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1
55
56
62
63 package org.jboss.axis.components.uuid;
64
65 import java.math.BigInteger  ;
66 import java.security.SecureRandom ;
67 import java.util.Random ;
68
69
78 public class SimpleUUIDGen implements UUIDGen
79 {
80 private static final BigInteger countStart = new BigInteger ("-12219292800000"); private static final int clock_sequence = (new Random ()).nextInt(16384);
82
83
92 public String nextUUID()
93 {
94
97 BigInteger count;
99
100 BigInteger current = BigInteger.valueOf(System.currentTimeMillis());
102
103 BigInteger countMillis = current.subtract(countStart);
105
106 count = countMillis.multiply(BigInteger.valueOf(10000));
108
109 String bitString = count.toString(2);
110 if (bitString.length() < 60)
111 {
112 int nbExtraZeros = 60 - bitString.length();
113 String extraZeros = new String ();
114 for (int i = 0; i < nbExtraZeros; i++)
115 extraZeros = extraZeros.concat("0");
116
117 bitString = extraZeros.concat(bitString);
118 }
119
120 byte[] bits = bitString.getBytes();
121
122 byte[] time_low = new byte[32];
124 for (int i = 0; i < 32; i++)
125 time_low[i] = bits[bits.length - i - 1];
126
127 byte[] time_mid = new byte[16];
129 for (int i = 0; i < 16; i++)
130 time_mid[i] = bits[bits.length - 32 - i - 1];
131
132 byte[] time_hi_and_version = new byte[16];
134 for (int i = 0; i < 12; i++)
135 time_hi_and_version[i] = bits[bits.length - 48 - i - 1];
136
137 time_hi_and_version[12] = ((new String ("1")).getBytes())[0];
138 time_hi_and_version[13] = ((new String ("0")).getBytes())[0];
139 time_hi_and_version[14] = ((new String ("0")).getBytes())[0];
140 time_hi_and_version[15] = ((new String ("0")).getBytes())[0];
141
142 BigInteger clockSequence = BigInteger.valueOf(clock_sequence);
144 String clockString = clockSequence.toString(2);
145 if (clockString.length() < 14)
146 {
147 int nbExtraZeros = 14 - bitString.length();
148 String extraZeros = new String ();
149 for (int i = 0; i < nbExtraZeros; i++)
150 extraZeros = extraZeros.concat("0");
151
152 clockString = extraZeros.concat(bitString);
153 }
154
155 byte[] clock_bits = clockString.getBytes();
156 byte[] clock_seq_low = new byte[8];
157 for (int i = 0; i < 8; i++)
158 clock_seq_low[i] = clock_bits[clock_bits.length - i - 1];
159
160 byte[] clock_seq_hi_and_reserved = new byte[8];
162 for (int i = 0; i < 6; i++)
163 clock_seq_hi_and_reserved[i] = clock_bits[clock_bits.length - 8 - i - 1];
164
165 clock_seq_hi_and_reserved[6] = ((new String ("0")).getBytes())[0];
166 clock_seq_hi_and_reserved[7] = ((new String ("1")).getBytes())[0];
167
168 String timeLow = Long.toHexString((new BigInteger (new String (reverseArray(time_low)), 2)).longValue());
169 if (timeLow.length() < 8)
170 {
171 int nbExtraZeros = 8 - timeLow.length();
172 String extraZeros = new String ();
173 for (int i = 0; i < nbExtraZeros; i++)
174 extraZeros = extraZeros.concat("0");
175
176 timeLow = extraZeros.concat(timeLow);
177 }
178
179 String timeMid = Long.toHexString((new BigInteger (new String (reverseArray(time_mid)), 2)).longValue());
180 if (timeMid.length() < 4)
181 {
182 int nbExtraZeros = 4 - timeMid.length();
183 String extraZeros = new String ();
184 for (int i = 0; i < nbExtraZeros; i++)
