org.apache.camel.converter.stream.StreamCacheConverter Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.camel.converter.stream;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.Reader;
import java.nio.ByteBuffer;
import org.apache.camel.Converter;
import org.apache.camel.Exchange;
import org.apache.camel.StreamCache;
import org.apache.camel.util.IOHelper;
/**
* A set of {@link Converter} methods for wrapping stream-based messages in a {@link StreamCache} implementation to
* ensure message re-readability (eg multicasting, retrying)
*/
@Converter(generateBulkLoader = true)
public final class StreamCacheConverter {
/**
* Utility classes should not have a public constructor.
*/
private StreamCacheConverter() {
}
@Converter(order = 1)
public static StreamCache convertToStreamCache(ByteArrayInputStream stream, Exchange exchange) throws IOException {
return new ByteArrayInputStreamCache(stream);
}
@Converter(order = 2)
public static StreamCache convertToStreamCache(InputStream stream, Exchange exchange) throws IOException {
// transfer the input stream to a cached output stream, and then creates a new stream cache view
// of the data, which ensures the input stream is cached and re-readable.
CachedOutputStream cos = new CachedOutputStream(exchange);
IOHelper.copyAndCloseInput(stream, cos);
return cos.newStreamCache();
}
@Converter(order = 3)
public static StreamCache convertToStreamCache(CachedOutputStream cos, Exchange exchange) throws IOException {
return cos.newStreamCache();
}
@Converter(order = 4)
public static StreamCache convertToStreamCache(Reader reader, Exchange exchange) throws IOException {
String data = exchange.getContext().getTypeConverter().convertTo(String.class, exchange, reader);
return new ReaderCache(data);
}
@Converter(order = 5)
public static byte[] convertToByteArray(StreamCache cache, Exchange exchange) throws IOException {
// lets serialize it as a byte array
ByteArrayOutputStream os = new ByteArrayOutputStream();
cache.writeTo(os);
return os.toByteArray();
}
@Converter(order = 6)
public static ByteBuffer convertToByteBuffer(StreamCache cache, Exchange exchange) throws IOException {
byte[] array = convertToByteArray(cache, exchange);
return ByteBuffer.wrap(array);
}
}