在Spring中使用jcaptcha实现图片验证

转载来自http://sha0k.iteye.com/blog/1364950

在Spring中使用jcaptcha首先要添加jcaptcha的包 我使用的是jcaptcha-1.0-all.jar 官网http://jcaptcha.sourceforge.net/jcaptcha/index.html
还要添加commons-collections-*.*.jar 版本自己控制
首先是ApplicationContext.xml的配置，这里主要是对验证码生成器服务的注入，控制类就是Spring Web中的Controller，没有什么特别的
Xml代码 
<bean id="imageCaptchaService" class="com.octo.captcha.service.image.DefaultManageableImageCaptchaService">   
        <constructor-arg type="com.octo.captcha.service.captchastore.CaptchaStore" index="0">   
            <ref bean="fastHashMapCaptchaStore"/>   
        </constructor-arg>      
        <!--which captcha Engine you use-->      
        <constructor-arg type="com.octo.captcha.engine.CaptchaEngine" index="1">   
            <ref bean="captchaEngineEx"/>   
        </constructor-arg>      
        <constructor-arg index="2">      
            <value>180</value>      
        </constructor-arg>      
        <constructor-arg index="3">      
            <value>100000</value>      
        </constructor-arg>      
        <constructor-arg index="4">      
            <value>75000</value>      
        </constructor-arg>     
    </bean>   
    <bean id="fastHashMapCaptchaStore"  
        class="com.octo.captcha.service.captchastore.FastHashMapCaptchaStore"/>      
    <!--you can define more than one captcha engine here -->      
    <bean id="captchaEngineEx"  
        class="com.sha0k.util.CaptchaEngineEx"/> 
下面是验证码生成器CaptchaEngineEx，自己编写：
Java代码 
import java.awt.Color; 
import java.awt.Font; 
import java.awt.image.ImageFilter; 
 
import com.octo.captcha.component.image.backgroundgenerator.BackgroundGenerator; 
import com.octo.captcha.component.image.backgroundgenerator.UniColorBackgroundGenerator; 
import com.octo.captcha.component.image.color.RandomListColorGenerator; 
import com.octo.captcha.component.image.deformation.ImageDeformation; 
import com.octo.captcha.component.image.deformation.ImageDeformationByFilters; 
import com.octo.captcha.component.image.fontgenerator.FontGenerator; 
import com.octo.captcha.component.image.fontgenerator.RandomFontGenerator; 
import com.octo.captcha.component.image.textpaster.DecoratedRandomTextPaster; 
import com.octo.captcha.component.image.textpaster.TextPaster; 
import com.octo.captcha.component.image.textpaster.textdecorator.TextDecorator; 
import com.octo.captcha.component.image.wordtoimage.DeformedComposedWordToImage; 
import com.octo.captcha.component.image.wordtoimage.WordToImage; 
import com.octo.captcha.component.word.wordgenerator.RandomWordGenerator; 
import com.octo.captcha.component.word.wordgenerator.WordGenerator; 
import com.octo.captcha.engine.image.ListImageCaptchaEngine; 
import com.octo.captcha.image.gimpy.GimpyFactory; 
 
public class CaptchaEngineEx extends ListImageCaptchaEngine { 
 
    protected void buildInitialFactories() { 
        int minWordLength = 4; 
        int maxWordLength = 5; 
        int fontSize = 50; 
        int imageWidth = 250; 
        int imageHeight = 100; 
 
        WordGenerator wordGenerator = new RandomWordGenerator( 
                "0123456789abcdefghijklmnopqrstuvwxyz"); 
 
