javaweb项目登录注册界面验证码动态生成展示

港控/mmm° 2022-06-06 13:42 218阅读 0赞

前端html代码如下

对应后端controller接口如下

/** * 获取验证码 * @param session * @param response */ @RequestMapping("validateCode")
        public void validateCode(HttpSession session, HttpServletRequest request, HttpServletResponse response){
            try {
                response.reset();
                // 设置响应的类型格式为图片格式
                response.setContentType("image/jpeg");
                //禁止图像缓存。
                response.setHeader("Pragma", "no-cache");
                response.setHeader("Cache-Control", "no-cache");
                response.setDateHeader("Expires", 0);
                String code = VerifyCodeUtils.generateVerifyCode(4);
                session.setMaxInactiveInterval(60*60*3);
                session.setAttribute("code", code);
                VerifyCodeUtils.outputImage(200,80,response.getOutputStream(),code);
                response.flushBuffer();
            } catch (Exception e) {
                logger.error("出现异常! 操作失败! 异常信息: " + e.getMessage());
            }
        }

使用utils如下

package com.ig.common.util;
    
    import java.awt.Color;
    import java.awt.Font;
    import java.awt.Graphics;
    import java.awt.Graphics2D;
    import java.awt.RenderingHints;
    import java.awt.geom.AffineTransform;
    import java.awt.image.BufferedImage;
    import java.io.File;
    import java.io.FileOutputStream;
    import java.io.IOException;
    import java.io.OutputStream;
    import java.util.Arrays;
    import java.util.Random;
    
    import javax.imageio.ImageIO;
    
    public class VerifyCodeUtils{
    
       //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
       public static final String VERIFY_CODES = "23456789";
       private static Random random = new Random();
    
    
       /** * 使用系统默认字符源生成验证码 * @param verifySize 验证码长度 * @return */ public static String generateVerifyCode(int verifySize){
          return generateVerifyCode(verifySize, VERIFY_CODES);
       }
       /** * 使用指定源生成验证码 * @param verifySize 验证码长度 * @param sources 验证码字符源 * @return */ public static String generateVerifyCode(int verifySize, String sources){
          if(sources == null || sources.length() == 0){
             sources = VERIFY_CODES;
          }
          int codesLen = sources.length();
          Random rand = new Random(System.currentTimeMillis());
          StringBuilder verifyCode = new StringBuilder(verifySize);
          for(int i = 0; i < verifySize; i++){
             verifyCode.append(sources.charAt(rand.nextInt(codesLen-1)));
          }
          return verifyCode.toString();
       }
    
       /** * 生成随机验证码文件,并返回验证码值 * @param w * @param h * @param outputFile * @param verifySize * @return * @throws IOException */ public static String outputVerifyImage(int w, int h, File outputFile, int verifySize) throws IOException{
          String verifyCode = generateVerifyCode(verifySize);
          outputImage(w, h, outputFile, verifyCode);
          return verifyCode;
       }
    
       /** * 输出随机验证码图片流,并返回验证码值 * @param w * @param h * @param os * @param verifySize * @return * @throws IOException */ public static String outputVerifyImage(int w, int h, OutputStream os, int verifySize) throws IOException{
          String verifyCode = generateVerifyCode(verifySize);
          outputImage(w, h, os, verifyCode);
          return verifyCode;
       }
    
       /** * 生成指定验证码图像文件 * @param w * @param h * @param outputFile * @param code * @throws IOException */ public static void outputImage(int w, int h, File outputFile, String code) throws IOException{
          if(outputFile == null){
             return;
          }
          File dir = outputFile.getParentFile();
          if(!dir.exists()){
             dir.mkdirs();
          }
          try{
             outputFile.createNewFile();
             FileOutputStream fos = new FileOutputStream(outputFile);
             outputImage(w, h, fos, code);
             fos.close();
          } catch(IOException e){
             throw e;
          }
       }
    
