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      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>: <p>
     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: <p>
     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 defaulVal 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 new Integer(defaultVal);
    111         return value;
    112     }
    113 }
    114