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.IOException; 020 import java.io.InputStream; 021 import java.io.Reader; 022 import java.io.StringReader; 023 024 import javax.xml.transform.TransformerException; 025 import javax.xml.transform.sax.SAXSource; 026 import javax.xml.transform.stream.StreamSource; 027 028 import org.apache.camel.Converter; 029 import org.apache.camel.Exchange; 030 import org.apache.camel.converter.IOConverter; 031 import org.apache.camel.converter.jaxp.BytesSource; 032 import org.apache.camel.converter.jaxp.StringSource; 033 import org.apache.camel.converter.jaxp.XmlConverter; 034 import org.apache.camel.util.IOHelper; 035 import org.apache.commons.logging.Log; 036 import org.apache.commons.logging.LogFactory; 037 038 /** 039 * A set of {@link Converter} methods for wrapping stream-based messages in a {@link StreamCache} 040 * implementation to ensure message re-readability (eg multicasting, retrying) 041 */ 042 @Converter 043 public class StreamCacheConverter { 044 private static final transient Log LOG = LogFactory.getLog(StreamCacheConverter.class); 045 046 private XmlConverter converter = new XmlConverter(); 047 048 @Converter 049 public StreamCache convertToStreamCache(StreamSource source, Exchange exchange) throws IOException { 050 return new StreamSourceCache(source, exchange); 051 } 052 053 @Converter 054 public StreamCache convertToStreamCache(StringSource source) { 055 //no need to do stream caching for a StringSource 056 return null; 057 } 058 059 @Converter 060 public StreamCache convertToStreamCache(BytesSource source) { 061 //no need to do stream caching for a BytesSource 062 return null; 063 } 064 065 @Converter 066 public StreamCache convertToStreamCache(SAXSource source) throws TransformerException { 067 return new SourceCache(converter.toString(source)); 068 } 069 070 @Converter 071 public StreamCache convertToStreamCache(InputStream stream, Exchange exchange) throws IOException { 072 // set up CachedOutputStream with the properties 073 CachedOutputStream cos = new CachedOutputStream(exchange.getContext().getProperties()); 074 IOHelper.copyAndCloseInput(stream, cos); 075 return cos.getStreamCache(); 076 } 077 078 @Converter 079 public StreamCache convertToStreamCache(Reader reader) throws IOException { 080 return new ReaderCache(IOConverter.toString(reader)); 081 } 082 083 /* 084 * {@link StreamCache} implementation for {@link Source}s 085 */ 086 private class SourceCache extends StringSource implements StreamCache { 087 088 private static final long serialVersionUID = 4147248494104812945L; 089 090 public SourceCache() { 091 } 092 093 public SourceCache(String text) { 094 super(text); 095 } 096 097 public void reset() { 098 // do nothing here 099 } 100 101 } 102 103 /* 104 * {@link StreamCache} implementation for Cache the StreamSource {@link StreamSource}s 105 */ 106 private class StreamSourceCache extends StreamSource implements StreamCache { 107 StreamCache streamCache; 108 ReaderCache readCache; 109 110 public StreamSourceCache(StreamSource source, Exchange exchange) throws IOException { 111 if (source.getInputStream() != null) { 112 // set up CachedOutputStream with the properties 113 CachedOutputStream cos = new CachedOutputStream(exchange.getContext().getProperties()); 114 IOHelper.copyAndCloseInput(source.getInputStream(), cos); 115 streamCache = cos.getStreamCache(); 116 setInputStream((InputStream)streamCache); 117 setSystemId(source.getSystemId()); 118 } 119 if (source.getReader() != null) { 120 readCache = new ReaderCache(IOConverter.toString(source.getReader())); 121 setReader(readCache); 122 } 123 } 124 public void reset() { 125 if (streamCache != null) { 126 streamCache.reset(); 127 } 128 if (readCache != null) { 129 readCache.reset(); 130 } 131 } 132 133 } 134 135 private class ReaderCache extends StringReader implements StreamCache { 136 137 public ReaderCache(String s) { 138 super(s); 139 } 140 141 public void reset() { 142 try { 143 super.reset(); 144 } catch (IOException e) { 145 LOG.warn("Exception is thrown when resets the ReaderCache", e); 146 } 147 } 148 149 public void close() { 150 // Do not release the string for caching 151 } 152 153 } 154 155 156 157 158 }