1 /*
   2  * Copyright (c) 1998, 2006, 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 sun.security.action;
  27 
  28 /**
  29  * A convenience class for retrieving the integer value of a system property
  30  * as a privileged action.
  31  *
  32  * <p>An instance of this class can be used as the argument of
  33  * <code>AccessController.doPrivileged</code>.
  34  *
  35  * <p>The following code retrieves the integer value of the system
  36  * property named <code>"prop"</code> as a privileged action. Since it does
  37  * not pass a default value to be used in case the property
  38  * <code>"prop"</code> is not defined, it has to check the result for
  39  * <code>null</code>:
  40  *
  41  * <pre>
  42  * Integer tmp = java.security.AccessController.doPrivileged
  43  *     (new sun.security.action.GetIntegerAction("prop"));
  44  * int i;
  45  * if (tmp != null) {
  46  *     i = tmp.intValue();
  47  * }
  48  * </pre>
  49  *
  50  * <p>The following code retrieves the integer value of the system
  51  * property named <code>"prop"</code> as a privileged action, and also passes
  52  * a default value to be used in case the property <code>"prop"</code> is not
  53  * defined:
  54  *
  55  * <pre>
  56  * int i = ((Integer)java.security.AccessController.doPrivileged(
  57  *                         new GetIntegerAction("prop", 3))).intValue();
  58  * </pre>
  59  *
  60  * @author Roland Schemers
  61  * @see java.security.PrivilegedAction
  62  * @see java.security.AccessController
  63  * @since 1.2
  64  */
  65 
  66 public class GetIntegerAction
  67         implements java.security.PrivilegedAction<Integer> {
  68     private String theProp;
  69     private int defaultVal;
  70     private boolean defaultSet = false;
  71 
  72     /**
  73      * Constructor that takes the name of the system property whose integer
  74      * value needs to be determined.
  75      *
  76      * @param theProp the name of the system property.
  77      */
  78     public GetIntegerAction(String theProp) {
  79         this.theProp = theProp;
  80     }
  81 
  82     /**
  83      * Constructor that takes the name of the system property and the default
  84      * value of that property.
  85      *
  86      * @param theProp the name of the system property.
  87      * @param defaultVal the default value.
  88      */
  89     public GetIntegerAction(String theProp, int defaultVal) {
  90         this.theProp = theProp;
  91         this.defaultVal = defaultVal;
  92         this.defaultSet = true;
  93     }
  94 
  95     /**
  96      * Determines the integer value of the system property whose name was
  97      * specified in the constructor.
  98      *
  99      * <p>If there is no property of the specified name, or if the property
 100      * does not have the correct numeric format, then an <code>Integer</code>
 101      * object representing the default value that was specified in the
 102      * constructor is returned, or <code>null</code> if no default value was
 103      * specified.
 104      *
 105      * @return the <code>Integer</code> value of the property.
 106      */
 107     public Integer run() {
 108         Integer value = Integer.getInteger(theProp);
 109         if ((value == null) && defaultSet)
 110             return defaultVal;
 111         return value;
 112     }
 113 }