/*
 *  RapidMiner
 *
 *  Copyright (C) 2001-2014 by RapidMiner and the contributors
 *
 *  Complete list of developers available at our web site:
 *
 *       http://rapidminer.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;

import java.util.Iterator;


/**
 * An iterator for attribute roles which is able to iterate over all
 * attributes or skip either regular or special attributes.
 * 
 * @author Ingo Mierswa
 */
public class AttributeRoleIterator implements Iterator<AttributeRole> {
	
	private Iterator<AttributeRole> parent;
	
	private int type = Attributes.REGULAR;
	
	private AttributeRole current = null;
	
	public AttributeRoleIterator(Iterator<AttributeRole> parent, int type) {
		this.parent = parent;
		this.type = type;
	}
	
	public boolean hasNext() {
        while ((current == null) && (parent.hasNext())) {
           	AttributeRole candidate = parent.next();
            switch (type) {
                case Attributes.REGULAR:
                    if (!candidate.isSpecial())
                        current = candidate;
                    break;
                case Attributes.SPECIAL:
                    if (candidate.isSpecial())
                        current = candidate;
                    break;
                case Attributes.ALL:
                    current = candidate;
                    break;
                default:
                    break;
            }
        }
        return current != null;
	}
    
	public AttributeRole next() {
		hasNext();
		AttributeRole returnValue = current;
		current = null;
		return returnValue;
	}

	public void remove() {
		parent.remove();
		this.current = null;
	}
}