com.sun.enterprise.util.uuid.UuidUtil Maven / Gradle / Ivy
/*
* Copyright (c) 1997, 2018 Oracle and/or its affiliates. All rights reserved.
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v. 2.0, which is available at
* http://www.eclipse.org/legal/epl-2.0.
*
* This Source Code may also be made available under the following Secondary
* Licenses when the conditions for such availability set forth in the
* Eclipse Public License v. 2.0 are satisfied: GNU General Public License,
* version 2 with the GNU Classpath Exception, which is available at
* https://www.gnu.org/software/classpath/license.html.
*
* SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
*/
/*
* UuidUtil.java
*
* Created on October 15, 2002, 9:39 AM
*/
package com.sun.enterprise.util.uuid;
import java.net.InetAddress;
import java.rmi.server.UID;
import java.security.SecureRandom;
/**
* Class UuidUtil
*
*
*/
public class UuidUtil
{
static final String _inetAddr = initInetAddr();
//first method (from MarketMaker Guid)
public static String generateUuidMM() {
return new StringBuffer(new UID().toString()).reverse().append(':').append(_inetAddr).toString();
}
//second method
public static String generateUuid() {
return generateUuid(new Object());
}
//this method can take in the session object
//and insure better uniqueness guarantees
public static String generateUuid(Object obj) {
//low order time bits
long presentTime = System.currentTimeMillis();
int presentTimeLow = (int) presentTime;
String presentTimeStringLow = formatHexString(presentTimeLow);
StringBuilder sb = new StringBuilder(50);
sb.append(presentTimeStringLow);
//sb.append(":");
sb.append(getIdentityHashCode(obj));
//sb.append(":");
//sb.append(_inetAddr);
sb.append(addRandomTo(_inetAddr));
//sb.append(":");
sb.append(getNextRandomString());
return sb.toString();
}
/**
* Method initInetAddr
*
*
* @return
*
* @audience
*/
private static String initInetAddr() {
try {
byte[] bytes = InetAddress.getLocalHost().getAddress();
StringBuilder b = new StringBuilder();
for (int i = 0; i < bytes.length; i++) {
String s = Integer.toHexString(bytes[i]);
if (bytes[i] < 0) {
b.append(s.substring(s.length() - 2));
} else {
b.append(s);
}
}
return b.toString();
} catch (Exception ex) {
//must return a value
return "a48eb993";
//return null;
}
}
private static String addRandomTo(String hexString)
{
long hexAsLong = convertToLong(hexString);
int nextRandom = getNextInt();
long resultInt = hexAsLong + nextRandom;
String result = Long.toHexString(resultInt);
// START PWC 6425338
// Always return a length of 7
int len = result.length();
if (len < 7) {
result = padto7(result);
} else {
result = result.substring(len - 7, len);
}
// END PWC 6425338
return result;
}
/**
* Method getIdentityHashCode
*
*
* @return
*
* @audience
*/
private static String getIdentityHashCode(Object obj) {
try {
int hc = System.identityHashCode(obj);
return formatHexString(hc);
} catch (Exception ex) {
//must return a value
//return null;
return "8AF5182";
}
}
private static String formatHexString(int inputInt)
{
String result;
String s = Integer.toHexString(inputInt);
/* PWC 6425338
if(s.length() < 8)
{
result = s;
} else {
result = s.substring(0, 7);
}
*/
// START PWC 6425338
// Always return a length of 7
int len = s.length();
if (len < 7) {
result = padto7(s);
} else {
result = s.substring(len - 7, len);
}
// END PWC 6425338
return result;
}
private static synchronized int getNextInt() {
return _seeder.nextInt();
}
private static String getNextRandomString() {
int nextInt = getNextInt();
return formatHexString(nextInt);
}
private static long convertToLong(String hexString)
{
long result = 0;
try
{
result = (Long.valueOf(hexString, 16)).longValue();
} catch (NumberFormatException ex) {
}
return result;
}
private static SecureRandom _seeder = new SecureRandom();
/**
* Method main
*
*
* @param args
*
* @audience
*/
public static void main(String[] args) {
System.out.println(UuidUtil.generateUuidMM());
System.out.println(UuidUtil.generateUuid());
System.out.println(UuidUtil.generateUuid(new Object()));
}
// START PWC 6425338
/*
* Pads the given string to a length of 7.
*/
private static String padto7(String s) {
int i = 0;
char[] chars = new char[7];
int len = s.length();
while (i < len) {
chars[i] = s.charAt(i);
i++;
}
while (i < 7) {
chars[i++] = '0';
}
return new String(chars);
}
// END PWC 6425338
}