/*
VisAD system for interactive analysis and visualization of numerical
data. Copyright (C) 1996 - 2017 Bill Hibbard, Curtis Rueden, Tom
Rink, Dave Glowacki, Steve Emmerson, Tom Whittaker, Don Murray, and
Tommy Jasmin.
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public
License as published by the Free Software Foundation; either
version 2 of the License, or (at your option) any later version.
This library 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
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with this library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
MA 02111-1307, USA
$Id: Consolidator.java,v 1.12 2009-03-02 23:35:48 curtis Exp $
*/
package visad.data.in;
import java.rmi.RemoteException;
import java.util.*;
import visad.*;
/**
* Consolidates VisAD data objects together. In general, an instance of this
* class will be the final module in a data-import pipe.
*
* @author Steven R. Emmerson
*/
public final class Consolidator
extends DataInputFilter
{
/**
* Constructs with a particular upstream data source.
*
* @param source The upstream data source. May not be
* <code>null</code>.
* @throws VisADException The upstream data source is <code>null</code>.
*/
public Consolidator(DataInputStream source)
throws VisADException
{
super(source);
}
/**
* Returns the next VisAD data object in the input stream. Returns
* <code>null</code> if there is no next object.
*
* @return A VisAD data object or <code>null</code> if
* there are no more such objects.
* @throws VisADException VisAD failure.
* @throws RemoteException Java RMI failure.
*/
public synchronized DataImpl readData()
throws VisADException, RemoteException
{
System.gc();
DataInputStream source = getSource();
boolean allReals = true;
DataImpl data;
List datums = new ArrayList();
while ((data = source.readData()) != null)
{
allReals &= data instanceof Real;
datums.add(data);
}
int count = datums.size();
if (count == 0)
{
data = null;
}
else if (count == 1)
{
data = (DataImpl)datums.get(0);
}
else
{
data =
allReals
? (DataImpl)
new RealTuple((Real[])datums.toArray(new Real[0]))
: new Tuple(
(DataImpl[])datums.toArray(new DataImpl[0]),
/*copy=*/false);
}
return data;
}
}