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1   /* PropertyUtils.java
2    *
3    * Created Aug 4, 2005
4    *
5    * Copyright (C) 2005 Internet Archive.
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.util;
24  
25  /***
26   * @author stack
27   * @version $Date: 2005-08-15 23:35:10 +0000 (Mon, 15 Aug 2005) $ $Revision: 3760 $
28   */
29  public class PropertyUtils {
30      /****
31       * @param key Property key.
32       * @return Named property or null if the property is null or empty.
33       */
34      public static String getPropertyOrNull(final String key) {
35          String value = System.getProperty(key);
36          return (value == null || value.length() <= 0)? null: value;
37      }
38  
39      /****
40       * @param key Property key.
41       * @return Boolean value or false if null or unreadable.
42       */
43      public static boolean getBooleanProperty(final String key) {
44          return (getPropertyOrNull(key) == null)?
45                  false: Boolean.valueOf(getPropertyOrNull(key)).booleanValue();
46      }   
47      
48      /***
49       * @param key Key to use looking up system property.
50       * @param fallback If no value found for passed <code>key</code>, return
51       * <code>fallback</code>.
52       * @return Value of property or <code>fallback</code>.
53       */
54      public static int getIntProperty(final String key, final int fallback) {
55          return getPropertyOrNull(key) == null?
56                  fallback: Integer.parseInt(getPropertyOrNull(key));
57      }
58  }