       /** * 输出指定验证码图片流 * @param w * @param h * @param os * @param code * @throws IOException */ public static void outputImage(int w, int h, OutputStream os, String code) throws IOException{
          int verifySize = code.length();
          BufferedImage image = new BufferedImage(w, h, BufferedImage.TYPE_INT_RGB);
          Random rand = new Random();
          Graphics2D g2 = image.createGraphics();
          g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,RenderingHints.VALUE_ANTIALIAS_ON);
          Color[] colors = new Color[5];
          Color[] colorSpaces = new Color[] { Color.WHITE, Color.CYAN,
                Color.GRAY, Color.LIGHT_GRAY, Color.MAGENTA, Color.ORANGE,
                Color.PINK, Color.YELLOW };
          float[] fractions = new float[colors.length];
          for(int i = 0; i < colors.length; i++){
             colors[i] = colorSpaces[rand.nextInt(colorSpaces.length)];
             fractions[i] = rand.nextFloat();
          }
          Arrays.sort(fractions);
    
          g2.setColor(Color.GRAY);// 设置边框色
          g2.fillRect(0, 0, w, h);
    
          Color c = getRandColor(200, 250);
          g2.setColor(c);// 设置背景色
          g2.fillRect(0, 2, w, h-4);
    
          //绘制干扰线
          Random random = new Random();
          g2.setColor(getRandColor(160, 200));// 设置线条的颜色
          for (int i = 0; i < 20; i++) {
             int x = random.nextInt(w - 1);
             int y = random.nextInt(h - 1);
             int xl = random.nextInt(6) + 1;
             int yl = random.nextInt(12) + 1;
             g2.drawLine(x, y, x + xl + 40, y + yl + 20);
          }
    
          // 添加噪点
          float yawpRate = 0.05f;// 噪声率
          int area = (int) (yawpRate * w * h);
          for (int i = 0; i < area; i++) {
             int x = random.nextInt(w);
             int y = random.nextInt(h);
             int rgb = getRandomIntColor();
             image.setRGB(x, y, rgb);
          }
    
          shear(g2, w, h, c);// 使图片扭曲
    
          g2.setColor(getRandColor(100, 160));
          int fontSize = h-4;
          Font font = new Font("Algerian", Font.ITALIC, fontSize);
          g2.setFont(font);
          char[] chars = code.toCharArray();
          for(int i = 0; i < verifySize; i++){
             AffineTransform affine = new AffineTransform();
             affine.setToRotation(Math.PI / 4 * rand.nextDouble() * (rand.nextBoolean() ? 1 : -1), (w / verifySize) * i + fontSize/2, h/2);
             g2.setTransform(affine);
             g2.drawChars(chars, i, 1, ((w-10) / verifySize) * i + 5, h/2 + fontSize/2 - 10);
          }
    
          g2.dispose();
          ImageIO.write(image, "jpg", os);
          //注意看以下几句的使用
          os.flush();
          os.close();
          os=null;
       }
    
       private static Color getRandColor(int fc, int bc) {
          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);
       }
    
       private static int getRandomIntColor() {
          int[] rgb = getRandomRgb();
          int color = 0;
          for (int c : rgb) {
             color = color << 8;
             color = color | c;
          }
          return color;
       }
    
       private static int[] getRandomRgb() {
          int[] rgb = new int[3];
          for (int i = 0; i < 3; i++) {
             rgb[i] = random.nextInt(255);
          }
          return rgb;
       }
    
       private static void shear(Graphics g, int w1, int h1, Color color) {
          shearX(g, w1, h1, color);
          shearY(g, w1, h1, color);
       }
    
       private static void shearX(Graphics g, int w1, int h1, Color color) {
    
          int period = random.nextInt(2);
    
          boolean borderGap = true;
          int frames = 1;
          int phase = random.nextInt(2);
    
          for (int i = 0; i < h1; i++) {
             double d = (double) (period >> 1)
                   * Math.sin((double) i / (double) period
                   + (6.2831853071795862D * (double) phase)
                   / (double) frames);
             g.copyArea(0, i, w1, 1, (int) d, 0);
             if (borderGap) {
                g.setColor(color);
                g.drawLine((int) d, i, 0, i);
                g.drawLine((int) d + w1, i, w1, i);
             }
          }
    
       }
    
       private static void shearY(Graphics g, int w1, int h1, Color color) {
    
          int period = random.nextInt(40) + 10; // 50;
    
          boolean borderGap = true;
          int frames = 20;
          int phase = 7;
          for (int i = 0; i < w1; i++) {
             double d = (double) (period >> 1)
                   * Math.sin((double) i / (double) period
                   + (6.2831853071795862D * (double) phase)
                   / (double) frames);
             g.copyArea(i, 0, 1, h1, 0, (int) d);
             if (borderGap) {
                g.setColor(color);
                g.drawLine(i, (int) d, i, 0);
                g.drawLine(i, (int) d + h1, i, h1);
             }
    
          }
    
       }