验证码工具类

	package com.utils;

	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 ZJ_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 = "23456789ABCDEFGHJKLMNPQRSTUVWXYZ";
		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);
		}

		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);
				}

			}

		}

		public static void main(String[] args) throws IOException {
			File dir = new File("F:/verifies");
			int w = 200, h = 80;
			for (int i = 0; i < 50; i++) {
				String verifyCode = generateVerifyCode(4);
				File file = new File(dir, verifyCode + ".jpg");
				outputImage(w, h, file, verifyCode);
			}
		}
	}

controller中(jfinal)

	public void verifyCode() throws IOException {
		HttpServletResponse response = getResponse();
		HttpServletRequest request = getRequest();
		response.setHeader("Pragma", "No-cache");
		response.setHeader("Cache-Control", "no-cache");
		response.setDateHeader("Expires", 0);
		response.setContentType("image/jpeg");
		HttpSession session = request.getSession(true);

		// 生成随机字串
		String verifyCode = ZJ_VerifyCodeUtils.generateVerifyCode(4);
		// 存入会话session
		session.setAttribute("code", verifyCode.toLowerCase());
		// 生成图片
		int w = 200, h = 80;
		ZJ_VerifyCodeUtils.outputImage(w, h, response.getOutputStream(), verifyCode);
		renderNull();
	}

页面中

<img id="login_verifyCode" alt="" src="${basePath!}html/verifyCode" style="height: 25px;width: 58px;">

事件

$("#login_verifyCode").click(function() {
	var date = new Date();
	$("#login_verifyCode").attr("src", "${basePath!}html/verifyCode?date=" + date);
})

原文:大专栏  验证码类


02-13 13:20