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.converter.stream;
018    
019    import java.io.File;
020    import java.io.FileInputStream;
021    import java.io.FileNotFoundException;
022    import java.io.IOException;
023    import java.io.InputStream;
024    import java.io.OutputStream;
025    
026    import org.apache.camel.RuntimeCamelException;
027    import org.apache.camel.StreamCache;
028    import org.apache.camel.util.IOHelper;
029    
030    public class FileInputStreamCache extends InputStream implements StreamCache {
031        private InputStream stream;
032        private CachedOutputStream cachedOutputStream;
033        private File file;
034    
035        public FileInputStreamCache(File file, CachedOutputStream cos) throws FileNotFoundException {
036            this.file = file;
037            this.cachedOutputStream = cos;
038            this.stream = new FileInputStream(file);
039        }
040        
041        @Override
042        public void close() {
043            try {
044                getInputStream().close();
045                if (cachedOutputStream != null) {
046                    cachedOutputStream.close();
047                }
048            } catch (Exception e) {
049                throw new RuntimeCamelException(e);
050            } 
051        }
052    
053        @Override
054        public void reset() {
055            try {
056                getInputStream().close();
057                // reset by creating a new stream based on the file
058                stream = new FileInputStream(file);
059            } catch (Exception e) {
060                throw new RuntimeCamelException(e);
061            }            
062        }
063    
064        public void writeTo(OutputStream os) throws IOException {
065            IOHelper.copy(getInputStream(), os);
066        }
067    
068        @Override
069        public int available() throws IOException {
070            return getInputStream().available();
071        }
072    
073        @Override
074        public int read() throws IOException {
075            return getInputStream().read();
076        }
077    
078        protected InputStream getInputStream() {
079            return stream;
080        }
081    
082    }