生成驗證碼效果

1 package cn.dsna.util.images; 2 3 import java.awt.Color; 4 import java.awt.Font; 5 import java.awt.Graphics2D; 6 import java.awt.image.BufferedImage; 7 import java.io.FileOutputStream; 8 import java.io.IOException; 9 import java.io.OutputStream; 10 import java.util.Random; 11 12 import javax.imageio.ImageIO; 13 /** 14 * 驗證碼生成器 15 * @author dsna 16 * 17 */ 18 public class ValidateCode { 19 // 圖片的寬度。 20 private int width = 160; 21 // 圖片的高度。 22 private int height = 40; 23 // 驗證碼字符個數 24 private int codeCount = 5; 25 // 驗證碼干擾線數 26 private int lineCount = 150; 27 // 驗證碼 28 private String code = null; 29 // 驗證碼圖片Buffer 30 private BufferedImage buffImg=null; 31 32 private char[] codeSequence = { 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 33 'K', 'L', 'M', 'N', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 34 'X', 'Y', 'Z', '1', '2', '3', '4', '5', '6', '7', '8', '9' }; 35 36 public ValidateCode() { 37 this.createCode(); 38 } 39 40 /** 41 * 42 * @param width 圖片寬 43 * @param height 圖片高 44 */ 45 public ValidateCode(int width,int height) { 46 this.width=width; 47 this.height=height; 48 this.createCode(); 49 } 50 /** 51 * 52 * @param width 圖片寬 53 * @param height 圖片高 54 * @param codeCount 字符個數 55 * @param lineCount 干擾線條數 56 */ 57 public ValidateCode(int width,int height,int codeCount,int lineCount) { 58 this.width=width; 59 this.height=height; 60 this.codeCount=codeCount; 61 this.lineCount=lineCount; 62 this.createCode(); 63 } 64 65 public void createCode() { 66 int x = 0,fontHeight=0,codeY=0; 67 int red = 0, green = 0, blue = 0; 68 69 x = width / (codeCount +2);//每個字符的寬度 70 fontHeight = height - 2;//字體的高度 71 codeY = height - 4; 72 73 // 圖像buffer 74 buffImg = new BufferedImage(width, height,BufferedImage.TYPE_INT_RGB); 75 Graphics2D g = buffImg.createGraphics(); 76 // 生成隨機數 77 Random random = new Random(); 78 // 將圖像填充為白色 79 g.setColor(Color.WHITE); 80 g.fillRect(0, 0, width, height); 81 // 創建字體 82 ImgFontByte imgFont=new ImgFontByte(); 83 Font font =imgFont.getFont(fontHeight); 84 g.setFont(font); 85 86 for (int i = 0; i < lineCount; i++) { 87 int xs = random.nextInt(width); 88 int ys = random.nextInt(height); 89 int xe = xs+random.nextInt(width/8); 90 int ye = ys+random.nextInt(height/8); 91 red = random.nextInt(255); 92 green = random.nextInt(255); 93 blue = random.nextInt(255); 94 g.setColor(new Color(red, green, blue)); 95 g.drawLine(xs, ys, xe, ye); 96 } 97 98 // randomCode記錄隨機產生的驗證碼 99 StringBuffer randomCode = new StringBuffer(); 100 // 隨機產生codeCount個字符的驗證碼。 101 for (int i = 0; i < codeCount; i++) { 102 String strRand = String.valueOf(codeSequence[random.nextInt(codeSequence.length)]); 103 // 產生隨機的顏色值,讓輸出的每個字符的顏色值都將不同。 104 red = random.nextInt(255); 105 green = random.nextInt(255); 106 blue = random.nextInt(255); 107 g.setColor(new Color(red, green, blue)); 108 g.drawString(strRand, (i + 1) * x, codeY); 109 // 將產生的四個隨機數組合在一起。 110 randomCode.append(strRand); 111 } 112 // 將四位數字的驗證碼保存到Session中。 113 code=randomCode.toString(); 114 } 115 116 public void write(String path) throws IOException { 117 OutputStream sos = new FileOutputStream(path); 118 this.write(sos); 119 } 120 121 public void write(OutputStream sos) throws IOException { 122 ImageIO.write(buffImg, "png", sos); 123 sos.close(); 124 } 125 public BufferedImage getBuffImg() { 126 return buffImg; 127 } 128 129 public String getCode() { 130 return code; 131 } 132 }

