/*
* 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.nifi.processors.hadoop.util;
import org.apache.hadoop.io.DataInputBuffer;
import org.apache.hadoop.io.Writable;
import org.apache.nifi.stream.io.BufferedOutputStream;
import org.apache.nifi.stream.io.DataOutputStream;
import java.io.DataInput;
import java.io.DataOutput;
import java.io.IOException;
import java.io.OutputStream;
/**
* This class will write to an output stream, rather than an in-memory buffer, the fields being read.
*
*
*/
public class OutputStreamWritable implements Writable {
private static final int BUFFER_SIZE = 16384;
private final DataOutputStream dos;
private final boolean writeLength;
public OutputStreamWritable(OutputStream out, boolean writeLength) {
this.dos = new DataOutputStream(new BufferedOutputStream(out, BUFFER_SIZE));
this.writeLength = writeLength;
}
@Override
public void write(DataOutput out) throws IOException {
throw new UnsupportedOperationException("OutputStreamWritable does not implement #write");
}
@Override
public void readFields(DataInput in) throws IOException {
if (in instanceof DataInputBuffer) {
byte[] bytes = ((DataInputBuffer) in).getData();
int pos = ((DataInputBuffer) in).getPosition();
int length = ((DataInputBuffer) in).getLength();
int bytesRemaining = length - pos;
if (writeLength) {
dos.write(bytes, pos, bytesRemaining);
} else {
dos.write(bytes, pos + 4, bytesRemaining - 4);
}
in.skipBytes(bytesRemaining);
} else {
int length = in.readInt();
if (writeLength) {
dos.writeInt(length);
}
int numRead = 0;
int toRead = Math.min(BUFFER_SIZE, length);
byte[] buffer = new byte[BUFFER_SIZE];
while (toRead > 0) {
in.readFully(buffer, 0, toRead);
dos.write(buffer, 0, toRead);
numRead += toRead;
toRead = Math.min(BUFFER_SIZE, length - numRead);
}
}
dos.flush();
}
}