/* * Copyright (c) 1998, 2017, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package sun.security.action; import java.security.AccessController; import java.security.PrivilegedAction; /** * A convenience class for retrieving the string value of a system * property as a privileged action. * *

An instance of this class can be used as the argument of * AccessController.doPrivileged. * *

The following code retrieves the value of the system * property named "prop" as a privileged action:

* *

 * String s = java.security.AccessController.doPrivileged
 *                      (new GetPropertyAction("prop"));
 * 
* * @author Roland Schemers * @see java.security.PrivilegedAction * @see java.security.AccessController * @since 1.2 */ public class GetPropertyAction implements PrivilegedAction { private String theProp; private String defaultVal; /** * Constructor that takes the name of the system property whose * string value needs to be determined. * * @param theProp the name of the system property. */ public GetPropertyAction(String theProp) { this.theProp = theProp; } /** * Constructor that takes the name of the system property and the default * value of that property. * * @param theProp the name of the system property. * @param defaulVal the default value. */ public GetPropertyAction(String theProp, String defaultVal) { this.theProp = theProp; this.defaultVal = defaultVal; } /** * Determines the string value of the system property whose * name was specified in the constructor. * * @return the string value of the system property, * or the default value if there is no property with that key. */ public String run() { String value = System.getProperty(theProp); return (value == null) ? defaultVal : value; } /** * Convenience method to get a property without going through doPrivileged * if no security manager is present. This is unsafe for inclusion in a * public API but allowable here since this class is by default restricted * by the package.access security property. * * Note that this method performs a privileged action using caller-provided * inputs. The caller of this method should take care to ensure that the * inputs are not tainted and the returned property is not made accessible * to untrusted code if it contains sensitive information. * * @param theProp the name of the system property. */ public static String privilegedGetProperty(String theProp) { if (System.getSecurityManager() == null) { return System.getProperty(theProp); } else { return AccessController.doPrivileged( new GetPropertyAction(theProp)); } } /** * Convenience method to get a property without going through doPrivileged * if no security manager is present. This is unsafe for inclusion in a * public API but allowable here since this class is now encapsulated. * * Note that this method performs a privileged action using caller-provided * inputs. The caller of this method should take care to ensure that the * inputs are not tainted and the returned property is not made accessible * to untrusted code if it contains sensitive information. * * @param theProp the name of the system property. * @param defaultVal the default value. */ public static String privilegedGetProperty(String theProp, String defaultVal) { if (System.getSecurityManager() == null) { return System.getProperty(theProp, defaultVal); } else { return AccessController.doPrivileged( new GetPropertyAction(theProp, defaultVal)); } } }