Spring MVC Captcha 验证码 (附Servlet实现方式)

本文专为不想一遍遍手写验证码代码的”懒猿“而生，只需要添加部分配置文件，拷贝一个控制层代码，就能在页面中方便使用。话不多说，进入主题：

一. Spring MVC 环境实现方式：

1.1 spring-mvc.xml 

	
	
		
			
				
					
						no
						105,179,90
						red
						200
						48
						48
						code
						123456789
						4
						6
						宋体,楷体,微软雅黑
						com.google.code.kaptcha.impl.WaterRipple
					
				
			
		
	

1.2 Controller 实现

package com.vopzoon.app.base.captcha;

import java.awt.image.BufferedImage;

import javax.imageio.ImageIO;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.servlet.ModelAndView;

import com.google.code.kaptcha.Constants;
import com.google.code.kaptcha.Producer;

/**
 * 防止Captcha机器人登陆
 * @author liuwang
 *
 */
@Controller
@RequestMapping("/kaptcha/*")
public class CaptchaController {
	
	@Autowired
	private Producer captchaProducer = null;

	@RequestMapping
	public ModelAndView getKaptchaImage(HttpServletRequest request, HttpServletResponse response) throws Exception {
		HttpSession session = request.getSession();
		String code = (String)session.getAttribute(Constants.KAPTCHA_SESSION_KEY);
		System.out.println("******************验证码是: " + code + "******************");
		
		response.setDateHeader("Expires", 0);
		
		// Set standard HTTP/1.1 no-cache headers.
		response.setHeader("Cache-Control", "no-store, no-cache, must-revalidate");
		
		// Set IE extended HTTP/1.1 no-cache headers (use addHeader).
		response.addHeader("Cache-Control", "post-check=0, pre-check=0");
		
		// Set standard HTTP/1.0 no-cache header.
		response.setHeader("Pragma", "no-cache");
		
		// return a jpeg
		response.setContentType("image/jpeg");
		
		// create the text for the image
		String capText = captchaProducer.createText();
		
		// store the text in the session
		session.setAttribute(Constants.KAPTCHA_SESSION_KEY, capText);
		
		// create the image with the text
		BufferedImage bi = captchaProducer.createImage(capText);
		ServletOutputStream out = response.getOutputStream();
		
		// write the data out
		ImageIO.write(bi, "jpg", out);
		try {
			out.flush();
		} finally {
			out.close();
		}
		return null;
	}

}

3. JSP 代码

<%@ page language="java" contentType="text/html; charset=UTF-8"
	pageEncoding="UTF-8"%>











		

      验证码:
                   
      
      

      
      看不清?换一张

PS：需要自行引入kaptcha.jar；

二：servlet实现方式

2.1 web.xml 配置：

	
		
		kaptcha
		com.google.code.kaptcha.servlet.KaptchaServlet
		
			
			kaptcha.border
			yes
		
		
			
			kaptcha.border.color
			105,179,90
				
		
			
			kaptcha.textproducer.font.color
			red
		
		
			
			kaptcha.image.width
			250
		
		
			
			kaptcha.image.height
			90
		
		
			
			kaptcha.textproducer.font.size
			70
		
		
			
			kaptcha.session.key
			code
		
		
			
			kaptcha.textproducer.char.length
			4
		
		
			
			kaptcha.textproducer.font.names
			宋体,楷体,微软雅黑
				
	

    
		kaptcha
		/kaptcha/kaptcha.jpg
	

2.2 JSP代码

			

				

				

			
					

						
sec code:

						
					
				
			
		
	

		




		
		<%
			String c = (String)session.getAttribute(com.google.code.kaptcha.Constants.KAPTCHA_SESSION_KEY);
			String parm = (String) request.getParameter("kaptchafield");
			
			out.println("Parameter: " + parm + " ? Session Key: " + c + " : ");
			
			if (c != null && parm != null) {
				if (c.equals(parm)) {
					out.println("true");
				} else {
					out.println("false");
				}
			
		%>

原文链接： http://ttaale.iteye.com/blog/808719