FetchingIteratorListImpl.java

/*
    This file is part of Cyclos (www.cyclos.org).
    A project of the Social Trade Organisation (www.socialtrade.org).

    Cyclos 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 2 of the License, or
    (at your option) any later version.

    Cyclos 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.

    You should have received a copy of the GNU General Public License
    along with Cyclos; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA

 */
package nl.strohalm.cyclos.utils;

import java.util.Iterator;

import nl.strohalm.cyclos.dao.FetchDAO;
import nl.strohalm.cyclos.entities.Entity;
import nl.strohalm.cyclos.entities.Relationship;

/**
 * Basic implementation for iterator lists, using a delegate iterator
 * @author luis
 */
public class FetchingIteratorListImpl<E> extends IteratorListImpl<E> {

    private FetchDAO       fetchDao;
    private Relationship[] fetch;

    public FetchingIteratorListImpl(final Iterator<E> iterator, final FetchDAO fetchDao, final Relationship... fetch) {
        super(iterator);
        this.fetchDao = fetchDao;
        this.fetch = fetch;
    }

    @Override
    public boolean hasNext() {
        final boolean hasNext = super.hasNext();
        if (!hasNext) {
            // Instantly close the underlying iterator after the last result
            DataIteratorHelper.close(iterator);
        }
        return hasNext;
    }

    @Override
    @SuppressWarnings("unchecked")
    public E next() {
        final E next = super.next();
        return (E) fetchDao.fetch((Entity) next, fetch);
    }

}