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Posted on 2011-04-16 13:49 IceWee 阅读(305) 评论(0) 编辑 收藏 所属分类: Java
仿照腾讯的Token写的验证码生成程序 Java类代码:
package icewee.image; import java.awt.BasicStroke; import java.awt.Color; import java.awt.Font; import java.awt.Graphics2D; import java.awt.RenderingHints; import java.awt.geom.Line2D; import java.awt.image.BufferedImage; import java.util.Random;
public class TokenUtil { private static final String base = "23456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefhijklmnpqrstuvwxyz"; private static final int length = base.length(); public static BufferedImage createTokenImage(int width, int height, String randomCode) { BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB); Graphics2D g = image.createGraphics(); Random random = new Random(); g.setColor(new Color(230, 230, 250)); // 设置背景色 g.fillRect(0, 0, width, height); // 填充背景 g.setColor(Color.BLACK); // 绘制边缘 g.drawRect(-1, -1, width + 1, height + 1); g.setColor(Color.GRAY); // 设置字体,随机选择字体,暂设置8种字体 Font font = new Font((new String[] { "Arial", "Arial Black", "Arial Italic", "Courier New", "Courier New Bold Italic", "Courier New Italic", "Franklin Gothic Medium", "Franklin Gothic Medium Italic" })[random.nextInt(8)], Font.PLAIN, 30); // g.setStroke(new BasicStroke((float)(Math.random()), BasicStroke.CAP_BUTT, BasicStroke.JOIN_BEVEL)); g.setFont(font); // 定义字体颜色范围 int red = random.nextInt(160), green = random.nextInt(50), blue = random.nextInt(50); // 定义一个无干扰线区间和一个起始位置 int nor = random.nextInt(50), rsta = random.nextInt(131); // 绘制干扰正弦曲线 M:曲线平折度, D:Y轴常量 V:X轴焦距 int M = random.nextInt(15) + 5, D = random.nextInt(23) + 15, V = random.nextInt(5) + 1; double x = 0.0; double y = M * Math.sin(Math.toRadians(V * x)) + D; double px, py; for (int i = 0; i < 131; i++) { px = x + 1; py = M * Math.sin(Math.toRadians(V * px)) + D; if (rsta < i && i < (rsta + nor)) g.setColor(new Color(230, 230, 250)); else g.setColor(new Color(red, green, blue)); // 随机设置像素点宽带(线宽) g.setStroke(new BasicStroke((float) (Math.random() + 1.5f))); g.draw(new Line2D.Double(x, y, px, py)); x = px; y = py; } char[] codes = randomCode.toCharArray(); for (int i = 0; i < codes.length; i++) { // 旋转图形 int degree = (random.nextInt(20) - 10) % 360; double ang = degree * 0.0174532925; // 将角度转为弧度 g.rotate(ang, width / 2, height / 2); g.setColor(new Color(red, green, blue)); g.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON); int gr = random.nextInt(8); g.drawString(String.valueOf(codes[i]), 24 * i + 10 + gr, 38); } g.dispose(); return image; } public static String createRandomCode(int size, int width, int height) { StringBuffer randomCode = new StringBuffer(); for (int i = 0; i < size; i++) { Random random = new Random(); int start = random.nextInt(length); String strRand = base.substring(start, start + 1); randomCode.append(strRand); } return randomCode.toString(); } }
JSP页面:
<%@page contentType="image/jpeg" pageEncoding="GBK"%> <%@page import="java.awt.image.BufferedImage"%> <%@page import="javax.imageio.ImageIO"%> <%@page import="com.icesoft.image.TokenUtil"%>
<% //设置页面不缓存 response.setHeader("Pragma", "No-cache"); response.setHeader("Cache-Control", "no-cache"); response.setDateHeader("Expires", 0); int width = 120, height = 50; String randomCode = TokenUtil.createRandomCode(4, width, height); System.out.println("生成的随机码:" + randomCode); BufferedImage image = TokenUtil.createTokenImage(width, height, randomCode); ImageIO.write(image, "JPEG", response.getOutputStream()); response.flushBuffer(); out.clear(); out = pageContext.pushBody(); %>
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