libjava/classpath/javax/crypto/KeyGeneratorSpi.java

   1 /* KeyGeneratorSpi.java -- The key generator service provider interface.
   2    Copyright (C) 2004  Free Software Foundation, Inc.
   3
   4 This file is part of GNU Classpath.
   5
   6 GNU Classpath is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2, or (at your option)
   9 any later version.
  10
  11 GNU Classpath is distributed in the hope that it will be useful, but
  12 WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU Classpath; see the file COPYING.  If not, write to the
  18 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  19 02110-1301 USA.
  20
  21 Linking this library statically or dynamically with other modules is
  22 making a combined work based on this library.  Thus, the terms and
  23 conditions of the GNU General Public License cover the whole
  24 combination.
  25
  26 As a special exception, the copyright holders of this library give you
  27 permission to link this library with independent modules to produce an
  28 executable, regardless of the license terms of these independent
  29 modules, and to copy and distribute the resulting executable under
  30 terms of your choice, provided that you also meet, for each linked
  31 independent module, the terms and conditions of the license of that
  32 module.  An independent module is a module which is not derived from
  33 or based on this library.  If you modify this library, you may extend
  34 this exception to your version of the library, but you are not
  35 obligated to do so.  If you do not wish to do so, delete this
  36 exception statement from your version. */
  37
  38
  39 package javax.crypto;
  40
  41 import java.security.InvalidAlgorithmParameterException;
  42 import java.security.SecureRandom;
  43 import java.security.spec.AlgorithmParameterSpec;
  44
  45 /**
  46  * The <i>Service Provider Interface</i> (<b>SPI</b>) for the {@link
  47  * KeyGenerator} class.
  48  *
  49  * <p>Providers wishing to implement a key generator must subclass this
  50  * and provide an appropriate implementation for all the abstract
  51  * methods below, and provide an appropriate entry in the master {@link
  52  * java.security.Provider} class (the service name for key generators is
  53  * <code>"KeyGenerator"</code>).
  54  *
  55  * @author Casey Marshall (csm@gnu.org)
  56  * @since 1.4
  57  * @see KeyGenerator
  58  */
  59 public abstract class KeyGeneratorSpi
  60 {
  61
  62   // Constructor.
  63   // ------------------------------------------------------------------------
  64
  65   /** Create a new key generator SPI. */
  66   public KeyGeneratorSpi()
  67   {
  68   }
  69
  70   // Abstract instance methods.
  71   // ------------------------------------------------------------------------
  72
  73   /**
  74    * Generate a key, returning it as a {@link SecretKey}.
  75    *
  76    * @return The generated key.
  77    */
  78   protected abstract SecretKey engineGenerateKey();
  79
  80   /**
  81    * Initialize this key generator with parameters and a source of
  82    * randomness.
  83    *
  84    * @param params The parameters.
  85    * @param random The source of randomness.
  86    * @throws java.security.InvalidAlgorithmParameterException If the
  87    *         parameters are inappropriate for this instance.
  88    */
  89   protected abstract void engineInit(AlgorithmParameterSpec params,
  90                                      SecureRandom random)
  91     throws InvalidAlgorithmParameterException;
  92
  93   /**
  94    * Initialize this key generator with a key size (in bits) and a
  95    * source of randomness.
  96    *
  97    * @param keySize The target key size, in bits.
  98    * @param random  The source of randomness.
  99    * @throws java.security.InvalidParameterException If the
 100    *         key size is illogical or unsupported.
 101    */
 102   protected abstract void engineInit(int keySize, SecureRandom random);
 103
 104   /**
 105    * Initialize this key generator with a source of randomness; the
 106    * implementation should use reasonable default parameters (such as
 107    * generated key size).
 108    *
 109    * @param random The source of randomness.
 110    */
 111   protected abstract void engineInit(SecureRandom random);
 112 }