1 /* 2 * Copyright (c) 1999, 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.awt; 27 28 /** 29 * The AWTSecurityManager class provides the ability to secondarily 30 * index AppContext objects through SecurityManager extensions. 31 * As noted in AppContext.java, AppContexts are primarily indexed by 32 * ThreadGroup. In the case where the ThreadGroup doesn't provide 33 * enough information to determine AppContext (e.g. system threads), 34 * if a SecurityManager is installed which derives from 35 * AWTSecurityManager, the AWTSecurityManager's getAppContext() 36 * method is called to determine the AppContext. 37 * 38 * A typical example of the use of this class is where an applet 39 * is called by a system thread, yet the system AppContext is 40 * inappropriate, because applet code is currently executing. 41 * In this case, the getAppContext() method can walk the call stack 42 * to determine the applet code being executed and return the applet's 43 * AppContext object. 44 * 45 * @author Fred Ecks 46 */ 47 public class AWTSecurityManager extends SecurityManager { 48 49 /** 50 * Get the AppContext corresponding to the current context. 51 * The default implementation returns null, but this method 52 * may be overridden by various SecurityManagers 53 * (e.g. AppletSecurity) to index AppContext objects by the 54 * calling context. 55 * 56 * @return the AppContext corresponding to the current context. 57 * @see sun.awt.AppContext 58 * @see java.lang.SecurityManager 59 * @since 1.2.1 60 */ 61 public AppContext getAppContext() { 62 return null; // Default implementation returns null 63 } 64 65 } /* class AWTSecurityManager */