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1
55 package org.jboss.axis.utils;
56
57 import org.jboss.logging.Logger;
58
59 import java.security.MessageDigest  ;
60 import java.security.NoSuchAlgorithmException ;
61 import java.util.Random ;
62
63
66 public class SessionUtils
67 {
68
69
72 private static Logger log = Logger.getLogger(SessionUtils.class.getName());
73
74
78 protected static final String DEFAULT_ALGORITHM = "MD5";
79
80
84 protected static final int SESSION_ID_BYTES = 16;
85
86
91 protected static String algorithm = DEFAULT_ALGORITHM;
92
93
97 protected static MessageDigest digest = null;
98
99
102 protected static Random random = null;
103
104
108 protected static String randomClass = "java.security.SecureRandom";
109
110
113 private static String thisHost = null;
114
115
120 public static synchronized String generateSessionId()
121 {
122 byte bytes[] = new byte[SESSION_ID_BYTES];
124
125 getRandom().nextBytes(bytes);
126 bytes = getDigest().digest(bytes);
127
128 StringBuffer result = new StringBuffer ();
130
131 for (int i = 0; i < bytes.length; i++)
132 {
133 byte b1 = (byte)((bytes[i] & 0xf0) >> 4);
134 byte b2 = (byte)(bytes[i] & 0x0f);
135
136 if (b1 < 10)
137 {
138 result.append((char)('0' + b1));
139 }
140 else
141 {
142 result.append((char)('A' + (b1 - 10)));
143 }
144 if (b2 < 10)
145 {
146 result.append((char)('0' + b2));
147 }
148 else
149 {
150 result.append((char)('A' + (b2 - 10)));
151 }
152 }
153 return (result.toString());
154 }
155
156
161 public static synchronized Long generateSession()
162 {
163 return new Long (getRandom().nextLong());
164 }
165
166
173 private static synchronized MessageDigest getDigest()
174 {
175 if (digest == null)
176 {
177 try
178 {
179 digest = MessageDigest.getInstance(algorithm);
180 }
181 catch (NoSuchAlgorithmException e)
182 {
183 try
184 {
185 digest = MessageDigest.getInstance(DEFAULT_ALGORITHM);
186 }
187 catch (NoSuchAlgorithmException f)
188 {
189 digest = null;
190 }
191 }
192 }
193 return (digest);
194 }
195
196
203 private static synchronized Random getRandom()
204 {
205 if (random == null)
206 {
207 try
208 {
209 Class clazz = Class.forName(randomClass);
210
211 random = (Random )clazz.newInstance();
212 long seed = System.currentTimeMillis();
213 char entropy[] = getEntropy().toCharArray();
214
215 for (int i = 0; i < entropy.length; i++)
216 {
217 long update = ((byte)entropy[i]) << ((i % 8) * 8);
218
219 seed ^= update;
220 }
221 random.setSeed(seed);
222 }
223 catch (Exception e)
224 {
225 random = new java.util.Random ();
226 }
227 }
228 return (random);
229 }
230
231
236 private static String getEntropy()
237 {
238 if (null == thisHost)
239 {
240 try
241 {
242 thisHost = java.net.InetAddress.getLocalHost().getHostName();
243 }
244 catch (java.net.UnknownHostException e)
245 {
246 log.error(Messages.getMessage("javaNetUnknownHostException00"),
247 e);
248 thisHost = "localhost";
249 }
250 }
251 StringBuffer s = new StringBuffer ();
252
253 s.append(s.hashCode()).append('.').append(System.currentTimeMillis())
255 .append(".AXIS@").append(thisHost);
256 return s.toString();
257 }
258 }
259 |
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