| /** |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You under the Apache License, Version 2.0 |
| * (the "License"); you may not use this file except in compliance with |
| * the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package org.apache.camel.impl; |
| |
| import java.net.ServerSocket; |
| import java.util.concurrent.atomic.AtomicLong; |
| |
| import org.apache.camel.spi.UuidGenerator; |
| import org.apache.camel.util.IOHelper; |
| import org.apache.camel.util.InetAddressUtil; |
| import org.apache.camel.util.ObjectHelper; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| /** |
| * {@link org.apache.camel.spi.UuidGenerator} which is a fast implementation based on |
| * how <a href="http://activemq.apache.org/>Apache ActiveMQ</a> generates its UUID. |
| * <p/> |
| * This implementation is not synchronized but it leverages API which may not be accessible |
| * in the cloud (such as Google App Engine). |
| * <p/> |
| * The JVM system property {@link #PROPERTY_IDGENERATOR_PORT} can be used to set a specific port |
| * number to be used as part of the initialization process to generate unique UUID. |
| */ |
| public class ActiveMQUuidGenerator implements UuidGenerator { |
| |
| // use same JVM property name as ActiveMQ |
| public static final String PROPERTY_IDGENERATOR_PORT = "activemq.idgenerator.port"; |
| private static final transient Logger LOG = LoggerFactory.getLogger(ActiveMQUuidGenerator.class); |
| private static final String UNIQUE_STUB; |
| private static int instanceCount; |
| private static String hostName; |
| private String seed; |
| private final AtomicLong sequence = new AtomicLong(1); |
| private final int length; |
| |
| static { |
| String stub = ""; |
| boolean canAccessSystemProps = true; |
| try { |
| SecurityManager sm = System.getSecurityManager(); |
| if (sm != null) { |
| sm.checkPropertiesAccess(); |
| } |
| } catch (SecurityException se) { |
| canAccessSystemProps = false; |
| } |
| |
| if (canAccessSystemProps) { |
| int idGeneratorPort = 0; |
| ServerSocket ss = null; |
| try { |
| idGeneratorPort = Integer.parseInt(System.getProperty(PROPERTY_IDGENERATOR_PORT, "0")); |
| LOG.trace("Using port {}", idGeneratorPort); |
| hostName = InetAddressUtil.getLocalHostName(); |
| ss = new ServerSocket(idGeneratorPort); |
| stub = "-" + ss.getLocalPort() + "-" + System.currentTimeMillis() + "-"; |
| Thread.sleep(100); |
| ss.close(); |
| } catch (Exception ioe) { |
| if (LOG.isTraceEnabled()) { |
| LOG.trace("Cannot generate unique stub by using DNS and binding to local port: " + idGeneratorPort, ioe); |
| } else { |
| LOG.warn("Cannot generate unique stub by using DNS and binding to local port: " + idGeneratorPort + " due " + ioe.getMessage()); |
| } |
| } finally { |
| IOHelper.close(ss); |
| } |
| } |
| |
| // fallback to use localhost |
| if (hostName == null) { |
| hostName = "localhost"; |
| } |
| |
| if (ObjectHelper.isEmpty(stub)) { |
| stub = "-1-" + System.currentTimeMillis() + "-"; |
| } |
| UNIQUE_STUB = stub; |
| } |
| |
| public ActiveMQUuidGenerator(String prefix) { |
| synchronized (UNIQUE_STUB) { |
| this.seed = prefix + UNIQUE_STUB + (instanceCount++) + "-"; |
| // let the ID be friendly for URL and file systems |
| this.seed = generateSanitizedId(this.seed); |
| this.length = seed.length() + ("" + Long.MAX_VALUE).length(); |
| } |
| } |
| |
| public ActiveMQUuidGenerator() { |
| this("ID-" + hostName); |
| } |
| |
| /** |
| * As we have to find the hostname as a side-affect of generating a unique |
| * stub, we allow it's easy retrieval here |
| * |
| * @return the local host name |
| */ |
| public static String getHostName() { |
| return hostName; |
| } |
| |
| public String generateUuid() { |
| StringBuilder sb = new StringBuilder(length); |
| sb.append(seed); |
| sb.append(sequence.getAndIncrement()); |
| return sb.toString(); |
| } |
| |
| /** |
| * Generate a unique ID - that is friendly for a URL or file system |
| * |
| * @return a unique id |
| */ |
| public String generateSanitizedId() { |
| return generateSanitizedId(generateUuid()); |
| } |
| |
| /** |
| * Ensures that the id is friendly for a URL or file system |
| * |
| * @param id the unique id |
| * @return the id as file friendly id |
| */ |
| public static String generateSanitizedId(String id) { |
| id = id.replace(':', '-'); |
| id = id.replace('_', '-'); |
| id = id.replace('.', '-'); |
| id = id.replace('/', '-'); |
| return id; |
| } |
| } |