jsp 자동가입 방지 이미지 생성

모든 파일과 설명은 http://forge.octo.com/jcaptcha/confluence/display/general/Developer+Documentation
이곳에서 확인 가능.

매이븐 2 를 사용하지 않았으므로 그 아래의 내용대로...

http://sourceforge.net/projects/jcaptcha/files/ 
에서 jcaptcha-all.jar 파일을 받고
http://commons.apache.org/downloads/download_collections.cgi
에서 commons-collection-3.2 혹은 상위 버전을 받아서
webcontent 밑의 WEB-INF 밑의 lib에 넣어 준다.

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;
    }
}

클래스 생성

import com.octo.captcha.service.CaptchaServiceException;
import com.sun.image.codec.jpeg.JPEGCodec;
import com.sun.image.codec.jpeg.JPEGImageEncoder;

import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.awt.image.BufferedImage;
import java.io.ByteArrayOutputStream;
import java.io.IOException;


public class ImageCaptchaServlet extends HttpServlet {


    public void init(ServletConfig servletConfig) throws ServletException {

        super.init(servletConfig);

    }


    protected void doGet(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse) 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 = httpServletRequest.getSession().getId();
        // call the ImageCaptchaService getChallenge method
            BufferedImage challenge =
                    CaptchaServiceSingleton.getInstance().getImageChallengeForID(captchaId,
                            httpServletRequest.getLocale());

            // a jpeg encoder
            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();

        // flush it in the response
        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();
    }
}

클래스 생성

web.xml에

<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>

추가

사용할 페이지에

<img src="/jcaptcha">
<input type='text' name='j_captcha_response' value=''>

추가


입력값과 이미지가 맞는지 확인할 다음 소스를 서블릿이나 적적한 곳에 삽입

Boolean isResponseCorrect =Boolean.FALSE;
           //remenber that we need an id to validate!
           String captchaId = httpServletRequest.getSession().getId();
           //retrieve the response
           String response = httpServletRequest.getParameter("j_captcha_response");
           // Call the Service method
            try {
                isResponseCorrect = CaptchaServiceSingleton.getInstance().validateResponseForID(captchaId,
                        response);
            } catch (CaptchaServiceException e) {
                 //should not happen, may be thrown if the id is not valid
            }

//do something according to the result!

해주면 끝... 이라고 나와있지만...

Could not initialize class CaptchaServiceSingleton
에러가 나네..... 살펴 보니

commons-logging.jar 파일이 라이브러리에 더 추가 되어야 함.

/////////////////////////////////////////////////////////

위의 자동생성 이미지 커스터마이징 부분

다음과 같은 클래스 하나 더 생성

public class MyImageCaptchaEngine extends ListImageCaptchaEngine {
     protected void buildInitialFactories() {
            WordGenerator wgen = new RandomWordGenerator("ABCDEFGHIJKLMNOPQRSTUVWXYZ123456789");
            RandomRangeColorGenerator cgen = new RandomRangeColorGenerator(
                 new int[] {0, 100},
                 new int[] {0, 100},
                 new int[] {0, 100});
            TextPaster textPaster = new RandomTextPaster(new Integer(7), new Integer(7), cgen, true);

            BackgroundGenerator backgroundGenerator = new FunkyBackgroundGenerator(new Integer(200), new Integer(100));

            Font[] fontsList = new Font[] {
                new Font("Arial", 0, 10),
                new Font("Tahoma", 0, 10),
                new Font("Verdana", 0, 10),
             };

             FontGenerator fontGenerator = new RandomFontGenerator(new Integer(20), new Integer(35), fontsList);

             WordToImage wordToImage = new ComposedWordToImage(fontGenerator, backgroundGenerator, textPaster);
             this.addFactory(new GimpyFactory(wgen, wordToImage));
     }
}

//위의 WordGenerator wgen = new RandomWordGenerator("ABCDEFGHIJKLMNOPQRSTUVWXYZ123456789"); 부분에서 따옴표 안쪽을 숫자만으로 바꾸면 숫자만으로 출력되며, 원하는 문자로 바꿀수 있음

그리고 싱글턴 클래스를 다음으로 수정
public class CaptchaServiceSingleton {
    private static ImageCaptchaService instance;
    static {
    instance = new DefaultManageableImageCaptchaService(
    new FastHashMapCaptchaStore(),
    new MyImageCaptchaEngine(),
    180,
    100000,
    75000);
    }
    public static ImageCaptchaService getInstance(){
        return instance;
    }
}

하면, 앞의 기본형보다 조금더 보기 좋은 이미지를 생성하게 됨