1/*
2 * Copyright (c) 1997, 2013, 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 *
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19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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24 */
25
26package javax.crypto;
27
28/**
29 * A secret (symmetric) key.
30 * The purpose of this interface is to group (and provide type safety
31 * for) all secret key interfaces.
32 * <p>
33 * Provider implementations of this interface must overwrite the
34 * {@code equals} and {@code hashCode} methods inherited from
35 * {@link java.lang.Object}, so that secret keys are compared based on
36 * their underlying key material and not based on reference.
37 * Implementations should override the default {@code destroy} and
38 * {@code isDestroyed} methods from the
39 * {@link javax.security.auth.Destroyable} interface to enable
40 * sensitive key information to be destroyed, cleared, or in the case
41 * where such information is immutable, unreferenced.
42 * Finally, since {@code SecretKey} is {@code Serializable}, implementations
43 * should also override
44 * {@link java.io.ObjectOutputStream#writeObject(java.lang.Object)}
45 * to prevent keys that have been destroyed from being serialized.
46 *
47 * <p>Keys that implement this interface return the string {@code RAW}
48 * as their encoding format (see {@code getFormat}), and return the
49 * raw key bytes as the result of a {@code getEncoded} method call. (The
50 * {@code getFormat} and {@code getEncoded} methods are inherited
51 * from the {@link java.security.Key} parent interface.)
52 *
53 * @author Jan Luehe
54 *
55 * @see SecretKeyFactory
56 * @see Cipher
57 * @since 1.4
58 */
59
60public interface SecretKey extends
61    java.security.Key, javax.security.auth.Destroyable {
62
63    /**
64     * The class fingerprint that is set to indicate serialization
65     * compatibility since J2SE 1.4.
66     */
67    static final long serialVersionUID = -4795878709595146952L;
68}
69