EDIT

/**

* Copyright (C) 2009 EDIT

* European Distributed Institute of Taxonomy

* http://www.e-taxonomy.eu

*

* The contents of this file are subject to the Mozilla Public License Version 1.1

* See LICENSE.TXT at the top of this package for the full license terms.

*/

package eu.etaxonomy.cdm.io.stream;

import java.util.Set;

import org.apache.logging.log4j.LogManager;import org.apache.logging.log4j.Logger;

import eu.etaxonomy.cdm.io.common.events.IIoObserver;

import eu.etaxonomy.cdm.io.stream.terms.TermUri;

/**

 * FilteredReader filters a stream. Only a sub-stream of the input items

 * is in the output stream.

 * @author a.mueller

 * @since 23.11.2011

 *

 */

public class FilteredStream implements IItemStream {

	@SuppressWarnings("unused")

	private static Logger logger = LogManager.getLogger(FilteredStream.class);

	private final IItemStream reader;

	private final ItemFilter<StreamItem> filter;

	private StreamItem next;

	/**

	 * @param list

	 */

	public FilteredStream(IItemStream reader, ItemFilter<StreamItem> filter) {

		this.reader = reader;

		this.filter = filter;

	}

	@Override

	public StreamItem read() {

	    StreamItem result;

	    if (hasNext()){

		    result = next;

		    next = null;

		}else{

		    result = null;

		}

	    return result;

	}

	@Override

	public boolean hasNext(){

	    if (next != null){

	        return true;

	    }

		while (reader.hasNext()){

		    next = reader.read();

		    if (filter == null || ! filter.toBeRemovedFromStream(next)){

		        return true;

		    }

		}

		next = null;

	    return false;

	}

    @Override

    public TermUri getTerm() {

        return reader.getTerm();

    }

    @Override

    public String getItemLocation() {

        return reader.getItemLocation();

    }

    @Override

    public String getStreamLocation() {

        return reader.getStreamLocation();

    }

    @Override

    public void addObservers(Set<IIoObserver> observers) {

        reader.addObservers(observers);

    }

}