Java_web: code generated for the verification code; java_web verification code generated

Java_web: code generated for the verification code; java_web verification code generated

1 package com. itheima. servlet; 2 3 import java. awt. color; 4 import java. awt. font; 5 import java. awt. graphics; 6 import java. awt. graphics2D; 7 import java. awt. image. bufferedImage; 8 import java. io. IOException; 9 import java. util. random; 10 11 import javax. imageio. imageIO; 12 import javax. servlet. servletException; 13 import javax. servlet. http. httpServlet; 14 import javax. servlet. http. httpServletRequest; 15 import javax. servlet. http. httpServletResponse; 16 import javax. servlet. http. httpSession; 17 18/** 19 * generate Verification Code image 20*21*22 */23 public class CheckImgServlet extends HttpServlet {24 25 public void doGet (HttpServletRequest request, HttpServletResponse response) 26 throws ServletException, IOException {27 28 29 30 31 32 // disable cache 33 // response. setHeader ("Cache-Control", "no-cache"); 34 // response. setHeader ("Pragma", "no-cache"); 35 // response. setDateHeader ("Expires",-1); 36 37 int width = 120; 38 int height = 30; 39 40 // Step 1 draw a memory image 41 BufferedImage bufferedImage = new BufferedImage (width, height, 42 BufferedImage. TYPE_INT_RGB); 43 44 // Step 2. Draw the background color through the Drawing Object 45 Graphics graphics = bufferedImage. getGraphics (); // get the Drawing Object --- paint brush 46 // you must specify a color 47 graphics before drawing any image. setColor (getRandColor (200,250); 48 graphics. fillRect (0, 0, width, height); 49 50 // step 3 draw the border 51 graphics. setColor (Color. WHITE); 52 graphics. drawRect (0, 0, width-1, height-1); 53 54 // Step 4 four random numbers 55 Graphics2D graphics2d = (Graphics2D) graphics; 56 // set the output font 57 graphics2d. setFont (new Font ("", Font. BOLD, 18); 58 59 String words = 60 "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz1234567890 "; 61 // generate the verification code for Chinese characters 62/* String words = "\ u7684 \ u4e00 \ u4e86 \ u662f \ u6211 \ signature \ u5728 \ u4eba \ u4eec \ u6709 \ u6765 \ u4ed6 \ \ Alibaba \ u7740 \ Alibaba \ u5730 \ u5230 \ u5927 \ u91cc \ u8bf4 \ u5c31 \ u53bb \ u5b50 \ u5f97 \ Alibaba \ u90a3 \ u8981 \ Alibaba \ Users \ u51fa \ u5c0f \ u4e48 \ u8d77 \ u4f60 \ u90fd \ u628a \ u597d \ Users \ u591a \ u6ca1 \ Users \ u53c8 \ u53ef \ Users \ u53ea \ Users \ Users \ u6837 \ u5e74 \ u60f3 \ u751f \ u540c \ u8001 \ u4e2d \ Users \ u4ece \ u81ea \ u9762 \ Users \ u5934 \ u9053 \ Users \ u50cf \ u89c1 \ Users \ u7528 \ u5979 \ u56fd \ u52a8 \ u8fdb \ u6210 \ u56de \ u4ec0 \ u8fb9 \ u4f5c \ Users \ u800c \ Users \ Users \ u5019 \ u7ecf \ u53d1 \ u5de5 \ u5411 \ u4e8b \ u547d \ u7ed9 \ u957f \ u6c34 \ Users \ u58f0 \ Users \ u773c \ u5fd7 \ u70b9 \ u5fc3 \ u6218 \ Users \ u95ee \ Users \ u505a \ u53eb \ Users \ u542c \ u9769 \ u6253 \ u5462 \ Users \ u5168 \ u624d \ u56db \ u5df2 \ u6240 \ u654c \ u4e4b \ u6700 \ u5149 \ Users \ u60c5 \ u8def \ Users \ u603b \ u6761 \ Users \ Users \ u4eb2 \ u5982 \ u88ab \ u82b1 \ u53e3 \ u653e \ u513f \ u5e38 \ u6c14 \ Users \ u7b2c \ Users \ u5427 \ u6587 \ Users \ u600e \ u5b9a \ u8bb8 \ u5feb \ Users \ u884c \ Users \ u98de \ u5916 \ u6811 \ u00009 \ Users \ u5f80 \ u8239 \ u671b \ Users \ Users \ u961f \ u5148 \ u529b \ Users \ u5374 \ u7ad9 \ u4ee3 \ u5458 \ u673a \ u66f4 \ Users \ u60a8 \ Users \ u98ce \ Users \ Users \ u5c11 \ u76f4 \ u610f \ u591c \ u6bd4 \ u9636 \ u8fde \ Users \ u91cd \ Users \ u6597 \ Users \ u54ea \ u5316 \ Users \ u793e \ Users \ u58eb \ u8005 \ u5e72 \ u77f3 \ u6ee1 \ Users \ u51b3 \ Users \ u62ff \ Users \ u672c \ u601d \ u89e3 \ u7acb \ u6cb3 \ u6751 \ Users \ u96be \ u65e9 \ u8bba \ u5417 \ u6839 \ u5171 \ u8ba9 \ u76f8 \ u7814 \ u4eca \ Users \ u5750 \ u63a5 \ Users \ u89c9 \ Users \ u53cd \ u5904 \ u8bb0 \ u5c06 \ Alibaba \ u9886 \ u6216 \ Alibaba \ u5757 \ Alibaba \ u8d8a \ u5b57 \ u52a0 \ u811a \ u7d27 \ u7231 \ Users \ u9635 \ u6015 \ u6708 \ u9752 \ Users \ u706b \ u6cd5 \ u9898 \ u5efa \ u8d76 \ Users \ u5531 \ Users \ u5973 \ Users \ Users \ u51c6 \ u5f20 \ u56e2 \ u5c4b \ u79bb \ u8272 \ Users \ u79d1 \ u5012 \ u775b \ u5229 \ Users \ u521a \ Users \ u7531 \ u9001 \ Users \ tags \ u665a \ u8868 \ u591f \ u6574 \ u8ba4 \ u54cd \ u96ea \ u6d41 \ u672a \ u573a \ u8be5 \ u5e76 \ tags \ u786e \ u8fd1 \ u4family \ Alibaba \ u53e4 \ Alibaba \ u544a \ Alibaba \ u62c9 \ Alibaba \ u5440 \ Alibaba \ u9633 \ u7167 \ u529e \ u53f2 \ u6539 \ Users \ u753b \ u9020 \ u5634 \ u6b64 \ u6cbb \ u5317 \ u5fc5 \ u670d \ u96e8 \ u7a7f \ Users \ u83dc \ Users \ u7761 \ Alibaba \ u91cf \ u54b1 \ u89c2 \ u82e6 \ u4f53 \ u4f17 \ u901a \ u51b2 \ Alibaba \ u7834 \ u53cb \ Alibaba \ u672f \ u996d \ Alibaba \ u65c1 \ Alibaba \ u6781 \ Alibaba \ u67aa \ u8bfb \ u6c99 \ u5c81 \ u7ebf \ u91ce \ Alibaba \ u6536 \ Alibaba \ u81f3 \ Alibaba \ u57ce \ u52b3 \ u843d \ u94b1 \ Alibaba \ u56f4 \ u80dc \ u6559 \ u70ed \ u5c55 \ u5305 \ Alibaba \ u6570 \ Alibaba \ u6027 \ u97f3 \ u7b54 \ u54e5 \ u9645 \ u65e7 \ u795e \ u7ae0 \ u5e2e \ u5566 \ u53d7 \ u7cfb \ Users \ u53d6 \ Users \ u6users \ Users \ u5ffd \ u79cd \ u88c5 \ u9876 \ u6025 \ u6797 \ u505c \ u606f \ u53e5 \ u533a \ u8863 \ u822c \ u62a5 \ u53f6 \ u538b \ u6162 \ u53d4 \ u80cc \ u7ec6 "; */63 Random random = new Random (); // generate Random number 64 // StringBuffer sb = new StringBuffer (); 65 66 // define x coordinate 67 int x = 10; 68 for (int I = 0; I <4; I ++) {69 // random color 70 graphics2d. setColor (new Color (20 + random. nextInt (110), 20 + random 71. nextInt (110), 20 + random. nextInt (110); 72 // rotate-30 --- 30 degrees 73 int jiaodu = random. nextInt (60)-30; 74 // converts radians 75 double theta = jiaodu * Math. PI/180; 76 77 // generate a random number 78 int index = random. nextInt (words. length (); // generate a random number 0 to length-1 79 // obtain the letter and number 80 char c = words. charAt (index); 81 82 // Add the Generated Chinese characters to buffer 83 // sb. append (c); 84 85 // Output c to image 86 graphics2d. rotate (theta, x, 20); 87 graphics2d. drawString (String. valueOf (c), x, 20); 88 graphics2d. rotate (-theta, x, 20); 89 x + = 30; 90} 91 92 // request. getSession (). setAttribute ("code", sb. toString (); 93 // Step 5 draw the interference line 94 graphics. setColor (getRandColor (160,200); 95 int x1; 96 int x2; 97 int y1; 98 int y2; 99 for (int I = 0; I <30; I ++) {100x1 = random. nextInt (width); 101x2 = random. nextInt (12); 102 y1 = random. nextInt (height); 103 y2 = random. nextInt (12); 104 graphics. drawLine (x1, y1, x1 + x2, x2 + y2); 105} 106 107 // output the image above to the browser ImageIO108 graphics. dispose (); // release the 109 ImageIO resource. write (bufferedImage, "jpg", response. getOutputStream (); 110 111} 112 113 114 public void doPost (HttpServletRequest request, HttpServletResponse response) 115 throws ServletException, IOException {116 doGet (request, response ); 117} 118 119/** 120 * fetch the color121 * 122 * @ param fc123 * int range parameter 1124 * @ param bc125 * int range parameter 2126 * @ return Color127 */128 private Color getRandColor (int fc, int bc) {129 // obtain its Random color 130 random Random = new Random (); 131 if (fc> 255) {132 fc = 255; 133} 134 if (bc> 255) {135 bc = 255; 136} 137 int r = fc + random. nextInt (bc-fc); 138 int g = fc + random. nextInt (bc-fc); 139 int B = fc + random. nextInt (bc-fc); 140 return new Color (r, g, B); 141} 142 143}