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.component.file.strategy; 018 019 import java.io.File; 020 import java.io.RandomAccessFile; 021 import java.nio.channels.Channel; 022 import java.nio.channels.FileChannel; 023 import java.nio.channels.FileLock; 024 025 import org.apache.camel.Exchange; 026 import org.apache.camel.component.file.FileComponent; 027 import org.apache.camel.component.file.GenericFile; 028 import org.apache.camel.component.file.GenericFileExclusiveReadLockStrategy; 029 import org.apache.camel.component.file.GenericFileOperations; 030 import org.apache.camel.util.ExchangeHelper; 031 import org.apache.camel.util.ObjectHelper; 032 import org.apache.commons.logging.Log; 033 import org.apache.commons.logging.LogFactory; 034 035 /** 036 * Acquires read lock to the given file using a marker file so other Camel consumers wont acquire the same file. 037 * This is the default behaviour in Camel 1.x. 038 */ 039 public class MarkerFileExclusiveReadLockStrategy implements GenericFileExclusiveReadLockStrategy<File> { 040 private static final transient Log LOG = LogFactory.getLog(MarkerFileExclusiveReadLockStrategy.class); 041 042 @SuppressWarnings("unchecked") 043 public boolean acquireExclusiveReadLock(GenericFileOperations<File> fileGenericFileOperations, 044 GenericFile<File> file, Exchange exchange) throws Exception { 045 046 String lockFileName = file.getAbsoluteFilePath() + FileComponent.DEFAULT_LOCK_FILE_POSTFIX; 047 if (LOG.isTraceEnabled()) { 048 LOG.trace("Locking the file: " + file + " using the lock file name: " + lockFileName); 049 } 050 051 FileChannel channel = new RandomAccessFile(lockFileName, "rw").getChannel(); 052 FileLock lock = channel.lock(); 053 if (lock != null) { 054 exchange.setProperty("CamelFileLock", lock); 055 exchange.setProperty("CamelFileLockName", lockFileName); 056 return true; 057 } else { 058 return false; 059 } 060 } 061 062 public void releaseExclusiveReadLock(GenericFileOperations<File> fileGenericFileOperations, 063 GenericFile<File> fileGenericFile, Exchange exchange) throws Exception { 064 FileLock lock = ExchangeHelper.getMandatoryProperty(exchange, "CamelFileLock", FileLock.class); 065 String lockFileName = ExchangeHelper.getMandatoryProperty(exchange, "CamelFileLockName", String.class); 066 Channel channel = lock.channel(); 067 068 if (LOG.isTraceEnabled()) { 069 LOG.trace("Unlocking file: " + lockFileName); 070 } 071 try { 072 lock.release(); 073 } finally { 074 // must close channel 075 ObjectHelper.close(channel, "Closing channel", LOG); 076 077 File lockfile = new File(lockFileName); 078 boolean deleted = lockfile.delete(); 079 if (LOG.isTraceEnabled()) { 080 LOG.trace("Lock file: " + lockFileName + " was deleted: " + deleted); 081 } 082 } 083 } 084 085 public void setTimeout(long timeout) { 086 // noop 087 } 088 089 }