利用开源组件制作验证码 SimpleCaptcha 【转】

 

转载：http://blog.ntsky.com/simplecaptcha.html

使用SimpleCaptcha可以方便灵活的生成各种验证码。

下载SimpleCaptcha : http://sourceforge.net/project/platformdownload.php?group_id=147810&sel_platform=13579

添加到ClassPath中，在web.xml中的设置:

XML/HTML代码

<
servlet
>
    
<
servlet-name
>


Captcha
</
servlet-name
>
    
<
servlet-class
>


nl.captcha.servlet.CaptchaServlet
</
servlet-class
>
    
<
init-param
>
        
<
param-name
>


cap.font.color
</
param-name
>
        
<
param-value
>


0,0,255
</
param-value
>
    
</
init-param
>
    
<
init-param
>
        
<
param-name
>


cap.char.arr
</
param-name
>
        
<
param-value
>


1,2,3,4,5,6,7,8,9,0
</
param-value
>
    
</
init-param
>
    
<
init-param
>
        
<
param-name
>


cap.border
</
param-name
>
        
<
param-value
>


yes
</
param-value
>
    
</
init-param
>
    
<
init-param
>
        
<
param-name
>


cap.border.c
</
param-name
>
        
<
param-value
>


black
</
param-value
>
    
</
init-param
>
    
<
init-param
>
        
<
param-name
>


cap.border.th
</
param-name
>
        
<
param-value
>


1
</
param-value
>
    
</
init-param
>
    
<
init-param
>
        
<
param-name
>


cap.background.c.to
</
param-name
>
        
<
param-value
>


255,255,255
</
param-value
>
    
</
init-param
>
    
<
init-param
>
        
<
param-name
>


cap.background.c.from
</
param-name
>
        
<
param-value
>


255,255,255
</
param-value
>
    
</
init-param
>
</
servlet
>
<
servlet-mapping
>
    
<
servlet-name
>


Captcha
</
servlet-name
>
    
<
url-pattern
>


/servlet/Captcha.jpg
</
url-pattern
>
</
servlet-mapping
>

<servlet>  
    <servlet-name>Captcha</servlet-name>   
    <servlet-class>nl.captcha.servlet.CaptchaServlet</servlet-class>   
    <init-param>   
        <param-name>cap.font.color</param-name>   
        <param-value>0,0,255</param-value>   
    </init-param>   
    <init-param>   
        <param-name>cap.char.arr</param-name>   
        <param-value>1,2,3,4,5,6,7,8,9,0</param-value>   
    </init-param>   
    <init-param>   
        <param-name>cap.border</param-name>   
        <param-value>yes</param-value>   
    </init-param>           
    <init-param>   
        <param-name>cap.border.c</param-name>   
        <param-value>black</param-value>   
    </init-param>           
    <init-param>   
        <param-name>cap.border.th</param-name>   
        <param-value>1</param-value>   
    </init-param>       
    <init-param>   
        <param-name>cap.background.c.to</param-name>   
        <param-value>255,255,255</param-value>   
    </init-param>   
    <init-param>   
        <param-name>cap.background.c.from</param-name>   
        <param-value>255,255,255</param-value>   
    </init-param>               
</servlet>   
<servlet-mapping>   
    <servlet-name>Captcha</servlet-name>   
    <url-pattern>/servlet/Captcha.jpg</url-pattern>   
</servlet-mapping>

html中增加<img style="border:0;" id="captchaImg" src="/servlet/Captcha.jpg" border="0"/>

验证码效果图片:

Java代码中可以通过req.getSession().getAttribute("SIMPLE_CAPCHA_SESSION_KEY")来取得验证码的值。

注意：

LINUX操作系统没有装x11的情况下，需要注释nl.captcha.text.imp.DefaultWordRenderer 类的

XML/HTML代码

/*
GraphicsEnvironment 
ge

 = 
GraphicsEnvironment

.getLocalGraphicsEnvironment();

   GraphicsDevice 
gd

 = 
ge

.getDefaultScreenDevice();
   GraphicsConfiguration 
gc

 = 
gd

.getDefaultConfiguration();
*/

/*   
GraphicsEnvironment ge = GraphicsEnvironment.getLocalGraphicsEnvironment();    
               
  GraphicsDevice gd = ge.getDefaultScreenDevice();    
  GraphicsConfiguration gc = gd.getDefaultConfiguration();    
*/

不然会有错误。

---------------------------------------------------------------------------------------------------------------------------

jsp验证码制作

　　介绍两个功能强大的开源制作验证码组件SimpleCaptcha，JCAPTCHA。

　　一、SimpleCaptcha搜狐邮箱注册时就使用了该组件，主页:
  http://simplecaptcha.sourceforge.net/index.html

