kaptcha验证码

String kaptchaExpected = (String)ActionContext.getContext().getSession().get(com.google.code.kaptcha.Constants.KAPTCHA_SESSION_KEY);

6.点击图片更换验证码

7.SpringMVC中的使用

//java@Controller@RequestMapping("/Captcha")public class CaptchaRandomCodeController {	private Producer captchaProducer = null;	@Autowired	public void setCaptchaProducer(Producer captchaProducer) {		this.captchaProducer = captchaProducer;	}	@RequestMapping("/captcha-image")	public ModelAndView handleRequest(HttpServletRequest request, HttpServletResponse response) throws Exception {		response.setDateHeader("Expires", 0);// 禁止server端缓存		// 设置标准的 HTTP/1.1 no-cache headers.		response.setHeader("Cache-Control", "no-store, no-cache, must-revalidate");		// 设置IE扩展 HTTP/1.1 no-cache headers (use addHeader).		response.addHeader("Cache-Control", "post-check=0, pre-check=0");		response.setHeader("Pragma", "no-cache");// 设置标准 HTTP/1.0 不缓存图片		response.setContentType("image/jpeg");// 返回一个 jpeg 图片，默认是text/html(输出文档的MIMI类型)		String capText = captchaProducer.createText();// 为图片创建文本				// 将文本保存在session中。这里就使用包中的静态变量吧		request.getSession().setAttribute(Constants.KAPTCHA_SESSION_KEY, capText);		BufferedImage bi = captchaProducer.createImage(capText); // 创建带有文本的图片		ServletOutputStream out = response.getOutputStream();		// 图片数据输出		ImageIO.write(bi, "jpg", out);		try {			out.flush();		} finally {			out.close();		}		System.out.println("Session 验证码是：" + request.getSession().getAttribute(Constants.KAPTCHA_SESSION_KEY));		return null;	}}

      
      
      	
       		
        			
         				
          					
           
            yes
           					
           
            105,179,90
           					
           
            160
           					
           
            50
           					
           
            code
           					
           
            red
           					
           
            35
           					
           
            3
           					
           
            5
           					
           					
           
            彩云,宋体,楷体,微软雅黑
           				
          			
         		
        	
       
      

                 验证码：                    

8.验证码参数详细