VerifyCodeUtil

  1. package cn.vision.gateway.util;
  3. import java.awt.Color;
  4. import java.awt.Font;
  5. import java.awt.Graphics;
  6. import java.awt.Graphics2D;
  7. import java.awt.RenderingHints;
  8. import java.awt.geom.AffineTransform;
  9. import java.awt.image.BufferedImage;
  10. import java.io.File;
  11. import java.io.FileOutputStream;
  12. import java.io.IOException;
  13. import java.io.OutputStream;
  14. import java.math.BigDecimal;
  15. import java.security.SecureRandom;
  16. import java.util.Arrays;
  17. import java.util.Random;
  19. import javax.imageio.ImageIO;
  21. public class VerifyCodeUtil{  
  23.     //使用到Algerian字体，系统里没有的话需要安装字体，字体只显示大写，去掉了1,0,i,o几个容易混淆的字符  
  24.     public static final String VERIFY_CODES = "23456789ABCDEFGHJKLMNPQRSTUVWXYZ";  
  25.     private static Random random = new SecureRandom();  
  28.     /** 
  29.      * 使用系统默认字符源生成验证码 
  30.      * @param verifySize    验证码长度 
  31.      * @return 
  32.      */  
  33.     public static String generateVerifyCode(int verifySize){  
  34.         return generateVerifyCode(verifySize, VERIFY_CODES);  
  35.     }  
  36.     /** 
  37.      * 使用指定源生成验证码 
  38.      * @param verifySize    验证码长度 
  39.      * @param sources   验证码字符源 
  40.      * @return 
  41.      */  
  42.     public static String generateVerifyCode(int verifySize, String sources){  
  43.         if(sources == null || sources.length() == 0){  
  44.             sources = VERIFY_CODES;  
  45.         }  
  46.         int codesLen = sources.length();  
  47.         Random rand = new SecureRandom();  
  48.         StringBuilder verifyCode = new StringBuilder(verifySize);  
  49.         for(int i = 0; i < verifySize; i++){  
  50.             verifyCode.append(sources.charAt(rand.nextInt(codesLen-1)));  
  51.         }  
  52.         return verifyCode.toString();  
  53.     }  
  55.     /** 
  56.      * 生成随机验证码文件,并返回验证码值 
  57.      * @param w 
  58.      * @param h 
  59.      * @param outputFile 
  60.      * @param verifySize 
  61.      * @return 
  62.      * @throws IOException 
  63.      */  
  64.     public static String outputVerifyImage(int w, int h, File outputFile, int verifySize) throws IOException{  
  65.         String verifyCode = generateVerifyCode(verifySize);  
  66.         outputImage(w, h, outputFile, verifyCode);  
  67.         return verifyCode;  
  68.     }  
  70.     /** 
  71.      * 输出随机验证码图片流,并返回验证码值 
  72.      * @param w 
  73.      * @param h 
  74.      * @param os 
  75.      * @param verifySize 
  76.      * @return 
  77.      * @throws IOException 
  78.      */  
  79.     public static String outputVerifyImage(int w, int h, OutputStream os, int verifySize) throws IOException{  
  80.         String verifyCode = generateVerifyCode(verifySize);  
  81.         outputImage(w, h, os, verifyCode);  
  82.         return verifyCode;  
  83.     }  
  85.     /** 
  86.      * 生成指定验证码图像文件 
  87.      * @param w 
  88.      * @param h 
  89.      * @param outputFile 
  90.      * @param code 
  91.      * @throws IOException 
  92.      */  
  93.     public static void outputImage(int w, int h, File outputFile, String code) throws IOException{  
  94.         if(outputFile == null){  
  95.             return;  
  96.         }  
  97.         File dir = outputFile.getParentFile();  
  98.         if(!dir.exists()){  
  99.             dir.mkdirs();  
  100.         }  
  101.         try{  
  102.             boolean flag = outputFile.createNewFile();  
  103.             if (!flag) {
  104.                 throw new RuntimeException("生成验证码文件错误");
  105.             }
  106.             FileOutputStream fos = new FileOutputStream(outputFile);  
  107.             outputImage(w, h, fos, code);  
  108.             fos.close();  
  109.         } catch(IOException e){  
  110.             throw e;  
  111.         }  
  112.     }  
  114.     /** 
  115.      * 输出指定验证码图片流 
  116.      * @param w 
  117.      * @param h 
  118.      * @param os 
  119.      * @param code 
  120.      * @throws IOException 
  121.      */  
  122.     public static void outputImage(int w, int h, OutputStream os, String code) throws IOException{  
  123.         int verifySize = code.length();  
  124.         BufferedImage image = new BufferedImage(w, h, BufferedImage.TYPE_INT_RGB);  
  125.         Random rand = new SecureRandom();  
  126.         Graphics2D g2 = image.createGraphics();  
  127.         g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,RenderingHints.VALUE_ANTIALIAS_ON);  
  128.         Color[] colors = new Color[5];  
  129.         Color[] colorSpaces = new Color[] { Color.WHITE, Color.CYAN,  
  130.                 Color.GRAY, Color.LIGHT_GRAY, Color.MAGENTA, Color.ORANGE,  
  131.                 Color.PINK, Color.YELLOW };  
  132.         float[] fractions = new float[colors.length];  
  133.         for(int i = 0; i < colors.length; i++){  
  134.             colors[i] = colorSpaces[rand.nextInt(colorSpaces.length)];  
  135.             fractions[i] = rand.nextFloat();  
  136.         }  
  137.         Arrays.sort(fractions);  
  139.         //g2.setColor(Color.GRAY);// 设置边框色  
