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    1   /* ImageWaitEvaluator
    2    *
    3    * $Id: ImageWaitEvaluator.java 4667 2006-09-26 20:38:48Z paul_jack $
    4    *
    5    * Created on 1.4.2005
    6    *
    7    * Copyright (C) 2005 Internet Archive.
    8    *
    9    * This file is part of the Heritrix web crawler (crawler.archive.org).
    10   *
    11   * Heritrix is free software; you can redistribute it and/or modify
    12   * it under the terms of the GNU Lesser Public License as published by
    13   * the Free Software Foundation; either version 2.1 of the License, or
    14   * any later version.
    15   *
    16   * Heritrix is distributed in the hope that it will be useful,
    17   * but WITHOUT ANY WARRANTY; without even the implied warranty of
    18   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    19   * GNU Lesser Public License for more details.
    20   *
    21   * You should have received a copy of the GNU Lesser Public License
    22   * along with Heritrix; if not, write to the Free Software
    23   * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
    24   */
    25  package org.archive.crawler.postprocessor;
    26
    27  /***
    28   * A specialized ContentBasedWaitEvaluator. Comes preset with a regular
    29   * expression that matches text documents. <code>^image/.*$</code>
    30   *
    31   * @author Kristinn Sigurdsson
    32   *
    33   * @see org.archive.crawler.postprocessor.ContentBasedWaitEvaluator
    34   */
    35  public class ImageWaitEvaluator extends ContentBasedWaitEvaluator {
    36
    37      private static final long serialVersionUID = -2762377129860398333L;
    38
    39      protected final static Long DEFAULT_INITIAL_WAIT_INTERVAL =
    40          new Long(172800); // 2 days
    41
    42      protected final static String DEFAULT_CONTENT_REGEXPR = "^image/.*$"; //Text
    43
    44      /***
    45       * Constructor
    46       *
    47       * @param name The name of the module
    48       */
    49      public ImageWaitEvaluator(String name) {
    50          super(name,"Evaluates how long to wait before fetching a URI again. " +
    51                  "Only handles CrawlURIs whose content type indicates a " +
    52                  "image document (^image/.*$). " +
    53                  "Typically, this processor should be in the post processing " +
    54                  "chain. It will pass if another wait evaluator has already " +
    55                  "processed the CrawlURI.",
    56                  DEFAULT_CONTENT_REGEXPR,
    57                  DEFAULT_INITIAL_WAIT_INTERVAL,
    58                  DEFAULT_MAX_WAIT_INTERVAL,
    59                  DEFAULT_MIN_WAIT_INTERVAL,
    60                  DEFAULT_UNCHANGED_FACTOR,
    61                  DEFAULT_CHANGED_FACTOR);
    62      }
    63
    64
    65  }