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   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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   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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  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).
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  25 
  26 package java.security.spec;
  27 
  28 /**
  29  * This class represents a public or private key in encoded format.
  30  *
  31  * @author Jan Luehe
  32  *
  33  *
  34  * @see java.security.Key
  35  * @see java.security.KeyFactory
  36  * @see KeySpec
  37  * @see X509EncodedKeySpec
  38  * @see PKCS8EncodedKeySpec
  39  *
  40  * @since 1.2
  41  */
  42 
  43 public abstract class EncodedKeySpec implements KeySpec {
  44 
  45     private byte[] encodedKey;
  46     private String algorithmName;
  47 
  48     /**
  49      * Creates a new {@code EncodedKeySpec} with the given encoded key.
  50      *
  51      * @param encodedKey the encoded key. The contents of the
  52      * array are copied to protect against subsequent modification.
  53      * @throws NullPointerException if {@code encodedKey}
  54      * is null.
  55      */
  56     public EncodedKeySpec(byte[] encodedKey) {
  57         this.encodedKey = encodedKey.clone();
  58     }
  59 
  60     /**
  61      * Creates a new {@code EncodedKeySpec} with the given encoded key.
  62      * This constructor is useful when subsequent callers of the
  63      * {@code EncodedKeySpec} object might not know the algorithm
  64      * of the key.
  65      *
  66      * @param encodedKey the encoded key. The contents of the
  67      * array are copied to protect against subsequent modification.
  68      * @param algorithm the algorithm name of the encoded key
  69      * See the KeyFactory section in the <a href=
  70      * "{@docRoot}/../technotes/guides/security/StandardNames.html#KeyFactory">
  71      * Java Cryptography Architecture Standard Algorithm Name Documentation</a>
  72      * for information about standard algorithm names.
  73      * @throws NullPointerException if {@code encodedKey}
  74      * or {@code algorithm} is null.
  75      * @throws IllegalArgumentException if {@code algorithm} is
  76      * the empty string {@code ""}
  77      * @since 1.9
  78      */
  79     protected EncodedKeySpec(byte[] encodedKey, String algorithm) {
  80         if (algorithm == null) {
  81             throw new NullPointerException("algorithm name may not be null");
  82         }
  83         if (algorithm.isEmpty()) {
  84             throw new IllegalArgumentException("algorithm name "
  85                                              + "may not be empty");
  86         }
  87         this.encodedKey = encodedKey.clone();
  88         this.algorithmName = algorithm;
  89 
  90     }
  91 
  92     /**
  93      * Returns the name of the algorithm of the encoded key.
  94      *
  95      * @return the name of the algorithm, or null if not specified
  96      * @since 1.9
  97      */
  98     public String getAlgorithm() {
  99         return algorithmName;
 100     }
 101 
 102     /**
 103      * Returns the encoded key.
 104      *
 105      * @return the encoded key. Returns a new array each time
 106      * this method is called.
 107      */
 108     public byte[] getEncoded() {
 109         return this.encodedKey.clone();
 110     }
 111 
 112     /**
 113      * Returns the name of the encoding format associated with this
 114      * key specification.
 115      *
 116      * <p>If the opaque representation of a key
 117      * (see {@link java.security.Key Key}) can be transformed
 118      * (see {@link java.security.KeyFactory KeyFactory})
 119      * into this key specification (or a subclass of it),
 120      * {@code getFormat} called
 121      * on the opaque key returns the same value as the
 122      * {@code getFormat} method
 123      * of this key specification.
 124      *
 125      * @return a string representation of the encoding format.
 126      */
 127     public abstract String getFormat();
 128 }