码java 解决方案 » 免费领取超大流量手机卡,每月29元包185G流量+100分钟通话, 中国电信官方发货 <%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%><!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"><html> <head> <title>验证码</title> <script type="text/javascript"> function refresh(obj) { obj.src = "imageServlet?"+Math.random(); } </script> </head> <body> <form action="checkServlet" method="post"> <label>输入验证码</label><br/> <input type="text" name="randomCode"/><img title="点击更换" onclick="javascript:refresh(this);" src="imageServlet"><br/> <input type="submit" value="submit"> </form> </body></html>package com.test.ourfunture;import java.io.IOException;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;public class ImageServlet extends HttpServlet { private static final long serialVersionUID = 1L; public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { response.setContentType("image/jpeg");//设置相应类型,告诉浏览器输出的内容为图片 response.setHeader("Pragma", "No-cache");//设置响应头信息,告诉浏览器不要缓存此内容 response.setHeader("Cache-Control", "no-cache"); response.setDateHeader("Expire", 0); RandomValidateCode randomValidateCode = new RandomValidateCode(); try { randomValidateCode.getRandcode(request, response);//输出图片方法 } catch (Exception e) { e.printStackTrace(); } } public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doGet(request, response); }}package com.test.ourfunture;import java.awt.Color;import java.awt.Font;import java.awt.Graphics;import java.awt.image.BufferedImage;import java.util.Random;import javax.imageio.ImageIO;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import javax.servlet.http.HttpSession;public class RandomValidateCode { public static final String RANDOMCODEKEY = "RANDOMVALIDATECODEKEY";//放到session中的key private Random random = new Random(); private String randString = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";//随机产生的字符串 private int width = 80;//图片宽 private int height = 26;//图片高 private int lineSize = 40;//干扰线数量 private int stringNum = 4;//随机产生字符数量 /* * 获得字体 */ private Font getFont(){ return new Font("Fixedsys",Font.CENTER_BASELINE,18); } /* * 获得颜色 */ private Color getRandColor(int fc,int bc){ if(fc > 255) fc = 255; if(bc > 255) bc = 255; int r = fc + random.nextInt(bc-fc-16); int g = fc + random.nextInt(bc-fc-14); int b = fc + random.nextInt(bc-fc-18); return new Color(r,g,b); } /** * 生成随机图片 */ public void getRandcode(HttpServletRequest request, HttpServletResponse response) { HttpSession session = request.getSession(); //BufferedImage类是具有缓冲区的Image类,Image类是用于描述图像信息的类 BufferedImage image = new BufferedImage(width,height,BufferedImage.TYPE_INT_BGR); Graphics g = image.getGraphics();//产生Image对象的Graphics对象,改对象可以在图像上进行各种绘制操作 g.fillRect(0, 0, width, height); g.setFont(new Font("Times New Roman",Font.ROMAN_BASELINE,18)); g.setColor(getRandColor(110, 133)); //绘制干扰线 for(int i=0;i<=lineSize;i++){ drowLine(g); } //绘制随机字符 String randomString = ""; for(int i=1;i<=stringNum;i++){ randomString=drowString(g,randomString,i); } session.removeAttribute(RANDOMCODEKEY); session.setAttribute(RANDOMCODEKEY, randomString); System.out.println(randomString); g.dispose(); try { ImageIO.write(image, "JPEG", response.getOutputStream());//将内存中的图片通过流动形式输出到客户端 } catch (Exception e) { e.printStackTrace(); } } /* * 绘制字符串 */ private String drowString(Graphics g,String randomString,int i){ g.setFont(getFont()); g.setColor(new Color(random.nextInt(101),random.nextInt(111),random.nextInt(121))); String rand = String.valueOf(getRandomString(random.nextInt(randString.length()))); randomString +=rand; g.translate(random.nextInt(3), random.nextInt(3)); g.drawString(rand, 13*i, 16); return randomString; } /* * 绘制干扰线 */ private void drowLine(Graphics g){ int x = random.nextInt(width); int y = random.nextInt(height); int xl = random.nextInt(13); int yl = random.nextInt(15); g.drawLine(x, y, x+xl, y+yl); } /* * 获取随机的字符 */ public String getRandomString(int num){ return String.valueOf(randString.charAt(num)); }}<?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>ImageServlet</servlet-name> <servlet-class>com.test.ourfunture.ImageServlet</servlet-class> </servlet> <servlet-mapping> <servlet-name>ImageServlet</servlet-name> <url-pattern>/imageServlet</url-pattern> </servlet-mapping> <welcome-file-list> <welcome-file>index.jsp</welcome-file> </welcome-file-list></web-app> 这种功能需求不复杂啊,楼主完全可以自己写出来的,核心是画干扰线条,Java绘图API就可以搞定的 Java教程 清空UploadFile组件? 关于groovy的一个语法的疑问 按钮不会失效。。。 关于String.getBytes()的一些疑问 MyEclipse 7.0里面能写javascript吗!为什么我写了运行得不到任何效果?是不是和Macromedia Dreamweaver 8一样的写法?? 请大哥大姐帮忙说下一个好的jsp网站应注意哪些问题(由政府网站经验的尤其欢迎),来者有分,绝不食言。。。。 写入数据库中时中文的问题! 请问JavaBean和servlet有什么区别吗? 关于ajax回调函数data的问题 排序问题 使用AJAX实现省份和城市级联显示的问题
