146 lines
4.1 KiB
Java
146 lines
4.1 KiB
Java
//******************************************************************************
|
|
//
|
|
// File: CombinerConfig.java
|
|
// Package: edu.rit.pjmr
|
|
// Unit: Class edu.rit.pjmr.CombinerConfig
|
|
//
|
|
// This Java source file is copyright (C) 2013 by Alan Kaminsky. All rights
|
|
// reserved. For further information, contact the author, Alan Kaminsky, at
|
|
// ark@cs.rit.edu.
|
|
//
|
|
// This Java source file is part of the Parallel Java 2 Library ("PJ2"). PJ2 is
|
|
// free software; you can redistribute it and/or modify it under the terms of
|
|
// the GNU General Public License as published by the Free Software Foundation;
|
|
// either version 3 of the License, or (at your option) any later version.
|
|
//
|
|
// PJ2 is distributed in the hope that it will be useful, but WITHOUT ANY
|
|
// WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
|
|
// A PARTICULAR PURPOSE. See the GNU General Public License for more details.
|
|
//
|
|
// A copy of the GNU General Public License is provided in the file gpl.txt. You
|
|
// may also obtain a copy of the GNU General Public License on the World Wide
|
|
// Web at http://www.gnu.org/licenses/gpl.html.
|
|
//
|
|
//******************************************************************************
|
|
|
|
package edu.rit.pjmr;
|
|
|
|
import edu.rit.io.Streamable;
|
|
import edu.rit.io.InStream;
|
|
import edu.rit.io.OutStream;
|
|
import edu.rit.util.Instance;
|
|
import edu.rit.pj2.Vbl;
|
|
import java.io.IOException;
|
|
import java.lang.reflect.InvocationTargetException;
|
|
|
|
/**
|
|
* Class CombinerConfig contains specifications for configuring a {@linkplain
|
|
* Combiner} in a mapper task or reducer task.
|
|
*
|
|
* @param <K> Mapper output key data type.
|
|
* @param <V> Mapper output value data type; must implement interface
|
|
* {@linkplain edu.rit.pj2.Vbl Vbl}.
|
|
*
|
|
* @author Alan Kaminsky
|
|
* @version 10-Dec-2013
|
|
*/
|
|
class CombinerConfig<K,V extends Vbl>
|
|
implements Streamable
|
|
{
|
|
|
|
// Exported data members.
|
|
|
|
// Combiner class name.
|
|
String combinerClassName;
|
|
|
|
// Exported constructors.
|
|
|
|
/**
|
|
* Construct a new uninitialized combiner config object. This constructor is
|
|
* for use only by object deserialization.
|
|
*/
|
|
CombinerConfig()
|
|
{
|
|
}
|
|
|
|
/**
|
|
* Construct a new combiner config object.
|
|
*
|
|
* @param combinerClass Combiner class.
|
|
*
|
|
* @exception NullPointerException
|
|
* (unchecked exception) Thrown if <TT>combinerClass</TT> is null.
|
|
*/
|
|
<T extends Combiner<K,V>> CombinerConfig
|
|
(Class<T> combinerClass)
|
|
{
|
|
if (combinerClass == null)
|
|
throw new NullPointerException
|
|
("CombinerConfig(): combinerClass is null");
|
|
this.combinerClassName = combinerClass.getName();
|
|
}
|
|
|
|
// Exported operations.
|
|
|
|
/**
|
|
* Write this combiner config object to the given out stream.
|
|
*
|
|
* @param out Out stream.
|
|
*
|
|
* @exception IOException
|
|
* Thrown if an I/O error occurred.
|
|
*/
|
|
public void writeOut
|
|
(OutStream out)
|
|
throws IOException
|
|
{
|
|
out.writeString (combinerClassName);
|
|
}
|
|
|
|
/**
|
|
* Read this combiner config object from the given in stream.
|
|
*
|
|
* @param in In stream.
|
|
*
|
|
* @exception IOException
|
|
* Thrown if an I/O error occurred.
|
|
*/
|
|
public void readIn
|
|
(InStream in)
|
|
throws IOException
|
|
{
|
|
combinerClassName = in.readString();
|
|
}
|
|
|
|
// Hidden operations.
|
|
|
|
/**
|
|
* Construct a new combiner as specified by this combiner config object.
|
|
*
|
|
* @return Combiner.
|
|
*
|
|
* @exception ClassNotFoundException
|
|
* Thrown if the combiner class could not be found.
|
|
* @exception NoSuchMethodException
|
|
* Thrown if the combiner class does not have a no-argument constructor.
|
|
* @exception InstantiationException
|
|
* Thrown if the combiner class could not be instantiated.
|
|
* @exception IllegalAccessException
|
|
* Thrown if the combiner class or its no-argument constructor is not
|
|
* accessible.
|
|
* @exception InvocationTargetException
|
|
* Thrown if the combiner class constructor threw an exception.
|
|
*/
|
|
Combiner<K,V> newInstance()
|
|
throws ClassNotFoundException,
|
|
NoSuchMethodException,
|
|
InstantiationException,
|
|
IllegalAccessException,
|
|
InvocationTargetException
|
|
{
|
|
return (Combiner<K,V>)
|
|
Instance.newDefaultInstance (combinerClassName, true);
|
|
}
|
|
|
|
}
|