185 extraZeros = extraZeros.concat("0");
186 timeMid = extraZeros.concat(timeMid);
187 }
188
189 String timeHiAndVersion = Long.toHexString((new BigInteger (new String (reverseArray(time_hi_and_version)), 2)).longValue());
190 if (timeHiAndVersion.length() < 4)
191 {
192 int nbExtraZeros = 4 - timeHiAndVersion.length();
193 String extraZeros = new String ();
194 for (int i = 0; i < nbExtraZeros; i++)
195 extraZeros = extraZeros.concat("0");
196
197 timeHiAndVersion = extraZeros.concat(timeHiAndVersion);
198 }
199
200 String clockSeqHiAndReserved = Long.toHexString((new BigInteger (new String (reverseArray(clock_seq_hi_and_reserved)), 2)).longValue());
201 if (clockSeqHiAndReserved.length() < 2)
202 {
203 int nbExtraZeros = 2 - clockSeqHiAndReserved.length();
204 String extraZeros = new String ();
205 for (int i = 0; i < nbExtraZeros; i++)
206 extraZeros = extraZeros.concat("0");
207
208 clockSeqHiAndReserved = extraZeros.concat(clockSeqHiAndReserved);
209 }
210
211 String clockSeqLow = Long.toHexString((new BigInteger (new String (reverseArray(clock_seq_low)), 2)).longValue());
212 if (clockSeqLow.length() < 2)
213 {
214 int nbExtraZeros = 2 - clockSeqLow.length();
215 String extraZeros = new String ();
216 for (int i = 0; i < nbExtraZeros; i++)
217 extraZeros = extraZeros.concat("0");
218
219 clockSeqLow = extraZeros.concat(clockSeqLow);
220 }
221
222 Random secureRandom = null;
237 try
238 {
239 secureRandom = SecureRandom.getInstance("SHA1PRNG", "SUN");
240 }
241 catch (Exception e)
242 {
243 secureRandom = new Random ();
244 }
245
246 long nodeValue = secureRandom.nextLong();
247 nodeValue = Math.abs(nodeValue);
248 while (nodeValue > 140737488355328L)
249 {
250 nodeValue = secureRandom.nextLong();
251 nodeValue = Math.abs(nodeValue);
252 }
253
254 BigInteger nodeInt = BigInteger.valueOf(nodeValue);
255 String nodeString = nodeInt.toString(2);
256 if (nodeString.length() < 47)
257 {
258 int nbExtraZeros = 47 - nodeString.length();
259 String extraZeros = new String ();
260 for (int i = 0; i < nbExtraZeros; i++)
261 extraZeros = extraZeros.concat("0");
262
263 nodeString = extraZeros.concat(nodeString);
264 }
265
266 byte[] node_bits = nodeString.getBytes();
267 byte[] node = new byte[48];
268 for (int i = 0; i < 47; i++)
269 node[i] = node_bits[node_bits.length - i - 1];
270
271 node[47] = ((new String ("1")).getBytes())[0];
272 String theNode = Long.toHexString((new BigInteger (new String (reverseArray(node)), 2)).longValue());
273 if (theNode.length() < 12)
274 {
275 int nbExtraZeros = 12 - theNode.length();
276 String extraZeros = new String ();
277 for (int i = 0; i < nbExtraZeros; i++)
278 extraZeros = extraZeros.concat("0");
279 theNode = extraZeros.concat(theNode);
280 }
281
282 String result = timeLow + "-" + timeMid + "-" + timeHiAndVersion + "-" + clockSeqHiAndReserved + clockSeqLow + "-" + theNode;
283
284 return result.toUpperCase();
285 }
286
287 private static byte[] reverseArray(byte[] bits)
288 {
289 byte[] result = new byte[bits.length];
290 for (int i = 0; i < result.length; i++)
291 result[i] = bits[result.length - 1 - i];
292
293 return result;
294 }
295
296 public void destroy()
297 {
298 }
299
300 public void init()
301 {
302 }
303 }
304 |
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