驗證碼的實驗

1、public class VerifyCode private String sRand = ; protected String sNode =AaBbCcDdEeFfGgHhIiJjKkLlMmNnOoPpQqRrSsTtUuVvWwXxYyZz; protected String sFonts = new StringTimes New Roman,Comic Sans MS,華文行楷, MS Mincho,Gungsuh,Sylfaen,Arial, Franklin Gothic Medium,Century; public Color getRandColor(int fc, in

2、t bc) / 給定范圍獲得隨機顏色 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); public BufferedImage creatImage() / 在內存中創(chuàng)建圖象 int width = 80, heigh

3、t = 20; BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB); / 獲取圖形上下文 /Graphics g = image.getGraphics(); Graphics2D g = image.createGraphics(); AffineTransform tx =new AffineTransform(); /調整字體變形,可以產生效果,但不理想 /tx.scale(1.2, 0.9); g.transform(tx); / 生成隨機類 Random random =

4、 new Random(); / 設定背景色 g.setColor(getRandColor(200, 250); g.fillRect(0, 0, width, height); / 設定字體 g.setFont(new Font(this.getCurrentFonts(), Font.PLAIN, 18); / 畫邊框 / g.setColor(new Color(); / g.drawRect(0,0,width-1,height-1); / 隨機產生155條干擾線，使圖象中的認證碼不易被其它程序探測到 g.setColor(getRandColor(160, 200); for (i

5、nt 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); / 取隨機產生的認證碼(4位數字) for (int i = 0; i =50) ii=50; else rand = String.valueOf(random.nextInt(10); sRand += rand; / 將認證碼顯示到圖象中 g

6、.setColor(new Color(20 + random.nextInt(110), 20 + random .nextInt(110), 20 + random.nextInt(110); /調用函數出來的顏色相同，可能是因為種子太接近，所以只能直接生成 g.drawString(rand, 13 * i + 6, 16); / 圖象生效 g.dispose(); return image; public String getSRand() return sRand; public void setSRand(String rand) sRand = rand; /* * 隨機產生是數

7、字還是字符 */ public boolean getRandomBoolResult() int i =(int) (Math.round(Math.random() * 4) ); if(i%2=0) return true; return false; 二使用方法public class VerifyCodeAction extends Action Override public ActionForward execute(ActionMapping mapping, ActionForm form, HttpServletRequest request, HttpServletRes

8、ponse response) throws Excep tion VerifyCode verify = new VerifyCode(); /獲得一個實例 response.setHeader(Pragma, No-cache); /設置頭屬性 response.setHeader(Cache-Control, no-cache); response.setDateHeader(Expires, 0); BufferedImage buffImage = verify.creatImage(); /得到驗證碼圖片 HttpSession session = request.getSession(true); session.setAttribute