/*
* 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.pig;
import java.io.IOException;
import org.apache.pig.classification.InterfaceAudience;
import org.apache.pig.classification.InterfaceStability;
import org.apache.pig.data.Tuple;
/**
* The interface used for the custom mapping of a {@link Tuple} to a byte
* array. The byte array is fed to the stdin of the streaming process.
*
* This interface, together with {@link StreamToPig}, is designed to provide
* a common protocol for data exchange between Pig runtime and streaming
* executables.
*
* Typically, a user implements this interface for a particular type of
* stream command and specifies the implementation class in the Pig DEFINE
* statement.
* @since Pig 0.7
*/
@InterfaceAudience.Public
@InterfaceStability.Stable
public interface PigToStream {
/**
* Given a tuple, produce an array of bytes to be passed to the streaming
* executable.
* @param t Tuple to serialize
* @return Serialized form of the tuple
* @throws IOException
*/
public byte[] serialize(Tuple t) throws IOException;
}