GetPropertyAction.java revision 672:2bb058ce572e 
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
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24 */
25
26package 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:
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
51public 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 defaultVal 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}
89