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>验证码</title>
<script type="text/javascript">
function refresh(obj) {
obj.src = "imageServlet?"+Math.random();
}
</script>
</head>
<body>
<form action="checkServlet" method="post">
<label>输入验证码</label><br/>
<input type="text" name="randomCode"/><img title="点击更换" onclick="javascript:refresh(this);" src="imageServlet"><br/>
<input type="submit" value="submit">
</form>
</body>
</html>package com.test.ourfunture;import java.io.IOException;import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;public class ImageServlet extends HttpServlet { private static final long serialVersionUID = 1L; public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException { response.setContentType("image/jpeg");//设置相应类型,告诉浏览器输出的内容为图片
response.setHeader("Pragma", "No-cache");//设置响应头信息,告诉浏览器不要缓存此内容
response.setHeader("Cache-Control", "no-cache");
response.setDateHeader("Expire", 0);
RandomValidateCode randomValidateCode = new RandomValidateCode();
try {
randomValidateCode.getRandcode(request, response);//输出图片方法
} catch (Exception e) {
e.printStackTrace();
}
} public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doGet(request, response);
}}
package com.test.ourfunture;
import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.util.Random;import javax.imageio.ImageIO;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;public class RandomValidateCode { public static final String RANDOMCODEKEY = "RANDOMVALIDATECODEKEY";//放到session中的key
private Random random = new Random();
private String randString = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";//随机产生的字符串
private int width = 80;//图片宽
private int height = 26;//图片高
private int lineSize = 40;//干扰线数量
private int stringNum = 4;//随机产生字符数量
/*
* 获得字体
*/
private Font getFont(){
return new Font("Fixedsys",Font.CENTER_BASELINE,18);
}
/*
* 获得颜色
*/
private Color getRandColor(int fc,int bc){
if(fc > 255)
fc = 255;
if(bc > 255)
bc = 255;
int r = fc + random.nextInt(bc-fc-16);
int g = fc + random.nextInt(bc-fc-14);
int b = fc + random.nextInt(bc-fc-18);
return new Color(r,g,b);
}
/**
* 生成随机图片
*/
public void getRandcode(HttpServletRequest request,
HttpServletResponse response) {
HttpSession session = request.getSession();
//BufferedImage类是具有缓冲区的Image类,Image类是用于描述图像信息的类
BufferedImage image = new BufferedImage(width,height,BufferedImage.TYPE_INT_BGR);
Graphics g = image.getGraphics();//产生Image对象的Graphics对象,改对象可以在图像上进行各种绘制操作
g.fillRect(0, 0, width, height);
g.setFont(new Font("Times New Roman",Font.ROMAN_BASELINE,18));
g.setColor(getRandColor(110, 133));
//绘制干扰线
for(int i=0;i<=lineSize;i++){
drowLine(g);
}
//绘制随机字符
String randomString = "";
for(int i=1;i<=stringNum;i++){
randomString=drowString(g,randomString,i);
}
session.removeAttribute(RANDOMCODEKEY);
session.setAttribute(RANDOMCODEKEY, randomString);
System.out.println(randomString);
g.dispose();
try {
ImageIO.write(image, "JPEG", response.getOutputStream());//将内存中的图片通过流动形式输出到客户端
} catch (Exception e) {
e.printStackTrace();
}
}
/*
* 绘制字符串
*/
private String drowString(Graphics g,String randomString,int i){
g.setFont(getFont());
g.setColor(new Color(random.nextInt(101),random.nextInt(111),random.nextInt(121)));
String rand = String.valueOf(getRandomString(random.nextInt(randString.length())));
randomString +=rand;
g.translate(random.nextInt(3), random.nextInt(3));
g.drawString(rand, 13*i, 16);
return randomString;
}
/*
* 绘制干扰线
*/
private void drowLine(Graphics g){
int x = random.nextInt(width);
int y = random.nextInt(height);
int xl = random.nextInt(13);
int yl = random.nextInt(15);
g.drawLine(x, y, x+xl, y+yl);
}
/*
* 获取随机的字符
*/
public String getRandomString(int num){
return String.valueOf(randString.charAt(num));
}
}<?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>ImageServlet</servlet-name>
<servlet-class>com.test.ourfunture.ImageServlet</servlet-class>
</servlet> <servlet-mapping>
<servlet-name>ImageServlet</servlet-name>
<url-pattern>/imageServlet</url-pattern>
</servlet-mapping>
<welcome-file-list>
<welcome-file>index.jsp</welcome-file>
</welcome-file-list>
</web-app>