1.配置
   将下载的jar文件放置工程的lib目录下，打开工程的web.xml文件加上相应的配置
<servlet>
   <servlet-name>Captcha</servlet-name>
   <servlet-class>nl.captcha.servlet.CaptchaServlet</servlet-class>
   <!--边框显示参数-->
   <init-param>
    <param-name>cap.border</param-name>
    <param-value>yes</param-value>
   </init-param>

   <!-- 设置图片边框色 -->
   <init-param>
    <param-name>cap.border.c</param-name>
    <param-value>green</param-value>
   </init-param>

   <!-- 边框粗细-->
   <init-param>
    <param-name>cap.border.th</param-name>
    <param-value>1</param-value>
   </init-param>

   <!-- the image producer. Currently only one-->
   <init-param>
    <param-name>cap.cap.producer</param-name>
    <param-value>
     nl.captcha.obscurity.imp.DefaultCaptchaIml
    </param-value>
   </init-param>

   <!-- 设置验证码的内容 -->
   <init-param>
    <param-name>cap.text.producer</param-name>
    <!--<param-value>Default</param-value>-->
    <!-- 此处是我自定义的一个显示中文的类 -->
    <param-value>org.ChineseTextProducer</param-value>
   </init-param>

   <!-- 此处可不定义，可在自定义类中定义所有的要显示的内容　-->
   <init-param>
    <param-name>cap.char.arr</param-name>
    <param-value>
     2,3,4,6,7,8,9,a,b,c,d,e,f,g,h,j,k,l,m,n,o,p,q,r,s,t,u,v,x,y,z
    </param-value>
   </init-param>

   <!-- 设置图片显示内容长度 -->
   <init-param>
    <param-name>cap.char.arr.l</param-name>
    <param-value>4</param-value>
   </init-param>

   <init-param>
    <param-name>cap.font.arr</param-name>
    <!-- 如果使用中文时设置成中文的字体 -->
    <param-value>
     Arial,Helvetica,Courier,TimesRoman,宋体,黑体
    </param-value>
   </init-param>

   <!-- 设置字体大小 -->
   <init-param>
    <param-name>cap.font.size</param-name>
    <param-value>30</param-value>
   </init-param>

   <!-- 设置图片字体色 -->
   <init-param>
    <param-name>cap.font.color</param-name>
    <param-value>white</param-value>
   </init-param>
  
   <!-- 扭曲; 曲解; 变形 begin -->
   <!-- 图片效果1
   <init-param>
    <param-name>cap.obscurificator</param-name>
    以下任选一
    <param-value>nl.captcha.obscurity.imp.ShadowGimpyImp</param-value>
    <param-value>nl.captcha.obscurity.imp.WaterRiple</param-value>
    <param-value>nl.captcha.sandbox.TestGimpyImp</param-value>
   </init-param>
   -->
   <init-param>
    <param-name>cap.obscurificator</param-name>
    <param-value>org.FishEyeGimpyImp</param-value>
   </init-param>

   <init-param>
    <param-name>cap.border</param-name>
    <param-value>no</param-value>
   </init-param>

   <init-param>
    <param-name>cap.char.arr.l</param-name>
    <param-value>6</param-value>
   </init-param>

   <init-param>
    <param-name>cap.background.c.to</param-name>
    <param-value>white</param-value>
   </init-param>
  
   <init-param>
    <param-name>cap.background.c.from</param-name>
    <param-value>white</param-value>
   </init-param>
   <!--扭曲; 曲解; 变形 end 不想要这种效果可注释以上代码-->

   <init-param>
    <param-name>cap.distortionImp</param-name>
    <param-value />
   </init-param>

   <init-param>
    <param-name>cap.backgroundImp</param-name>
    <param-value />
   </init-param>

   <!-- 此处色为渐变的色 -->
   <init-param>
    <param-name>cap.background.c.to</param-name>
    <param-value>black</param-value>
   </init-param>

   <!-- 图片左边色 -->
   <init-param>
    <param-name>cap.background.c.from</param-name>
    <param-value>black</param-value>
   </init-param>

   <!--干扰线实现类-->
   <init-param>
    <param-name>cap.noiseImp</param-name>
    <param-value>nl.captcha.obscurity.imp.DefaultNoiseImp</param-value>
   </init-param>

   <!-- 干扰线色
   <init-param>
    <param-name>cap.noise.c</param-name>
    <param-value>255,245,219</param-value>
   </init-param>
   -->
</servlet>
<servlet-mapping>
   <servlet-name>Captcha</servlet-name>
   <url-pattern>/Captcha.jpg</url-pattern>
</servlet-mapping>
   以上配置可根据喜好设置。

