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.GenericFile;
023    import org.apache.camel.component.file.GenericFileEndpoint;
024    import org.apache.camel.component.file.GenericFileExchange;
025    import org.apache.camel.component.file.GenericFileExclusiveReadLockStrategy;
026    import org.apache.camel.component.file.GenericFileOperations;
027    import org.apache.camel.component.file.GenericFileProcessStrategy;
028    import org.apache.commons.logging.Log;
029    import org.apache.commons.logging.LogFactory;
030    
031    public abstract class GenericFileProcessStrategySupport<T> implements GenericFileProcessStrategy<T> {
032        protected final transient Log log = LogFactory.getLog(getClass());
033        protected GenericFileExclusiveReadLockStrategy<T> exclusiveReadLockStrategy;
034    
035        public boolean begin(GenericFileOperations<T> operations, GenericFileEndpoint<T> endpoint, GenericFileExchange<T> exchange, GenericFile<T> file) throws Exception {
036            // is we use excluse read then acquire the exclusive read (waiting until we got it)
037            if (exclusiveReadLockStrategy != null) {
038                boolean lock = exclusiveReadLockStrategy.acquireExclusiveReadLock(operations, file, exchange);
039                if (!lock) {
040                    // do not begin sice we could not get the exclusive read lcok
041                    return false;
042                }
043            }
044    
045            return true;
046        }
047    
048        public void commit(GenericFileOperations<T> operations, GenericFileEndpoint<T> endpoint, GenericFileExchange<T> exchange, GenericFile<T> file) throws Exception {
049            if (exclusiveReadLockStrategy != null) {
050                exclusiveReadLockStrategy.releaseExclusiveReadLock(operations, file, exchange);
051            }
052    
053            deleteLocalWorkFile(exchange);
054        }
055    
056        public void rollback(GenericFileOperations<T> operations, GenericFileEndpoint<T> endpoint, GenericFileExchange<T> exchange, GenericFile<T> file) throws Exception {
057            if (exclusiveReadLockStrategy != null) {
058                exclusiveReadLockStrategy.releaseExclusiveReadLock(operations, file, exchange);
059            }
060    
061            deleteLocalWorkFile(exchange);
062        }
063    
064        public GenericFileExclusiveReadLockStrategy<T> getExclusiveReadLockStrategy() {
065            return exclusiveReadLockStrategy;
066        }
067    
068        public void setExclusiveReadLockStrategy(GenericFileExclusiveReadLockStrategy<T> exclusiveReadLockStrategy) {
069            this.exclusiveReadLockStrategy = exclusiveReadLockStrategy;
070        }
071    
072        private void deleteLocalWorkFile(GenericFileExchange<T> exchange) {
073            // delete local work file, if it was used (eg by ftp component)
074            File local = exchange.getIn().getHeader(Exchange.FILE_LOCAL_WORK_PATH, File.class);
075            if (local != null && local.exists()) {
076                boolean deleted = local.delete();
077                if (log.isTraceEnabled()) {
078                    log.trace("Local work file: " + local + " was deleted: " + deleted);
079                }
080            }
081        }
082    }
083