1 /* HashFactory.java -- 2 Copyright (C) 2001, 2002, 2003, 2006 Free Software Foundation, Inc. 3 4 This file is a 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 of the License, or (at 9 your option) 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; if not, write to the Free Software 18 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 19 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.java.security.hash; 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 <i>Factory</i> to instantiate message digest algorithm instances. 49 */ 50 public class HashFactory 51 { 52 /** Trivial constructor to enforce <i>Singleton</i> pattern. */ HashFactory()53 private HashFactory() 54 { 55 super(); 56 } 57 58 /** 59 * Return an instance of a hash algorithm given its name. 60 * 61 * @param name the name of the hash algorithm. 62 * @return an instance of the hash algorithm, or null if none found. 63 * @exception InternalError if the implementation does not pass its self- 64 * test. 65 */ getInstance(String name)66 public static IMessageDigest getInstance(String name) 67 { 68 if (name == null) 69 return null; 70 71 name = name.trim(); 72 IMessageDigest result = null; 73 if (name.equalsIgnoreCase(Registry.WHIRLPOOL_HASH)) 74 result = new Whirlpool(); 75 else if (name.equalsIgnoreCase(Registry.RIPEMD128_HASH) 76 || name.equalsIgnoreCase(Registry.RIPEMD_128_HASH)) 77 result = new RipeMD128(); 78 else if (name.equalsIgnoreCase(Registry.RIPEMD160_HASH) 79 || name.equalsIgnoreCase(Registry.RIPEMD_160_HASH)) 80 result = new RipeMD160(); 81 else if (name.equalsIgnoreCase(Registry.SHA160_HASH) 82 || name.equalsIgnoreCase(Registry.SHA_1_HASH) 83 || name.equalsIgnoreCase(Registry.SHA1_HASH) 84 || name.equalsIgnoreCase(Registry.SHA_HASH)) 85 result = new Sha160(); 86 else if (name.equalsIgnoreCase(Registry.SHA256_HASH)) 87 result = new Sha256(); 88 else if (name.equalsIgnoreCase(Registry.SHA384_HASH)) 89 result = new Sha384(); 90 else if (name.equalsIgnoreCase(Registry.SHA512_HASH)) 91 result = new Sha512(); 92 else if (name.equalsIgnoreCase(Registry.TIGER_HASH)) 93 result = new Tiger(); 94 else if (name.equalsIgnoreCase(Registry.HAVAL_HASH)) 95 result = new Haval(); 96 else if (name.equalsIgnoreCase(Registry.MD5_HASH)) 97 result = new MD5(); 98 else if (name.equalsIgnoreCase(Registry.MD4_HASH)) 99 result = new MD4(); 100 else if (name.equalsIgnoreCase(Registry.MD2_HASH)) 101 result = new MD2(); 102 else if (name.equalsIgnoreCase(Registry.HAVAL_HASH)) 103 result = new Haval(); 104 105 if (result != null && ! result.selfTest()) 106 throw new InternalError(result.name()); 107 108 return result; 109 } 110 111 /** 112 * Returns a {@link Set} of names of hash algorithms supported by this 113 * <i>Factory</i>. 114 * 115 * @return a {@link Set} of hash names (Strings). 116 */ getNames()117 public static final Set getNames() 118 { 119 HashSet hs = new HashSet(); 120 hs.add(Registry.WHIRLPOOL_HASH); 121 hs.add(Registry.RIPEMD128_HASH); 122 hs.add(Registry.RIPEMD160_HASH); 123 hs.add(Registry.SHA160_HASH); 124 hs.add(Registry.SHA256_HASH); 125 hs.add(Registry.SHA384_HASH); 126 hs.add(Registry.SHA512_HASH); 127 hs.add(Registry.TIGER_HASH); 128 hs.add(Registry.HAVAL_HASH); 129 hs.add(Registry.MD5_HASH); 130 hs.add(Registry.MD4_HASH); 131 hs.add(Registry.MD2_HASH); 132 133 return Collections.unmodifiableSet(hs); 134 } 135 } 136