    1   /* $Id: ExceedsDocumentLengthTresholdDecideRule.java 4649 2006-09-25 17:16:55Z paul_jack $
    2    *
    3    * Created on 28.8.2006
    4    *
    5    * Copyright (C) 2006 Olaf Freyer
    6    *
    7    * This file is part of the Heritrix web crawler (crawler.archive.org).
    8    *
    9    * Heritrix is free software; you can redistribute it and/or modify
    10   * it under the terms of the GNU Lesser Public License as published by
    11   * the Free Software Foundation; either version 2.1 of the License, or
    12   * any later version.
    13   *
    14   * Heritrix is distributed in the hope that it will be useful,
    15   * but WITHOUT ANY WARRANTY; without even the implied warranty of
    16   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    17   * GNU Lesser Public License for more details.
    18   *
    19   * You should have received a copy of the GNU Lesser Public License
    20   * along with Heritrix; if not, write to the Free Software
    21   * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
    22   */
    23  package org.archive.crawler.deciderules;
    24
    25  import org.archive.crawler.settings.SimpleType;
    26
    27  public class ExceedsDocumentLengthTresholdDecideRule extends
    28  NotExceedsDocumentLengthTresholdDecideRule {
    29
    30      private static final long serialVersionUID = -3008503096295212224L;
    31
    32      /***
    33       * Usual constructor.
    34       * @param name Name of this rule.
    35       */
    36      public ExceedsDocumentLengthTresholdDecideRule(String name) {
    37      	super(name);
    38      	setDescription("ExceedsDocumentLengthTresholdDecideRule. ACCEPTs URIs "+
    39               "with content length exceeding a given treshold. "+
    40               "Either examines HTTP header content length or " +
    41               "actual downloaded content length and returns false " +
    42               "for documents exceeding a given length treshold.");
    43
    44          addElementToDefinition(new SimpleType(ATTR_CONTENT_LENGTH_TRESHOLD,
    45          	"Min " +
    46      	    "content-length this filter will allow to pass through. If -1, " +
    47      	    "then no limit.", DEFAULT_CONTENT_LENGTH_TRESHOLD));    }
    48
    49      /***
    50       * @param contentLength content length to check against treshold
    51       * @param obj Context object.
    52       * @return contentLength exceeding treshold?
    53       */
    54      protected Boolean makeDecision(int contentLength, Object obj) {
    55      	return contentLength > getContentLengthTreshold(obj);
    56      }
    57
    58      /***
    59       * @param obj Context object.
    60       * @return content length threshold
    61       */
    62      protected int getContentLengthTreshold(Object obj) {
    63          int len = ((Integer)getUncheckedAttribute(obj,
    64          		ATTR_CONTENT_LENGTH_TRESHOLD)).intValue();
    65          return len == -1? 0: len;
    66      }
    67  }