org.apache.camel.support.builder.OutputStreamBuilder 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.support.builder;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import org.apache.camel.Exchange;
import org.apache.camel.converter.stream.CachedOutputStream;
import org.apache.camel.support.ExchangeHelper;
/**
* Utility to hide the complexity of choosing which OutputStream
* implementation to choose.
*
* Itself masquerades as an OutputStream, but really delegates to a
* CachedOutputStream of a ByteArrayOutputStream.
*/
public final class OutputStreamBuilder extends OutputStream {
private final OutputStream outputStream;
private OutputStreamBuilder(final Exchange exchange) {
if (ExchangeHelper.isStreamCachingEnabled(exchange)) {
outputStream = new CachedOutputStream(exchange);
} else {
outputStream = new ByteArrayOutputStream();
}
}
/**
* Creates a new OutputStreamBuilder with the current exchange
*
* Use the {@link #build()} when writing to the stream is finished,
* and you need the result of this operation.
*
* @param exchange the current Exchange
* @return the builder
*/
public static OutputStreamBuilder withExchange(final Exchange exchange) {
return new OutputStreamBuilder(exchange);
}
@Override
public void write(final byte[] b, final int off, final int len) throws IOException {
outputStream.write(b, off, len);
}
@Override
public void write(final byte[] b) throws IOException {
outputStream.write(b);
}
@Override
public void write(final int b) throws IOException {
outputStream.write(b);
}
@Override
public void flush() throws IOException {
outputStream.flush();
}
@Override
public void close() throws IOException {
outputStream.close();
}
/**
* Builds the result of using this builder as either a
* {@link org.apache.camel.converter.stream.CachedOutputStream} if stream caching is enabled,
* otherwise byte[].
*/
public Object build() throws IOException {
if (outputStream instanceof CachedOutputStream) {
return ((CachedOutputStream)outputStream).newStreamCache();
}
return ((ByteArrayOutputStream)outputStream).toByteArray();
}
}