/**

  * Free Telco Dictionary

  * Copyright © 2013 František Kučera (frantovo.cz)

  *

  * This program 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, version 3 of the License.

  *

  * 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 General Public License for more details.

  *

  * You should have received a copy of the GNU General Public License

  * along with this program. If not, see <http://www.gnu.org/licenses/>.

  */

 package cz.frantovo.telco.dictionary;

 import java.io.Closeable;

 import java.util.HashSet;

 import java.util.Iterator;

 import java.util.Map;

 import java.util.Map.Entry;

 import java.util.Set;

 import java.util.logging.Level;

 import java.util.logging.Logger;

 import org.w3c.dom.Node;

 import org.w3c.dom.NodeList;

 /**

  * Common functions

  * 

  * @author Ing. František Kučera (frantovo.cz)

  */

 public class Functions {

 	private static final Logger log = Logger.getLogger(Functions.class.getName());

 	public static Iterable<Node> nodeIterable(final NodeList list) {

 		return new Iterable<Node>() {

 			@Override

 			public Iterator<Node> iterator() {

 				return new Iterator<Node>() {

 					int position;

 					@Override

 					public boolean hasNext() {

 						return position < list.getLength();

 					}

 					@Override

 					public Node next() {

 						return list.item(position++);

 					}

 					@Override

 					public void remove() {

 						throw new UnsupportedOperationException("remove not supported");

 					}

 				};

 			}

 		};

 	}

 	public static void close(Closeable c) {

 		try {

 			c.close();

 		} catch (Exception e) {

 			log.log(Level.WARNING, "closing of " + c + " has failed", e);

 		}

 	}

 	public static boolean equalz(Object a, Object b) {

 		return a == null ? b == null : a.equals(b);

 	}

 	public static <K, V> Set<K> getKeysForValue(Map<K, V> map, V value) {

 		Set<K> keysFound = new HashSet<>();

 		for (Entry<K, V> entry : map.entrySet()) {

 			if (equalz(value, entry.getValue())) {

 				keysFound.add(entry.getKey());

 			}

 		}

 		return keysFound;

 	}

 	private Functions() {

 	}

 }