View Javadoc
1   /*
2    * Copyright (c) 2004, Oracle and/or its affiliates. All rights reserved.
3    * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4    *
5    * This code is free software; you can redistribute it and/or modify it
6    * under the terms of the GNU General Public License version 2 only, as
7    * published by the Free Software Foundation.  Oracle designates this
8    * particular file as subject to the "Classpath" exception as provided
9    * by Oracle in the LICENSE file that accompanied this code.
10   *
11   * This code is distributed in the hope that it will be useful, but WITHOUT
12   * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13   * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14   * version 2 for more details (a copy is included in the LICENSE file that
15   * accompanied this code).
16   *
17   * You should have received a copy of the GNU General Public License version
18   * 2 along with this work; if not, write to the Free Software Foundation,
19   * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20   *
21   * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22   * or visit www.oracle.com if you need additional information or have any
23   * questions.
24   */
25  
26  package com.sun.corba.se.impl.orbutil ;
27  
28  /**
29   * A convenience class for retrieving the string value of a system
30   * property as a privileged action.  This class is directly copied
31   * from sun.security.action.GetPropertyAction in order to avoid
32   * depending on the sun.security.action package.
33   *
34   * <p>An instance of this class can be used as the argument of
35   * <code>AccessController.doPrivileged</code>.
36   *
37   * <p>The following code retrieves the value of the system
38   * property named <code>"prop"</code> as a privileged action: <p>
39   *
40   * <pre>
41   * String s = (String) java.security.AccessController.doPrivileged(
42   *                         new GetPropertyAction("prop"));
43   * </pre>
44   *
45   * @author Roland Schemers
46   * @author Ken Cavanaugh
47   * @see java.security.PrivilegedAction
48   * @see java.security.AccessController
49   */
50  
51  public class GetPropertyAction implements java.security.PrivilegedAction {
52      private String theProp;
53      private String defaultVal;
54  
55      /**
56       * Constructor that takes the name of the system property whose
57       * string value needs to be determined.
58       *
59       * @param theProp the name of the system property.
60       */
61      public GetPropertyAction(String theProp) {
62          this.theProp = theProp;
63      }
64  
65      /**
66       * Constructor that takes the name of the system property and the default
67       * value of that property.
68       *
69       * @param theProp the name of the system property.
70       * @param defaulVal the default value.
71       */
72      public GetPropertyAction(String theProp, String defaultVal) {
73          this.theProp = theProp;
74          this.defaultVal = defaultVal;
75      }
76  
77      /**
78       * Determines the string value of the system property whose
79       * name was specified in the constructor.
80       *
81       * @return the string value of the system property,
82       *         or the default value if there is no property with that key.
83       */
84      public Object run() {
85          String value = System.getProperty(theProp);
86          return (value == null) ? defaultVal : value;
87      }
88  }