1 /*
   2  * Copyright (c) 1997, 1999, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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   5  * This code is free software; you can redistribute it and/or modify it
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   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.
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  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
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  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
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  23  * questions.
  24  */
  25 
  26 package java.security;
  27 
  28 import java.security.spec.AlgorithmParameterSpec;
  29 
  30 /**
  31  * This class defines the <i>Service Provider Interface</i> (<b>SPI</b>)
  32  * for the <code>AlgorithmParameterGenerator</code> class, which
  33  * is used to generate a set of parameters to be used with a certain algorithm.
  34  *
  35  * <p> All the abstract methods in this class must be implemented by each
  36  * cryptographic service provider who wishes to supply the implementation
  37  * of a parameter generator for a particular algorithm.
  38  *
  39  * <p> In case the client does not explicitly initialize the
  40  * AlgorithmParameterGenerator (via a call to an <code>engineInit</code>
  41  * method), each provider must supply (and document) a default initialization.
  42  * For example, the Sun provider uses a default modulus prime size of 1024
  43  * bits for the generation of DSA parameters.
  44  *
  45  * @author Jan Luehe
  46  *
  47  *
  48  * @see AlgorithmParameterGenerator
  49  * @see AlgorithmParameters
  50  * @see java.security.spec.AlgorithmParameterSpec
  51  *
  52  * @since 1.2
  53  */
  54 
  55 public abstract class AlgorithmParameterGeneratorSpi {
  56 
  57     /**
  58      * Initializes this parameter generator for a certain size
  59      * and source of randomness.
  60      *
  61      * @param size the size (number of bits).
  62      * @param random the source of randomness.
  63      */
  64     protected abstract void engineInit(int size, SecureRandom random);
  65 
  66     /**
  67      * Initializes this parameter generator with a set of
  68      * algorithm-specific parameter generation values.
  69      *
  70      * @param genParamSpec the set of algorithm-specific parameter generation values.
  71      * @param random the source of randomness.
  72      *
  73      * @exception InvalidAlgorithmParameterException if the given parameter
  74      * generation values are inappropriate for this parameter generator.
  75      */
  76     protected abstract void engineInit(AlgorithmParameterSpec genParamSpec,
  77                                        SecureRandom random)
  78         throws InvalidAlgorithmParameterException;
  79 
  80     /**
  81      * Generates the parameters.
  82      *
  83      * @return the new AlgorithmParameters object.
  84      */
  85     protected abstract AlgorithmParameters engineGenerateParameters();
  86 }