/**
* Copyright 2013 Netflix, Inc.
*
* Licensed 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 com.netflix.priam.compress;
import org.apache.commons.io.IOUtils;
import org.xerial.snappy.SnappyOutputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.Iterator;
/**
* Byte iterator representing compressed data.
* Uses snappy compression
*/
public class ChunkedStream implements Iterator<byte[]>
{
private boolean hasnext = true;
private ByteArrayOutputStream bos;
private SnappyOutputStream compress;
private InputStream origin;
private long chunkSize;
private static int BYTES_TO_READ = 2048;
public ChunkedStream(InputStream is, long chunkSize) throws IOException
{
this.origin = is;
this.bos = new ByteArrayOutputStream();
this.compress = new SnappyOutputStream(bos);
this.chunkSize = chunkSize;
}
@Override
public boolean hasNext()
{
return hasnext;
}
@Override
public byte[] next()
{
try
{
byte data[] = new byte[BYTES_TO_READ];
int count;
while ((count = origin.read(data, 0, data.length)) != -1)
{
compress.write(data, 0, count);
if (bos.size() >= chunkSize)
return returnSafe();
}
// We don't have anything else to read hence set to false.
return done();
}
catch (IOException e)
{
throw new RuntimeException(e);
}
}
private byte[] done() throws IOException
{
compress.flush();
byte[] return_ = bos.toByteArray();
hasnext = false;
IOUtils.closeQuietly(compress);
IOUtils.closeQuietly(bos);
IOUtils.closeQuietly(origin);
return return_;
}
private byte[] returnSafe() throws IOException
{
byte[] return_ = bos.toByteArray();
bos.reset();
return return_;
}
@Override
public void remove()
{
}
}