        TextPaster randomPaster = new DecoratedRandomTextPaster(minWordLength, 
                maxWordLength, new RandomListColorGenerator(new Color[] { 
                        new Color(23, 170, 27), new Color(220, 34, 11), 
                        new Color(23, 67, 172) }), new TextDecorator[] {}); 
        BackgroundGenerator background = new UniColorBackgroundGenerator( 
                imageWidth, imageHeight, Color.white); 
        FontGenerator font = new RandomFontGenerator(fontSize, fontSize, 
                new Font[] { new Font("nyala", Font.BOLD, fontSize), 
                        new Font("Bell MT", Font.PLAIN, fontSize), 
                        new Font("Credit valley", Font.BOLD, fontSize) }); 
 
        ImageDeformation postDef = new ImageDeformationByFilters( 
                new ImageFilter[] {}); 
        ImageDeformation backDef = new ImageDeformationByFilters( 
                new ImageFilter[] {}); 
        ImageDeformation textDef = new ImageDeformationByFilters( 
                new ImageFilter[] {}); 
 
        WordToImage word2image = new DeformedComposedWordToImage(font, 
                background, randomPaster, backDef, textDef, postDef); 
        addFactory(new GimpyFactory(wordGenerator, word2image)); 
 
    } 
 
} 
验证码图片的显示是一个向服务器请求的过程 所以必须有serlvet来处理这个请求，下面是显示验证码的控制器类
Java代码 
import java.awt.image.BufferedImage; 
import java.io.ByteArrayOutputStream; 
import java.io.IOException; 
 
import javax.annotation.Resource; 
import javax.servlet.ServletException; 
import javax.servlet.ServletOutputStream; 
import javax.servlet.http.HttpServletRequest; 
import javax.servlet.http.HttpServletResponse; 
 
import org.springframework.stereotype.Controller; 
import org.springframework.ui.Model; 
import org.springframework.web.bind.annotation.RequestMapping; 
 
import com.octo.captcha.service.CaptchaServiceException; 
import com.octo.captcha.service.image.ImageCaptchaService; 
import com.sun.image.codec.jpeg.ImageFormatException; 
import com.sun.image.codec.jpeg.JPEGCodec; 
import com.sun.image.codec.jpeg.JPEGImageEncoder; 
 
@Controller 
public class GenerateImageController{ 
 
    @Resource(name = "imageCaptchaService") 
    private ImageCaptchaService imageCaptchaService; 
 
    @RequestMapping(value = "/generatImage") 
    public void ImageCaptcha(HttpServletRequest request , HttpServletResponse response , Model model)  
     throws ServletException, IOException{ 
 
        byte[] captchaChallengeAsJpeg = null; 
        // the output stream to render the captcha image as jpeg into 
        ByteArrayOutputStream jpegOutputStream = new ByteArrayOutputStream(); 
        try { 
            // get the session id that will identify the generated captcha. 
            // the same id must be used to validate the response, the session id 
            // is a good candidate! 
            String captchaId = request.getSession().getId(); 
            // call the ImageCaptchaService getChallenge method 
            BufferedImage challenge = imageCaptchaService 
                    .getImageChallengeForID(captchaId, request 
                            .getLocale()); 
 
            // a jpeg encoder 
            JPEGImageEncoder jpegEncoder = JPEGCodec 
                    .createJPEGEncoder(jpegOutputStream); 
            jpegEncoder.encode(challenge); 
        } catch (IllegalArgumentException e) { 
        } catch (CaptchaServiceException e) { 
        } catch (ImageFormatException e) { 
            // TODO Auto-generated catch block 
            e.printStackTrace(); 
        } catch (IOException e) { 
            // TODO Auto-generated catch block 
            e.printStackTrace(); 
        } 
         
        captchaChallengeAsJpeg = jpegOutputStream.toByteArray();   
        // flush it in the response   
        response.setHeader("Cache-Control", "no-store");   
        response.setHeader("Pragma", "no-cache");   
        response.setDateHeader("Expires", 0);   
        response.setContentType("image/jpeg");   
        ServletOutputStream responseOutputStream = response   
                .getOutputStream();   
        responseOutputStream.write(captchaChallengeAsJpeg);   
        responseOutputStream.flush();   
        responseOutputStream.close(); 
    } 
 
