001 /** 002 * Licensed to the Apache Software Foundation (ASF) under one or more 003 * contributor license agreements. See the NOTICE file distributed with 004 * this work for additional information regarding copyright ownership. 005 * The ASF licenses this file to You under the Apache License, Version 2.0 006 * (the "License"); you may not use this file except in compliance with 007 * the License. You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the License for the specific language governing permissions and 015 * limitations under the License. 016 */ 017 package org.apache.camel.util; 018 019 import java.net.InetAddress; 020 import java.net.ServerSocket; 021 import java.util.logging.Level; 022 023 import org.apache.commons.logging.Log; 024 import org.apache.commons.logging.LogFactory; 025 026 /** 027 * Generator for Globally unique Strings. 028 */ 029 public class UuidGenerator { 030 031 private static final transient Log LOG = LogFactory.getLog(UuidGenerator.class); 032 private static final String UNIQUE_STUB; 033 private static int instanceCount; 034 private static String hostName; 035 private String seed; 036 private long sequence; 037 038 static { 039 String stub = ""; 040 boolean canAccessSystemProps = true; 041 try { 042 SecurityManager sm = System.getSecurityManager(); 043 if (sm != null) { 044 sm.checkPropertiesAccess(); 045 } 046 } catch (SecurityException se) { 047 canAccessSystemProps = false; 048 } 049 050 if (canAccessSystemProps) { 051 try { 052 hostName = InetAddress.getLocalHost().getHostName(); 053 ServerSocket ss = new ServerSocket(0); 054 stub = "/" + ss.getLocalPort() + "-" + System.currentTimeMillis() + "/"; 055 Thread.sleep(100); 056 ss.close(); 057 } catch (Exception ioe) { 058 LOG.warn("Could not generate unique stub", ioe); 059 } 060 } else { 061 hostName = "localhost"; 062 stub = "-1-" + System.currentTimeMillis() + "-"; 063 } 064 UNIQUE_STUB = stub; 065 } 066 067 public UuidGenerator(String prefix) { 068 synchronized (UNIQUE_STUB) { 069 this.seed = prefix + UNIQUE_STUB + (instanceCount++) + "-"; 070 } 071 } 072 073 public UuidGenerator() { 074 this("ID-" + hostName); 075 } 076 077 /** 078 * As we have to find the hostname as a side-affect of generating a unique 079 * stub, we allow it's easy retrevial here 080 * 081 * @return the local host name 082 */ 083 public static String getHostName() { 084 return hostName; 085 } 086 087 /** 088 * Generate a unqiue id 089 */ 090 public synchronized String generateId() { 091 return this.seed + (this.sequence++); 092 } 093 094 /** 095 * Generate a unique ID - that is friendly for a URL or file system 096 * 097 * @return a unique id 098 */ 099 public String generateSanitizedId() { 100 return generateSanitizedId(generateId()); 101 } 102 103 /** 104 * Ensures that the id is friendly for a URL or file system 105 * 106 * @param id the unique id 107 * @return the id as file friendly id 108 */ 109 public static String generateSanitizedId(String id) { 110 id = id.replace(':', '-'); 111 id = id.replace('_', '-'); 112 id = id.replace('.', '-'); 113 return id; 114 } 115 116 }