1 package cn.dsna.util.images; 2 import java.io.ByteArrayInputStream; 3 import java.awt.*; 4 /** 5 * ttf字體文件 6 * @author dsna 7 * 8 */ 9 public class ImgFontByte { 10 public Font getFont(int fontHeight){ 11 try { 12 Font baseFont = Font.createFont(Font.TRUETYPE_FONT, new ByteArrayInputStream(hex2byte(getFontByteStr()))); 13 return baseFont.deriveFont(Font.PLAIN, fontHeight); 14 } catch (Exception e) { 15 return new Font("Arial",Font.PLAIN, fontHeight); 16 } 17 } 18 19 private byte[] hex2byte(String str) { 20 if (str == null) 21 return null; 22 str = str.trim(); 23 int len = str.length(); 24 if (len == 0 || len % 2 == 1) 25 return null; 26 27 byte[] b = new byte[len / 2]; 28 try { 29 for (int i = 0; i < str.length(); i += 2) { 30 b[i / 2] = (byte) Integer 31 .decode("0x" + str.substring(i, i + 2)).intValue(); 32 } 33 return b; 34 } catch (Exception e) { 35 return null; 36 } 37 } /** 38 * ttf字體文件的十六進制字符串 39 * @return 40 */ 41 private String getFontByteStr(){ return null; 42 return str;//字符串太長 在附件中找 43 } 44 }

1 package cn.dsna.util.images; 2 3 import java.io.IOException; 4 import javax.servlet.ServletException; 5 import javax.servlet.http.HttpServlet; 6 import javax.servlet.http.HttpServletRequest; 7 import javax.servlet.http.HttpServletResponse; 8 import javax.servlet.http.HttpSession; 9 10 public class ValidateCodeServlet extends HttpServlet { 11 private static final long serialVersionUID = 1L; 12 13 @Override 14 protected void doGet(HttpServletRequest reqeust, 15 HttpServletResponse response) throws ServletException, IOException { 16 // 設置響應的類型格式為圖片格式 17 response.setContentType("image/jpeg"); 18 //禁止圖像緩存。 19 response.setHeader("Pragma", "no-cache"); 20 response.setHeader("Cache-Control", "no-cache"); 21 response.setDateHeader("Expires", 0); 22 23 HttpSession session = reqeust.getSession(); 24 25 ValidateCode vCode = new ValidateCode(120,40,5,100); 26 session.setAttribute("code", vCode.getCode()); 27 vCode.write(response.getOutputStream()); 28 } 29 /** 30 * web.xml 添加servlet 31 <servlet> 32 <servlet-name>validateCodeServlet</servlet-name> 33 <servlet-class>cn.dsna.util.images.ValidateCodeServlet</servlet-class> 34 </servlet> 35 <servlet-mapping> 36 <servlet-name>validateCodeServlet</servlet-name> 37 <url-pattern>*.images</url-pattern> 38 </servlet-mapping> 39 40 在地址欄輸入XXX/dsna.images 測試 41 */ 42 43 }

1 package cn.dsna.util.images; 2 3 import java.io.IOException; 4 import java.util.Date; 5 6 public class ValidateCodeTest { 7 8 /** 9 * @param args 10 */ 11 public static void main(String[] args) { 12 ValidateCode vCode = new ValidateCode(120,40,5,100); 13 try { 14 String path="D:/t/"+new Date().getTime()+".png"; 15 System.out.println(vCode.getCode()+" >"+path); 16 vCode.write(path); 17 } catch (IOException e) { 18 e.printStackTrace(); 19 } 20 } 21 22 }

1 <servlet> 2 <servlet-name>validateCodeServlet</servlet-name> 3 <servlet-class>cn.dsna.util.images.ValidateCodeServlet</servlet-class> 4 </servlet> 5 <servlet-mapping> 6 <servlet-name>validateCodeServlet</servlet-name> 7 <url-pattern>*.images</url-pattern> 8 </servlet-mapping>
dsnaValidateCode.jar (30.4 KB)
dsnaValidateCode_src.rar (27.5 KB)
來源網站:http://dsna.iteye.com/blog/573456