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+// $Id:
+// FORESTER -- software libraries and applications
+// for evolutionary biology research and applications.
+//
+// Copyright (C) 2008-2009 Christian M. Zmasek
+// Copyright (C) 2008-2009 Burnham Institute for Medical Research
+// All rights reserved
+// 
+// This library is free software; you can redistribute it and/or
+// modify it under the terms of the GNU Lesser General Public
+// License as published by the Free Software Foundation; either
+// version 2.1 of the License, or (at your option) any later version.
+//
+// This library 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
+// Lesser General Public License for more details.
+// 
+// You should have received a copy of the GNU Lesser General Public
+// License along with this library; if not, write to the Free Software
+// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
+//
+// Contact: phylosoft @ gmail . com
+// WWW: www.phylosoft.org/forester
+
+package org.forester.datastructures;
+
+import java.util.LinkedList;
+import java.util.NoSuchElementException;
+
+/*
+ * A simple Queue data structure. Created: 10/23/2005 by Christian M. Zmasek.
+ * Last modified: 10/23/2005 by Christian M. Zmasek.
+ * 
+ * @author Christian M. Zmasek
+ * 
+ * @version 1.000
+ */
+public class Queue {
+
+    // Instance variables
+    // ------------------
+    private final LinkedList<Object> _data;
+
+    // Constructor
+    // -----------
+    /**
+     * This created a new, empty Queue object.
+     */
+    public Queue() {
+        _data = new LinkedList<Object>();
+    }
+
+    /**
+     * Removes all elements from this queue.
+     */
+    public void clear() {
+        getData().clear();
+    }
+
+    /**
+     * Dequeues one element from this queue.
+     * 
+     * @return the dequeued object
+     * @throws NoSuchElementException
+     *             if this queue is empty
+     */
+    public Object dequeue() throws NoSuchElementException {
+        if ( isEmpty() ) {
+            throw new NoSuchElementException( "Attempt to dequeue from an empty Queue." );
+        }
+        return getData().removeFirst();
+    }
+
+    // Public methods
+    // --------------
+    /**
+     * Adds Object element to thisqueue.
+     * 
+     * @param element
+     *            the Object to be enqueued
+     */
+    public void enqueue( final Object element ) {
+        getData().add( element );
+    }
+
+    // Private methods
+    // ---------------
+    /**
+     * Returns the LinkedList upon which this queue is based.
+     * 
+     * @return the LinkedList upon which this queue is based
+     */
+    private LinkedList<Object> getData() {
+        return _data;
+    }
+
+    /**
+     * Returns whether or not this queue is empty.
+     * 
+     * @return true if this queue is empty, false otherwise
+     */
+    public boolean isEmpty() {
+        return getData().isEmpty();
+    }
+} // end of class Queue.