net.gplatform.sudoor.server.captcha.model.CaptchaEngine.java Source code

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Here is the source code for net.gplatform.sudoor.server.captcha.model.CaptchaEngine.java

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package net.gplatform.sudoor.server.captcha.model;

/*
 * #%L
 * sudoor-server-lib
 * %%
 * Copyright (C) 2013 - 2015 Shark Xu
 * %%
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as
 * published by the Free Software Foundation, either version 2 of the
 * License, or (at your option) any later version.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public
 * License along with this program.  If not, see
 * <http://www.gnu.org/licenses/gpl-2.0.html>.
 * #L%
 */

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 net.gplatform.sudoor.server.masterkey.MasterKey;

import org.apache.commons.lang3.StringUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;

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

/**
 * Remove Autowired Request & Sesssion due to the Autowired issue (Refer to
 * Autowired.txt)
 * 
 * @author xufucheng
 *
 */
@Component
public class CaptchaEngine {
    final Logger logger = LoggerFactory.getLogger(CaptchaEngine.class);

    @Autowired
    MasterKey masterKey;

    private Producer captchaProducer = null;

    @Autowired
    public void setCaptchaProducer(Producer captchaProducer) {
        this.captchaProducer = captchaProducer;
    }

    /**
     * 
     * @param request
     * @return
     */
    public boolean validate(HttpServletRequest request) {
        String captchaFromPage = request.getParameter("_captcha");
        HttpSession session = request.getSession();
        String captchaFromSession = (String) session.getAttribute(Constants.KAPTCHA_SESSION_KEY);

        logger.debug("CaptchaValidator: Session ID:{} captchaFromPage:{} captchaFromSession:{}", session.getId(),
                captchaFromPage, captchaFromSession);

        if (masterKey.checkWithMasterKey(captchaFromPage)) {
            return true;
        }

        if (StringUtils.equalsIgnoreCase(captchaFromSession, captchaFromPage)) {
            return true;
        }
        return false;
    }

    public void renderCapcha(HttpServletRequest request, HttpServletResponse response) throws Exception {
        // Set to expire far in the past.
        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
        request.getSession().setAttribute(Constants.KAPTCHA_SESSION_KEY, capText);
        logger.debug("Save Captcha: {} in Session:{}", capText, request.getSession().getId());

        // 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();
        }
    }
}