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 */ 017package org.apache.camel.impl; 018 019import java.net.ServerSocket; 020import java.util.concurrent.atomic.AtomicLong; 021 022import org.apache.camel.spi.UuidGenerator; 023import org.apache.camel.util.IOHelper; 024import org.apache.camel.util.InetAddressUtil; 025import org.apache.camel.util.ObjectHelper; 026import org.slf4j.Logger; 027import org.slf4j.LoggerFactory; 028 029/** 030 * {@link org.apache.camel.spi.UuidGenerator} which is a fast implementation based on 031 * how <a href="http://activemq.apache.org/">Apache ActiveMQ</a> generates its UUID. 032 * <p/> 033 * This implementation is not synchronized but it leverages API which may not be accessible 034 * in the cloud (such as Google App Engine). 035 * <p/> 036 * The JVM system property {@link #PROPERTY_IDGENERATOR_PORT} can be used to set a specific port 037 * number to be used as part of the initialization process to generate unique UUID. 038 */ 039public class ActiveMQUuidGenerator implements UuidGenerator { 040 041 // use same JVM property name as ActiveMQ 042 public static final String PROPERTY_IDGENERATOR_HOSTNAME = "activemq.idgenerator.hostname"; 043 public static final String PROPERTY_IDGENERATOR_LOCALPORT = "activemq.idgenerator.localport"; 044 public static final String PROPERTY_IDGENERATOR_PORT = "activemq.idgenerator.port"; 045 046 private static final Logger LOG = LoggerFactory.getLogger(ActiveMQUuidGenerator.class); 047 private static final String UNIQUE_STUB; 048 private static int instanceCount; 049 private static String hostName; 050 private String seed; 051 private final AtomicLong sequence = new AtomicLong(1); 052 private final int length; 053 054 static { 055 String stub = ""; 056 boolean canAccessSystemProps = true; 057 try { 058 SecurityManager sm = System.getSecurityManager(); 059 if (sm != null) { 060 sm.checkPropertiesAccess(); 061 } 062 } catch (SecurityException se) { 063 canAccessSystemProps = false; 064 } 065 066 if (canAccessSystemProps) { 067 hostName = System.getProperty(PROPERTY_IDGENERATOR_HOSTNAME); 068 int localPort = Integer.parseInt(System.getProperty(PROPERTY_IDGENERATOR_LOCALPORT, "0")); 069 070 int idGeneratorPort = 0; 071 ServerSocket ss = null; 072 try { 073 if (hostName == null) { 074 hostName = InetAddressUtil.getLocalHostName(); 075 } 076 if (localPort == 0) { 077 idGeneratorPort = Integer.parseInt(System.getProperty(PROPERTY_IDGENERATOR_PORT, "0")); 078 LOG.trace("Using port {}", idGeneratorPort); 079 ss = new ServerSocket(idGeneratorPort); 080 localPort = ss.getLocalPort(); 081 stub = "-" + localPort + "-" + System.currentTimeMillis() + "-"; 082 Thread.sleep(100); 083 } else { 084 stub = "-" + localPort + "-" + System.currentTimeMillis() + "-"; 085 } 086 } catch (Exception e) { 087 if (LOG.isTraceEnabled()) { 088 LOG.trace("Cannot generate unique stub by using DNS and binding to local port: " + idGeneratorPort, e); 089 } else { 090 LOG.warn("Cannot generate unique stub by using DNS and binding to local port: " + idGeneratorPort + " due " + e.getMessage()); 091 } 092 // Restore interrupted state so higher level code can deal with it. 093 if (e instanceof InterruptedException) { 094 Thread.currentThread().interrupt(); 095 } 096 } finally { 097 IOHelper.close(ss); 098 } 099 } 100 101 // fallback to use localhost 102 if (hostName == null) { 103 hostName = "localhost"; 104 } 105 hostName = sanitizeHostName(hostName); 106 107 if (ObjectHelper.isEmpty(stub)) { 108 stub = "-1-" + System.currentTimeMillis() + "-"; 109 } 110 UNIQUE_STUB = stub; 111 } 112 113 public ActiveMQUuidGenerator(String prefix) { 114 synchronized (UNIQUE_STUB) { 115 this.seed = prefix + UNIQUE_STUB + (instanceCount++) + "-"; 116 // let the ID be friendly for URL and file systems 117 this.seed = generateSanitizedId(this.seed); 118 this.length = seed.length() + ("" + Long.MAX_VALUE).length(); 119 } 120 } 121 122 public ActiveMQUuidGenerator() { 123 this("ID-" + hostName); 124 } 125 126 /** 127 * As we have to find the hostname as a side-affect of generating a unique 128 * stub, we allow it's easy retrieval here 129 * 130 * @return the local host name 131 */ 132 public static String getHostName() { 133 return hostName; 134 } 135 136 public static String sanitizeHostName(String hostName) { 137 boolean changed = false; 138 139 StringBuilder sb = new StringBuilder(); 140 for (char ch : hostName.toCharArray()) { 141 // only include ASCII chars 142 if (ch < 127) { 143 sb.append(ch); 144 } else { 145 changed = true; 146 } 147 } 148 149 if (changed) { 150 String newHost = sb.toString(); 151 LOG.info("Sanitized hostname from: {} to: {}", hostName, newHost); 152 return newHost; 153 } else { 154 return hostName; 155 } 156 } 157 158 public String generateUuid() { 159 StringBuilder sb = new StringBuilder(length); 160 sb.append(seed); 161 sb.append(sequence.getAndIncrement()); 162 return sb.toString(); 163 } 164 165 /** 166 * Generate a unique ID - that is friendly for a URL or file system 167 * 168 * @return a unique id 169 */ 170 public String generateSanitizedId() { 171 return generateSanitizedId(generateUuid()); 172 } 173 174 /** 175 * Ensures that the id is friendly for a URL or file system 176 * 177 * @param id the unique id 178 * @return the id as file friendly id 179 */ 180 public static String generateSanitizedId(String id) { 181 id = id.replace(':', '-'); 182 id = id.replace('_', '-'); 183 id = id.replace('.', '-'); 184 id = id.replace('/', '-'); 185 return id; 186 } 187}