} 
  而页面的图片显示只要这么简简单单的一句就够了 getimg.jsp页面
Html代码 
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> 
<html> 
  <head> 
    <base href="<%=basePath%>"> 
     
    <title>My JSP 'getimg.jsp' starting page</title> 
     
    <meta http-equiv="pragma" content="no-cache"> 
    <meta http-equiv="cache-control" content="no-cache"> 
    <meta http-equiv="expires" content="0">     
    <meta http-equiv="keywords" content="keyword1,keyword2,keyword3"> 
    <meta http-equiv="description" content="This is my page"> 
    <!--
    <link rel="stylesheet" type="text/css" href="styles.css">
    --> 
 
  </head> 
   
  <body> 
    <img alt="" src="generatImage"> 
  </body> 
</html> 

验证用户输入的验证码的控制类
Java代码 
import java.io.IOException; 
 
import javax.annotation.Resource; 
import javax.servlet.ServletException; 
import javax.servlet.http.HttpServletRequest; 
import javax.servlet.http.HttpServletResponse; 
 
import org.springframework.stereotype.Controller; 
import org.springframework.web.bind.annotation.RequestMapping; 
 
import com.octo.captcha.service.CaptchaServiceException; 
import com.octo.captcha.service.image.ImageCaptchaService; 
 
@Controller 
public class ImageValidationController { 
 
    @Resource(name = "imageCaptchaService") 
    ImageCaptchaService imageCaptchaService; 
     
    @RequestMapping(value = "/validateImage") 
    public void ValidateCaptchaImage(HttpServletRequest request,      
            HttpServletResponse response)throws ServletException , IOException { 
        Boolean isResponseCorrect = Boolean.FALSE;      
        //remenber that we need an id to validate!      
        String captchaId = request.getSession().getId();      
        //retrieve the response      
        String captcha_value = request.getParameter("captcha_value");      
        // Call the Service method      
        try {      
            isResponseCorrect = imageCaptchaService.validateResponseForID(captchaId, captcha_value);   
        } catch (CaptchaServiceException e) {      
            //should not happen, may be thrown if the id is not valid       
        }      
        System.out.println(isResponseCorrect);    
       // httpServletResponse.encodeUrl("sucess.html");   
        if(isResponseCorrect.booleanValue()){   
            response.sendRedirect("success.html");   
        }   
        else {   
            response.sendRedirect("failture.html");   
        }   
    }      
} 
验证页面：

Html代码 
<html> 
  <head> 
    <base href="<%=basePath%>"> 
    <script type="text/javascript" 
            src="http://ajax.googleapis.com/ajax/libs/jquery/1.4.2/jquery.min.js"></script> 
        <script type="text/javascript" 
            src="http://jquery-json.googlecode.com/files/jquery.json-2.2.min.js"></script> 
        <script type="text/javascript"> 
             
                function ajaxRefresh(){   
       
                document.getElementById("image").contentWindow.location.reload();    
                }   
         
         
        </script> 
     
    <title>My JSP 'image.jsp' starting page</title> 
     
    <meta http-equiv="pragma" content="no-cache"> 
    <meta http-equiv="cache-control" content="no-cache"> 
    <meta http-equiv="expires" content="0">     
    <meta http-equiv="keywords" content="keyword1,keyword2,keyword3"> 
    <meta http-equiv="description" content="This is my page"> 
    <!--
    <link rel="stylesheet" type="text/css" href="styles.css">
    --> 
 
  </head> 
   
  <body> 
    <iframe src="getimg.jsp" id="image"></iframe> 
    <a href="javascript:void(0)" onclick="ajaxRefresh()">ajaxRefresh</a> 
    <form action="validateImage"> 
        <input type='text' name='captcha_value'> 
        <input type="submit" value="提交"> 
    </form>  
  </body> 
</html>