2、调用显示

在要显示验证码的页面中加入<img src="Captcha.jpg">即可显示生成的验证码

3、后台验证
验证非常简单，通过session.getAttribute(nl.captcha.servlet.Constants.SIMPLE_CAPCHA_SESSION_KEY);即可得到组件生成
的验证码，然后与前台传递的用户填写的内容比较即可。

注：如果要自定义验证码的内容可以继承DefaultTextCreator类，覆写getText()方法即可，方法返回的是一个字符串。

　　二、JCAPTCHA，该组件功能非常强大，可以生成word、图片、声音等验证码。主页：
http://forge.octo.com/jcaptcha/confluence/display/general/Home
http://jcaptcha.sourceforge.net/

更多实例可以查看：http://forge.octo.com/jcaptcha/confluence/display/general/Samples+tests

1、配置
下载JCAPTCHA后将jcaptcha.jar和commons-collections-2.1以上.jar(单独下载，地址：http://commons.apache.org/collections/ )放置工程lib目录下。

2、Implement a CaptchaService

import com.octo.captcha.service.image.ImageCaptchaService;
import com.octo.captcha.service.image.DefaultManageableImageCaptchaService;

public class CaptchaServiceSingleton {

     private static ImageCaptchaService instance = new DefaultManageableImageCaptchaService();

     public static ImageCaptchaService getInstance(){
        return instance;
    　　}
}

3、编写一个产生验证码的servlet

public class ImageCaptchaServlet extends HttpServlet {

protected void doGet(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse)
        throws ServletException, IOException {

        byte[] captchaChallengeAsJpeg = null;
     
        ByteArrayOutputStream jpegOutputStream = new ByteArrayOutputStream();
        try {
         String captchaId = httpServletRequest.getSession().getId();
       
        BufferedImage challenge =
                    CaptchaServiceSingleton.getInstance().getImageChallengeForID(captchaId,
                            httpServletRequest.getLocale());
            JPEGImageEncoder jpegEncoder = JPEGCodec.createJPEGEncoder(jpegOutputStream);
            jpegEncoder.encode(challenge);
        } catch (IllegalArgumentException e) {
            httpServletResponse.sendError(HttpServletResponse.SC_NOT_FOUND);
            return;
        } catch (CaptchaServiceException e) {
            httpServletResponse.sendError(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
            return;
        }

        captchaChallengeAsJpeg = jpegOutputStream.toByteArray();

        httpServletResponse.setHeader("Cache-Control", "no-store");
        httpServletResponse.setHeader("Pragma", "no-cache");
        httpServletResponse.setDateHeader("Expires", 0);
        httpServletResponse.setContentType("image/jpeg");
        ServletOutputStream responseOutputStream =
                httpServletResponse.getOutputStream();
        responseOutputStream.write(captchaChallengeAsJpeg);
        responseOutputStream.flush();
        responseOutputStream.close();
    }
}

4、将servlet添加到web.xml文件中
<servlet>
         <servlet-name>jcaptcha</servlet-name>
        <servlet-class>ImageCaptchaServlet</servlet-class>
         <load-on-startup>0</load-on-startup>
        </servlet>

<servlet-mapping>
        <servlet-name>jcaptcha</servlet-name>
         <url-pattern>/jcaptcha</url-pattern>
</servlet-mapping>

5、在页面中显示
<img src="jcaptcha">
<input type='text' name='captcha_code' value=''>

6、后台验证
Boolean isResponseCorrect =Boolean.FALSE;
        String captchaId = httpServletRequest.getSession().getId();
        String response = httpServletRequest.getParameter("captcha_code");
        try {
                isResponseCorrect = CaptchaServiceSingleton.getInstance().validateResponseForID(captchaId,response);
        } catch (CaptchaServiceException e) {
   //TODO
        }
最简单的开发过程结束，试运行一下效果！

注：要实现自己的验证引擎可以继承ListImageCaptchaEngine实现抽象方法buildInitialFactories()。

----------------------------------------------------------------------------------------------------------------------------

转 TestHTTPAuthServer.java

import nl.captcha. Captcha . Builder ;
import nl.captcha.obscurity.text.producer. TextProducer ;

        private byte [] createCaptchaImage(String captcha) {
                Builder b = new nl.captcha.Captcha .Builder (200 ,50 );
                b.addText(new MyTextProducer (captcha));
                b.addNoise();
                b.addNoise();
                b.gimp();
                b.addBackground();


                nl.captcha.Captcha c = b.build();

                ByteArrayOutputStream n = new ByteArrayOutputStream ();
                try {
                        ImageIO .write(c.getImage(), "PNG" , n);
                } catch (IOException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                }
                return n.toByteArray();
        }

        private class MyTextProducer implements TextProducer {

                private String txt;

                public MyTextProducer (String txt){
                        this .txt = txt;
                }

                public String getText() {
                        return txt;
                }

        }