1 /* KeyWrappingAlgorithmFactory.java -- FIXME: briefly describe file purpose 2 Copyright (C) 2006 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 gnu.javax.crypto.kwa; 40 41 import gnu.java.security.Registry; 42 43 import java.util.Collections; 44 import java.util.HashSet; 45 import java.util.Set; 46 47 /** 48 * A Factory class for the Key Wrapping Algorithm implementations. 49 */ 50 public class KeyWrappingAlgorithmFactory 51 { 52 /** Names of Key Wrapping Algorihms cached for speed. */ 53 private static Set names; 54 55 /** Trivial constructor to enforce Singleton pattern. */ KeyWrappingAlgorithmFactory()56 private KeyWrappingAlgorithmFactory() 57 { 58 super(); 59 } 60 61 /** 62 * Returns an instance of a key-wrapping algorithm given its name. 63 * 64 * @param name the case-insensitive name of the key-wrapping algorithm. 65 * @return an instance of the designated key-wrapping algorithm, or 66 * <code>null</code> if none was found. 67 * @exception InternalError if the implementation does not pass its self-test. 68 */ getInstance(String name)69 public static final IKeyWrappingAlgorithm getInstance(String name) 70 { 71 if (name == null) 72 return null; 73 name = name.trim(); 74 IKeyWrappingAlgorithm result = null; 75 if (name.equalsIgnoreCase(Registry.AES_KWA) 76 || name.equalsIgnoreCase(Registry.AES128_KWA) 77 || name.equalsIgnoreCase(Registry.AES192_KWA) 78 || name.equalsIgnoreCase(Registry.AES256_KWA) 79 || name.equalsIgnoreCase(Registry.RIJNDAEL_KWA)) 80 result = new AESKeyWrap(); 81 else if (name.equalsIgnoreCase(Registry.TRIPLEDES_KWA) 82 || name.equalsIgnoreCase(Registry.DESEDE_KWA)) 83 result = new TripleDESKeyWrap(); 84 85 return result; 86 } 87 88 /** 89 * Returns a {@link Set} of key wrapping algorithm names supported by this 90 * <i>Factory</i>. 91 * 92 * @return a {@link Set} of key wrapping algorithm names (Strings). 93 */ getNames()94 public static synchronized final Set getNames() 95 { 96 if (names == null) 97 { 98 HashSet hs = new HashSet(); 99 hs.add(Registry.AES_KWA); 100 hs.add(Registry.AES128_KWA); 101 hs.add(Registry.AES192_KWA); 102 hs.add(Registry.AES256_KWA); 103 hs.add(Registry.RIJNDAEL_KWA); 104 hs.add(Registry.TRIPLEDES_KWA); 105 hs.add(Registry.DESEDE_KWA); 106 names = Collections.unmodifiableSet(hs); 107 } 108 return names; 109 } 110 } 111