| /* |
| * Copyright (c) 1997, 2013, 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 java.security; |
| |
| /** |
| * A GuardedObject is an object that is used to protect access to |
| * another object. |
| * |
| * <p>A GuardedObject encapsulates a target object and a Guard object, |
| * such that access to the target object is possible |
| * only if the Guard object allows it. |
| * Once an object is encapsulated by a GuardedObject, |
| * access to that object is controlled by the {@code getObject} |
| * method, which invokes the |
| * {@code checkGuard} method on the Guard object that is |
| * guarding access. If access is not allowed, |
| * an exception is thrown. |
| * |
| * @see Guard |
| * @see Permission |
| * |
| * @author Roland Schemers |
| * @author Li Gong |
| */ |
| |
| public class GuardedObject implements java.io.Serializable { |
| |
| private static final long serialVersionUID = -5240450096227834308L; |
| |
| private Object object; // the object we are guarding |
| private Guard guard; // the guard |
| |
| /** |
| * Constructs a GuardedObject using the specified object and guard. |
| * If the Guard object is null, then no restrictions will |
| * be placed on who can access the object. |
| * |
| * @param object the object to be guarded. |
| * |
| * @param guard the Guard object that guards access to the object. |
| */ |
| |
| public GuardedObject(Object object, Guard guard) |
| { |
| this.guard = guard; |
| this.object = object; |
| } |
| |
| /** |
| * Retrieves the guarded object, or throws an exception if access |
| * to the guarded object is denied by the guard. |
| * |
| * @return the guarded object. |
| * |
| * @exception SecurityException if access to the guarded object is |
| * denied. |
| */ |
| public Object getObject() |
| throws SecurityException |
| { |
| if (guard != null) |
| guard.checkGuard(object); |
| |
| return object; |
| } |
| |
| /** |
| * Writes this object out to a stream (i.e., serializes it). |
| * We check the guard if there is one. |
| */ |
| private void writeObject(java.io.ObjectOutputStream oos) |
| throws java.io.IOException |
| { |
| if (guard != null) |
| guard.checkGuard(object); |
| |
| oos.defaultWriteObject(); |
| } |
| } |