web实现图形验证码功能
这里直接上工程文件源码：
ValidateImage.java:
package jpeg; 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.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import com.sun.image.codec.jpeg.JPEGCodec; import com.sun.image.codec.jpeg.JPEGEncodeParam; import com.sun.image.codec.jpeg.JPEGImageEncoder; public class ValidateImage extends HttpServlet { protected void doGet(HttpServletRequest request,HttpServletResponse response) throws ServletException,IOException{ response.setContentType("image/jpeg"); createImage(response.getOutputStream()); response.setHeader("Pragma","No-cache"); response.setHeader("Cache-Control","no-cache"); response.setDateHeader("Expires", 0); } private void createImage(OutputStream out)throws IOException { int width=60, height=20; 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(0, 0, width, height); g.setFont(new Font("Times New Roman",1,15)); //g.setColor(new Color()); //g.drawRect(0,0,width-1,height-1); g.setColor(getRandColor(160,200)); for (int i=0;i<155;i++){ int x = random.nextInt(width); int y = random.nextInt(height); int xl = random.nextInt(12); int yl = random.nextInt(12); g.drawLine(x,y,x+xl,y+yl); } //String rand = request.getParameter("rand"); //rand = rand.substring(0,rand.indexOf(".")); String sRand=""; for (int i=0;i<4;i++){ String rand=String.valueOf(random.nextInt(10)); sRand+=rand; g.setColor(new Color(20+random.nextInt(110),20+random.nextInt(110),20+random.nextInt(110))); g.drawString(rand,13*i+6,16); } //session.setAttribute("rand",sRand); g.dispose(); JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(out); JPEGEncodeParam param = encoder.getDefaultJPEGEncodeParam(image); param.setQuality(1.0f, false); encoder.setJPEGEncodeParam(param); try{ encoder.encode(image); }catch (IOException ioe){ ioe.printStackTrace(); } } 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); } }
TestImage.jsp:
<body> <img src="validate"> <br> </body>
web.xml:
<?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> <description>This is the description of my J2EE component</description> <display-name>This is the display name of my J2EE component</display-name> <servlet-name>ValidateImage</servlet-name> <servlet-class>jpeg.ValidateImage</servlet-class> </servlet> <servlet-mapping> <servlet-name>ValidateImage</servlet-name> <url-pattern>/validate</url-pattern> </servlet-mapping> <welcome-file-list> <welcome-file>index.jsp</welcome-file> </welcome-file-list> </web-app>
地址栏：http://localhost:8080/JPEG/jsp/TestImage.jsp 结果：
来自：http://blog.csdn.net/itzyjr/article/details/8451994
本文由用户 jopen 自行上传分享，仅供网友学习交流。所有权归原作者，若您的权利被侵害，请联系管理员。
转载本站原创文章，请注明出处，并保留原始链接、图片水印。
本站是一个以用户分享为主的开源技术平台，欢迎各类分享！