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; 020 021 import org.apache.camel.Exchange; 022 import org.apache.camel.component.file.FileComponent; 023 import org.apache.camel.component.file.GenericFile; 024 import org.apache.camel.component.file.GenericFileEndpoint; 025 import org.apache.camel.component.file.GenericFileExclusiveReadLockStrategy; 026 import org.apache.camel.component.file.GenericFileOperations; 027 import org.apache.camel.util.FileUtil; 028 import org.slf4j.Logger; 029 import org.slf4j.LoggerFactory; 030 031 /** 032 * Acquires read lock to the given file using a marker file so other Camel consumers wont acquire the same file. 033 * This is the default behavior in Camel 1.x. 034 */ 035 public class MarkerFileExclusiveReadLockStrategy implements GenericFileExclusiveReadLockStrategy<File> { 036 private static final transient Logger LOG = LoggerFactory.getLogger(MarkerFileExclusiveReadLockStrategy.class); 037 038 public void prepareOnStartup(GenericFileOperations<File> operations, GenericFileEndpoint<File> endpoint) { 039 String dir = endpoint.getConfiguration().getDirectory(); 040 File file = new File(dir); 041 042 LOG.debug("Prepare on startup by deleting orphaned lock files from: {}", dir); 043 044 deleteLockFiles(file, endpoint.isRecursive()); 045 } 046 047 public boolean acquireExclusiveReadLock(GenericFileOperations<File> operations, 048 GenericFile<File> file, Exchange exchange) throws Exception { 049 String lockFileName = getLockFileName(file); 050 LOG.trace("Locking the file: {} using the lock file name: {}", file, lockFileName); 051 052 // create a plain file as marker filer for locking (do not use FileLock) 053 boolean acquired = FileUtil.createNewFile(new File(lockFileName)); 054 exchange.setProperty(Exchange.FILE_LOCK_FILE_ACQUIRED, acquired); 055 056 return acquired; 057 } 058 059 public void releaseExclusiveReadLock(GenericFileOperations<File> operations, 060 GenericFile<File> file, Exchange exchange) throws Exception { 061 String lockFileName = getLockFileName(file); 062 File lock = new File(lockFileName); 063 // only release the file if camel get the lock before 064 if (exchange.getProperty(Exchange.FILE_LOCK_FILE_ACQUIRED, false, Boolean.class)) { 065 LOG.trace("Unlocking file: {}", lockFileName); 066 boolean deleted = FileUtil.deleteFile(lock); 067 LOG.trace("Lock file: {} was deleted: {}", lockFileName, deleted); 068 } else { 069 LOG.trace("Don't try to delete the Lock file: {} as camel doesn't get to lock before.", lockFileName); 070 } 071 } 072 073 public void setTimeout(long timeout) { 074 // noop 075 } 076 077 public void setCheckInterval(long checkInterval) { 078 // noop 079 } 080 081 private static void deleteLockFiles(File dir, boolean recursive) { 082 File[] files = dir.listFiles(); 083 if (files == null || files.length == 0) { 084 return; 085 } 086 087 for (File file : files) { 088 if (file.getName().startsWith(".")) { 089 // files starting with dot should be skipped 090 continue; 091 } else if (file.getName().endsWith(FileComponent.DEFAULT_LOCK_FILE_POSTFIX)) { 092 LOG.warn("Deleting orphaned lock file: " + file); 093 FileUtil.deleteFile(file); 094 } else if (recursive && file.isDirectory()) { 095 deleteLockFiles(file, true); 096 } 097 } 098 } 099 100 private static String getLockFileName(GenericFile<File> file) { 101 return file.getAbsoluteFilePath() + FileComponent.DEFAULT_LOCK_FILE_POSTFIX; 102 } 103 104 }