  140.         g2.fillRect(0, 0, w, h);  
  142.         Color c = getRandColor(200, 250);  
  143.         g2.setColor(c);// 设置背景色  
  144.         g2.fillRect(0, 2, w, h-4);  
  146.         //绘制干扰线  
  147.         Random random = new SecureRandom();  
  148.         g2.setColor(getRandColor(160, 200));// 设置线条的颜色  
  149.         for (int i = 0; i < 20; i++) {  
  150.             int x = random.nextInt(w - 1);  
  151.             int y = random.nextInt(h - 1);  
  152.             int xl = random.nextInt(6) + 1;  
  153.             int yl = random.nextInt(12) + 1;  
  154.             //g2.drawLine(x, y, x + xl + 40, y + yl + 20);  
  155.         }  
  157.         // 添加噪点  
  158.         float yawpRate = 0.05f;// 噪声率  
  159.         BigDecimal areaTotal = BigDecimal.valueOf(yawpRate).multiply(BigDecimal.valueOf(w)).multiply(BigDecimal.valueOf(h));
  160.         int area = areaTotal.intValue();  
  161.         for (int i = 0; i < area; i++) {  
  162.             int x = random.nextInt(w);  
  163.             int y = random.nextInt(h);  
  164.             int rgb = getRandomIntColor();  
  165.             image.setRGB(x, y, rgb);  
  166.         }  
  168.         shear(g2, w, h, c);// 使图片扭曲  
  170.         g2.setColor(getRandColor(100, 160));  
  171.         int fontSize = h-4;  
  172.         Font font = new Font("Algerian", Font.ITALIC, fontSize);  
  173.         g2.setFont(font);  
  174.         char[] chars = code.toCharArray();  
  175.         for(int i = 0; i < verifySize; i++){  
  176.             AffineTransform affine = new AffineTransform();  
  177.             affine.setToRotation(Math.PI / 4 * rand.nextDouble() * (rand.nextBoolean() ? 1D : -1D), Double.parseDouble(String.valueOf((w / verifySize))) * i + fontSize/2D, h/2D);  
  178.             //g2.setTransform(affine);  
  179.             g2.drawChars(chars, i, 1, ((w-10) / verifySize) * i + 5, h/2 + fontSize/2 - 10);  
  180.         }  
  182.         g2.dispose();  
  183.         ImageIO.write(image, "jpg", os);  
  184.     }  
  186.     private static Color getRandColor(int fc, int bc) {  
  187.         if (fc > 255)  
  188.             fc = 255;  
  189.         if (bc > 255)  
  190.             bc = 255;  
  191.         int r = fc + random.nextInt(bc - fc);  
  192.         int g = fc + random.nextInt(bc - fc);  
  193.         int b = fc + random.nextInt(bc - fc);  
  194.         return new Color(r, g, b);  
  195.     }  
  197.     private static int getRandomIntColor() {  
  198.         int[] rgb = getRandomRgb();  
  199.         int color = 0;  
  200.         for (int c : rgb) {  
  201.             color = color << 8;  
  202.             color = color | c;  
  203.         }  
  204.         return color;  
  205.     }  
  207.     private static int[] getRandomRgb() {  
  208.         int[] rgb = new int[3];  
  209.         for (int i = 0; i < 3; i++) {  
  210.             rgb[i] = random.nextInt(255);  
  211.         }  
  212.         return rgb;  
  213.     }  
  215.     private static void shear(Graphics g, int w1, int h1, Color color) {  
  216.         shearX(g, w1, h1, color);  
  217.         shearY(g, w1, h1, color);  
  218.     }  
  220.     private static void shearX(Graphics g, int w1, int h1, Color color) {  
  222.         int period = random.nextInt(2);  
  224.         boolean borderGap = true;  
  225.         int frames = 1;  
  226.         int phase = random.nextInt(2);  
  228.         for (int i = 0; i < h1; i++) {  
  229.             double d = (double) (period >> 1)  
  230.                     * Math.sin((double) i / (double) period  
  231.                             + (6.2831853071795862D * (double) phase)  
  232.                             / (double) frames);  
  233.             g.copyArea(0, i, w1, 1, (int) d, 0);  
  234.             if (borderGap) {  
  235.                 g.setColor(color);  
  236.                 g.drawLine((int) d, i, 0, i);  
  237.                 g.drawLine((int) d + w1, i, w1, i);  
  238.             }  
  239.         }  
  241.     }  
  243.     private static void shearY(Graphics g, int w1, int h1, Color color) {  
  245.         int period = random.nextInt(40) + 10; // 50;  
  247.         boolean borderGap = true;  
  248.         int frames = 20;  
  249.         int phase = 7;  
  250.         for (int i = 0; i < w1; i++) {  
  251.             double d = (double) (period >> 1)  
  252.                     * Math.sin((double) i / (double) period  
  253.                             + (6.2831853071795862D * (double) phase)  
  254.                             / (double) frames);  
  255.             g.copyArea(i, 0, 1, h1, 0, (int) d);  
  256.             if (borderGap) {  
  257.                 g.setColor(color);  
  258.                 g.drawLine(i, (int) d, i, 0);  
  259.                 g.drawLine(i, (int) d + h1, i, h1);  
  260.             }  
  262.         }  
  264.     }  
  265. }

关键方法

  1. outputImage()
  2. generateVerifyCode(int verifySize, String sources)

关键点

  • 使用awt生成图片字节
  • IO流传输

不熟悉的Jar

  • javax.imageio.ImageIO 图片IO
  • java.security.SecureRandom JAVA 1.8 SecureRandom