构建基于maven的综合项目(五)--验证码
一、常用注册验证码
1、servlet(需要配web.xml)或controller(需要配springMVC.xml)
package com.cpkf.notpad.controller.commonController;import java.awt.Color;import java.awt.Font;import java.awt.Graphics;import java.awt.image.BufferedImage;import java.io.IOException;import java.util.Random;import javax.imageio.ImageIO;import javax.servlet.ServletOutputStream;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import org.springframework.stereotype.Controller;import org.springframework.web.bind.annotation.RequestMapping;import org.springframework.web.bind.annotation.RequestMethod;/** * Filename: VisualCodeController.java * Description: 验证码控制器 * Company: * @author: Jiang.hu * @version: 1.0 * Create at: May 30, 2011 4:00:17 PM * modified: */@Controllerpublic class VisualCodeController {@RequestMapping(value="visualCode.do",method={RequestMethod.GET,RequestMethod.POST})public void getVisualCode(HttpServletRequest request,HttpServletResponse response){//设定图片长宽int width = 68;int height = 22;BufferedImage img = new BufferedImage(width, height, BufferedImage.TYPE_3BYTE_BGR);//得到缓冲区Graphics对象Graphics graphics = img.getGraphics();//画背景,颜色浅graphics.setColor(getRandColor(200, 250));graphics.fillRect(0, 0, width, height);//画边框graphics.setColor(getRandColor(0, 255));graphics.drawRect(0, 0, width - 1, height - 1);//随机产生两条干扰线graphics.setColor(getRandColor(160, 200));Random random = new Random();for(int i = 0;i < 2;i ++){int x = random.nextInt(width);int y = random.nextInt(height);int x1 = random.nextInt(width);int y1 = random.nextInt(height);graphics.drawLine(x, y, x1, y1);}//随机产生几个点graphics.setColor(getRandColor(160, 200));for(int i = 0;i < 10;i ++){int x = random.nextInt(width);int y = random.nextInt(height);graphics.drawLine(x, y, x, y);}//随机产生四个字符，并设置其颜色、字体、大小以及位置Font font = new Font("Times New Roman",Font.ITALIC | Font.BOLD, 22);StringBuffer sb = new StringBuffer();char[] ch = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789".toCharArray();int index,length = ch.length;for(int i = 0;i < 4;i ++){index = random.nextInt(length);graphics.setColor(getRandColor(20, 130));graphics.setFont(font);graphics.drawString("" + ch[index], (i * 15) + 3, 18);sb.append(ch[index]);}//字符串放入sessionrequest.getSession().setAttribute("checkCode", sb.toString());//生成图片graphics.dispose();//禁止图像缓存response.setHeader("Pragma", "No-cache");response.setHeader("Cache-Control", "No-cache");response.setDateHeader("Expires", 0);response.setContentType("image/jpeg");//创建二进制输出流并输出ServletOutputStream sos = null;try {sos = response.getOutputStream();ImageIO.write(img, "jpeg", sos);sos.flush();} catch (IOException e) {e.printStackTrace();} finally {if(sos != null){try {sos.close();} catch (IOException e) {e.printStackTrace();}}}}public Color getRandColor(int lower,int upper){Random random = new Random();lower = lower > 255 ? 255 : lower;lower = lower < 1 ? 1 : lower;upper = upper > 255 ? 255 : upper;upper = upper < 1 ? 1 : upper;if(lower > upper){int temp = upper;upper = lower;lower = temp;}int r = lower + random.nextInt(upper - lower);int g = lower + random.nextInt(upper - lower);int b = lower + random.nextInt(upper - lower);;return new Color(r, g, b);}}<img id="visualCode" alt="构建基于maven的综合项目(5)-验证码" src="<c:url value='/visualCode.do'/>"><a href="javascript:reloadVerifyCode();"><spring:message code="message.account.visualCode.notClear"/></a>
/* * 改变图片链接，如果自己构造url，需要在页面添加base属性，动态添加前缀 * 用下面的方式可以自动保存前缀 * */function reloadVerifyCode(){var imgSrc = $("#visualCode");var src = imgSrc.attr("src");imgSrc.attr("src",changeUrl(src));}function changeUrl(url){var timeNow = new Date().getTime();if((url.indexOf("?")) >= 0){url = url.substring(0,url.indexOf("=") + 1);url = url + timeNow;} else {url = url + "?time=" + timeNow;}return url;}