imagedominancescanner.java

spam source codejasen-0.9jASEN - java Anti Spam ENgine.zip 如标题所示

/*
 * @(#)ImageDominanceScanner.java	30/10/2004
 *
 * Copyright (c) 2004, 2005  jASEN.org
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *   1. Redistributions of source code must retain the above copyright notice,
 *      this list of conditions and the following disclaimer.
 *
 *   2. Redistributions in binary form must reproduce the above copyright
 *      notice, this list of conditions and the following disclaimer in
 *      the documentation and/or other materials provided with the distribution.
 *
 *   3. The names of the authors may not be used to endorse or promote products
 *      derived from this software without specific prior written permission.
 *
 *   4. Any modification or additions to the software must be contributed back
 *      to the project.
 *
 *   5. Any investigation or reverse engineering of source code or binary to
 *      enable emails to bypass the filters, and hence inflict spam and or viruses
 *      onto users who use or do not use jASEN could subject the perpetrator to
 *      criminal and or civil liability.
 *
 * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESSED OR IMPLIED WARRANTIES,
 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
 * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL JASEN.ORG,
 * OR ANY CONTRIBUTORS TO THIS SOFTWARE BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
 * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
 * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 */
package org.jasen.plugins;

import java.util.Properties;

import javax.mail.internet.MimeMessage;

import org.jasen.core.ProbabilityTestResult;
import org.jasen.core.StandardParserData;
import org.jasen.core.engine.Jasen;
import org.jasen.error.JasenException;
import org.jasen.interfaces.JasenMessage;
import org.jasen.interfaces.JasenPlugin;
import org.jasen.interfaces.JasenTestResult;
import org.jasen.interfaces.ParserData;
import org.jasen.interfaces.ReceivedHeaderParser;

/**
 * <P>
 * Tests for high ratios of images vs text.
 * </P>
 *
 * @author Jason Polites
 */
public class ImageDominanceScanner implements JasenPlugin
{
    private float lowProb = 0.4f;
    private float highProb = 0.9f;
    private float ratio = 1.0f;

    private int wordSize = 12;

    /**
     *
     */
    public ImageDominanceScanner() {
        super ();
    }

    /*
     * (non-Javadoc)
     *
     * @see org.jasen.interfaces.JasenPlugin#init(java.util.Properties)
     */
    public void init(Properties properties) throws JasenException {
        if (properties != null)
        {
            String strHi = properties.getProperty ("max");
            String strLo = properties.getProperty ("min");
            String strRatio = properties.getProperty ("ratio");

            if (strHi != null)
                highProb = Float.parseFloat (strHi);

            if (strLo != null)
                lowProb = Float.parseFloat (strLo);

            if (strRatio != null)
                ratio = Float.parseFloat (strRatio);

        }
    }

    /*
     * (non-Javadoc)
     * @see org.jasen.interfaces.JasenPlugin#destroy()
     */
    public void destroy() throws JasenException {}

    /*
     *  (non-Javadoc)
     * @see org.jasen.interfaces.JasenPlugin#test(org.jasen.core.Jasen, javax.mail.internet.MimeMessage, org.jasen.interfaces.JasenMessage, org.jasen.interfaces.ParserData, org.jasen.interfaces.ReceivedHeaderParser)
     */
    public JasenTestResult test(Jasen engine, MimeMessage rawMessage, JasenMessage parsedMessage, ParserData data, ReceivedHeaderParser parser) throws JasenException {
        ProbabilityTestResult result = new ProbabilityTestResult ();

        // Num words...(only look in html)
        int numHtmlWords = 0;
        int numImages = 0;

        // For performance reasons, we aren't going to bother splitting, removing stop words etc
        // Instead, we simply assume that the total chars represents a number of average sized 
        // words
        if(data.getHtmlAsText() != null) {
            numHtmlWords = data.getHtmlAsText().length() / wordSize; // average word size
            
        }

        if(data instanceof StandardParserData) {
            numImages = ((StandardParserData)data).getImageCount();
        }

        if(numImages == 0) {
            result.setProbability(lowProb);
        }
        else if (numHtmlWords == 0) {
            result.setProbability(highProb);
        }
        else {
            float prob = (((float)numImages / (float)numHtmlWords));

            if(prob >= ratio) {
                result.setProbability(highProb);
            }
            else if(prob <= lowProb) {
                result.setProbability(lowProb);
            }
            else {
                result.setProbability(prob);
            }
        }

        return result;
    }

}