1/*
2 * Copyright (c) 2014, 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
26package sun.security.jgss;
27
28import org.ietf.jgss.GSSContext;
29import org.ietf.jgss.GSSCredential;
30
31/**
32 * The extending point of basic JGSS-API.
33 * <p>
34 * If a module wants to extend basic JGSS-API classes, it should extends this
35 * class and register itself as "the extender" using the setExtender method.
36 * When various GSSManager.createXXX methods are called, they will call
37 * "the extender"'s wrap methods to create objects of extended types
38 * instead of basic types.
39 * <p>
40 * We have only one extension now defined in com.sun.security.jgss, and the
41 * registering process is triggered in {@link GSSManagerImpl} by calling
42 * Class.forName("com.sun.security.jgss.Extender"). Only GSSContext
43 * and GSSCredential are extended now.
44 * <p>
45 * The setExtender method should be called before any JGSS call.
46 */
47public class JgssExtender {
48
49    // "The extender"
50    private static volatile JgssExtender theOne = new JgssExtender();
51
52    /**
53     * Gets "the extender". GSSManager calls this method so that it can
54     * wrap basic objects into extended objects.
55     * @return the extender
56     */
57    public static JgssExtender getExtender() {
58        return theOne;
59    }
60
61    /**
62     * Set "the extender" so that GSSManager can create extended objects.
63     */
64    protected static void setExtender(JgssExtender theOne) {
65        JgssExtender.theOne = theOne;
66    }
67
68    /**
69     * Wraps a plain GSSCredential object into an extended type.
70     */
71    public GSSCredential wrap(GSSCredential cred) {
72        return cred;
73    }
74
75    /**
76     * Wraps a plain GSSContext object into an extended type.
77     */
78    public GSSContext wrap(GSSContext ctxt) {
79        return ctxt;
80    }
81}
82