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1
5 package org.exoplatform.services.idgenerator.impl;
6
7 import java.io.Serializable  ;
8 import java.net.InetAddress ;
9 import java.security.SecureRandom ;
10 import org.exoplatform.services.idgenerator.IDGeneratorService;
11
16 public class IDGeneratorServiceImpl implements IDGeneratorService {
17 private static String hexServerIP_ = null;
18 private static final SecureRandom seeder_ = new SecureRandom ();
19
20
21 public Serializable generateID(Object o) {
22 return generateStringID(o) ;
23 }
24
25 public long generateLongID(Object o) {
26 throw new RuntimeException ("This operation is not supported") ;
27 }
28
29 public String generateStringID(Object o) {
30 StringBuffer tmpBuffer = new StringBuffer (16);
31 if (hexServerIP_ == null) {
32 InetAddress localInetAddress = null;
33 try {
34 localInetAddress = InetAddress.getLocalHost();
36 }
37 catch (java.net.UnknownHostException uhe) {
38 System.err.println("ContentSetUtil: Could not get the local IP address using InetAddress.getLocalHost()!");
39 uhe.printStackTrace();
41 return null;
42 }
43 byte serverIP[] = localInetAddress.getAddress();
44 hexServerIP_ = hexFormat(getInt(serverIP), 8);
45 }
46 String hashcode = hexFormat(System.identityHashCode(o), 8);
47 tmpBuffer.append(hexServerIP_);
48 tmpBuffer.append(hashcode);
49
50 long timeNow = System.currentTimeMillis();
51 int timeLow = (int)timeNow & 0xFFFFFFFF;
52 int node = seeder_.nextInt();
53
54 StringBuffer guid = new StringBuffer (32);
55 guid.append(hexFormat(timeLow, 8));
56 guid.append(tmpBuffer.toString());
57 guid.append(hexFormat(node, 8));
58 return guid.toString();
59 }
60
61 private static int getInt(byte bytes[]) {
62 int i = 0;
63 int j = 24;
64 for (int k = 0; j >= 0; k++) {
65 int l = bytes[k] & 0xff;
66 i += l << j;
67 j -= 8;
68 }
69 return i;
70 }
71
72 private static String hexFormat(int i, int j) {
73 String s = Integer.toHexString(i);
74 return padHex(s, j) + s;
75 }
76
77 private static String padHex(String s, int i) {
78 StringBuffer tmpBuffer = new StringBuffer ();
79 if (s.length() < i) {
80 for (int j = 0; j < i - s.length(); j++) {
81 tmpBuffer.append('0');
82 }
83 }
84 return tmpBuffer.toString();
85 }
86 } |
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