/*
* RapidMiner
*
* Copyright (C) 2001-2008 by Rapid-I and the contributors
*
* Complete list of developers available at our web site:
*
* http://rapid-i.com
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program 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 Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see http://www.gnu.org/licenses/.
*/
package com.rapidminer.example.set;
import java.util.Iterator;
import com.rapidminer.example.Example;
/**
* Returns only a subset of an example set specified by an instance of
* {@link Partition}.
*
* @author Simon Fischer, Ingo Mierswa
* @version $Id: SplittedExampleSetReader.java,v 2.9 2006/03/21 15:35:39
* ingomierswa Exp $
*/
public class SplittedExampleSetReader extends AbstractExampleReader {
/** The underlying reader. */
private Iterator<Example> reader;
/** Index of the current example. */
private int current;
/** The partition. */
private Partition partition;
/** The next example that will be returned. */
private Example next;
public SplittedExampleSetReader(Iterator<Example> reader, Partition partition) {
this.reader = reader;
this.partition = partition;
current = -1;
hasNext();
}
public boolean hasNext() {
while (next == null) {
current++;
if (!partition.hasNext(current))
return false;
Example example = reader.next();
if (example == null)
return false;
if (current >= partition.getTotalSize())
return false;
if (partition.isSelected(current))
next = example;
}
return true;
}
public Example next() {
if (!hasNext()) {
return null;
} else {
Example dummy = next;
next = null;
return dummy;
}
}
}