Java生成图片验证码

1、 import java.io.*; import .*; import javax.servlet.*; import javax.servlet.http.*; import java.awt.*; import java.awt.image.*; import java.util.*; import javax.imageio.*; /* * * author * version */ public class Image extends HttpServlet /* Processes requests for both HTTP <code

2、>GET</code> and <code>POST</code> methods. * param request servlet request * param response servlet response */ protected void processRequest(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException response.setContentType("image/jpeg&q

3、uot;); response.setHeader("Pragma","No-cache"); response.setHeader("Cache-Control","no-cache"); response.setDateHeader("Expires", 0); HttpSession session=request.getSession(); / ÔÚÄÚ´æÖд´½¨

4、ͼÏó int width=60, height=20; BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB); / »ñȡͼÐÎÉÏÏÂÎÄ Graphics g = image.getGraphics(); /Éú³ÉËæ»&#

5、250;Àà Random random = new Random(); / É趨±³¾°É« g.setColor(getRandColor(200,250); g.fillRect(0, 0, width, height); /É趨×ÖÌå g.setFont(new Font("Times New Roman",Font.PLAIN,18); /»

6、73;±ß¿ò /g.setColor(new Color(); /g.drawRect(0,0,width-1,height-1); / Ëæ»ú²úÉú155Ìõ¸ÉÈÅÏߣ¬Ê¹Í¼ÏóÖеÄÈÏÖ¤Âë

7、78;»Ò×±»ÆäËü³ÌÐò̽²âµ½ 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

8、.drawLine(x,y,x+xl,y+yl); / È¡Ëæ»ú²úÉúµÄÈÏÖ¤Âë(4λÊý×Ö) String sRand="" for (int i=0;i<4;i+) String rand=String.valueOf(random.nextInt(10); sRand+=rand; / ½«

9、ÈÏÖ¤ÂëÏÔʾµ½Í¼ÏóÖÐ g.setColor(new Color(20+random.nextInt(110),20+random.nextInt(110),20+random.nextInt(110);/µ÷Óú¯Êý³öÀ´µÄÑÕ

10、1;«Ïàͬ£¬¿ÉÄÜÊÇÒòΪÖÖ×ÓÌ«½Ó½ü£¬ËùÒÔÖ»ÄÜÖ±½ÓÉú³É g.drawString(rand,13*i+6,16

11、); / ½«ÈÏÖ¤Âë´æÈëSESSION session.setAttribute("rand",sRand); / ͼÏóÉúЧ g.dispose(); ServletOutputStream responseOutputStream =response.getOutputStream(); / Êä³öÍ

12、88;Ïóµ½Ò³Ãæ ImageIO.write(image, "JPEG", responseOutputStream); /ÒÔϹرÕÊäÈëÁ÷£¡ responseOutputStream.flush(); responseOutputStream.close(); Color getRandColor(int fc,in

13、t bc)/¸ø¶¨·¶Î§»ñµÃËæ»úÑÕÉ« 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); ret

14、urn new Color(r,g,b); / <editor-fold defaultstate="collapsed" desc="HttpServlet methods. Click on the + sign on the left to edit the code."> /* Handles the HTTP <code>GET</code> method. * param request servlet request * param response servlet response */ protect

15、ed void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException processRequest(request, response); /* Handles the HTTP <code>POST</code> method. * param request servlet request * param response servlet response */ protected void doPost(HttpSer

16、vletRequest request, HttpServletResponse response) throws ServletException, IOException processRequest(request, response); /* Returns a short description of the servlet. */ public String getServletInfo() return "Short description" / </editor-fold> -ʹÓÃÑé

17、;Ö¤ÂëͼƬµÄÎļþ-index.jsp- <% page contentType="text/html;charset=gb2312" %> <!DOCTYPE HTML PUBLIC "-/W 3C/DTD HTML 4.01 Transitional/EN"> <html> <head> <title>ÈÏÖ&#

18、164;ÂëÊäÈëÒ³Ãæ</title> <meta http-equiv="Content-Type" content="text/html; charset=gb2312"> <META HTTP-EQUIV="Pragma" CONTENT="no-cache"> <META HTTP-EQUIV="Cache-Control" CONTENT=

19、"no-cache"> <META HTTP-EQUIV="Expires" CONTENT="0"> </head> <body> <form method=post action="check.jsp"> <table> <tr> <td align=left>ϵͳ²úÉúµÄÈÏÖ

20、4;Â룺</td> <td><img border=0 src=" </tr> <tr> <td align=left>ÊäÈëÉÏÃæµÄÈÏÖ¤Â룺</td> <td><input type=text name=rand maxlength=4 value=&q

21、uot;"></td> </tr> <tr> <td colspan=2 align=center><input type=submit value="Ìá½»¼ì²â"></td> </tr> </form> </body> </html> -ÑéÖ¤µÄÒ³Ãæ

22、;-check.jsp- <% page contentType="text/html; charset=gb2312" language="java" import="java.sql.*" errorPage="" %> <html> <head> <title>ÈÏÖ¤ÂëÑéÖ¤Ò³Ãæ</title> <

23、;meta http-equiv="Content-Type" content="text/html; charset=gb2312"> <META HTTP-EQUIV="Pragma" CONTENT="no-cache"> <META HTTP-EQUIV="Cache-Control" CONTENT="no-cache"> <META HTTP-EQUIV="Expires" CONTENT="0"> </head> <body> <% String rand = (String)session.getAttribute("ran