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 *
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
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24 */
25
26package java.security;
27
28import java.io.*;
29import java.security.spec.AlgorithmParameterSpec;
30import java.security.spec.InvalidParameterSpecException;
31
32/**
33 * This class defines the <i>Service Provider Interface</i> (<b>SPI</b>)
34 * for the {@code AlgorithmParameters} class, which is used to manage
35 * algorithm parameters.
36 *
37 * <p> All the abstract methods in this class must be implemented by each
38 * cryptographic service provider who wishes to supply parameter management
39 * for a particular algorithm.
40 *
41 * @author Jan Luehe
42 *
43 *
44 * @see AlgorithmParameters
45 * @see java.security.spec.AlgorithmParameterSpec
46 * @see java.security.spec.DSAParameterSpec
47 *
48 * @since 1.2
49 */
50
51public abstract class AlgorithmParametersSpi {
52
53    /**
54     * Initializes this parameters object using the parameters
55     * specified in {@code paramSpec}.
56     *
57     * @param paramSpec the parameter specification.
58     *
59     * @exception InvalidParameterSpecException if the given parameter
60     * specification is inappropriate for the initialization of this parameter
61     * object.
62     */
63    protected abstract void engineInit(AlgorithmParameterSpec paramSpec)
64        throws InvalidParameterSpecException;
65
66    /**
67     * Imports the specified parameters and decodes them
68     * according to the primary decoding format for parameters.
69     * The primary decoding format for parameters is ASN.1, if an ASN.1
70     * specification for this type of parameters exists.
71     *
72     * @param params the encoded parameters.
73     *
74     * @exception IOException on decoding errors
75     */
76    protected abstract void engineInit(byte[] params)
77        throws IOException;
78
79    /**
80     * Imports the parameters from {@code params} and
81     * decodes them according to the specified decoding format.
82     * If {@code format} is null, the
83     * primary decoding format for parameters is used. The primary decoding
84     * format is ASN.1, if an ASN.1 specification for these parameters
85     * exists.
86     *
87     * @param params the encoded parameters.
88     *
89     * @param format the name of the decoding format.
90     *
91     * @exception IOException on decoding errors
92     */
93    protected abstract void engineInit(byte[] params, String format)
94        throws IOException;
95
96    /**
97     * Returns a (transparent) specification of this parameters
98     * object.
99     * {@code paramSpec} identifies the specification class in which
100     * the parameters should be returned. It could, for example, be
101     * {@code DSAParameterSpec.class}, to indicate that the
102     * parameters should be returned in an instance of the
103     * {@code DSAParameterSpec} class.
104     *
105     * @param <T> the type of the parameter specification to be returned
106     *
107     * @param paramSpec the specification class in which
108     * the parameters should be returned.
109     *
110     * @return the parameter specification.
111     *
112     * @exception InvalidParameterSpecException if the requested parameter
113     * specification is inappropriate for this parameter object.
114     */
115    protected abstract
116        <T extends AlgorithmParameterSpec>
117        T engineGetParameterSpec(Class<T> paramSpec)
118        throws InvalidParameterSpecException;
119
120    /**
121     * Returns the parameters in their primary encoding format.
122     * The primary encoding format for parameters is ASN.1, if an ASN.1
123     * specification for this type of parameters exists.
124     *
125     * @return the parameters encoded using their primary encoding format.
126     *
127     * @exception IOException on encoding errors.
128     */
129    protected abstract byte[] engineGetEncoded() throws IOException;
130
131    /**
132     * Returns the parameters encoded in the specified format.
133     * If {@code format} is null, the
134     * primary encoding format for parameters is used. The primary encoding
135     * format is ASN.1, if an ASN.1 specification for these parameters
136     * exists.
137     *
138     * @param format the name of the encoding format.
139     *
140     * @return the parameters encoded using the specified encoding scheme.
141     *
142     * @exception IOException on encoding errors.
143     */
144    protected abstract byte[] engineGetEncoded(String format)
145        throws IOException;
146
147    /**
148     * Returns a formatted string describing the parameters.
149     *
150     * @return a formatted string describing the parameters.
151     */
152    protected abstract String engineToString();
153}
154