/**
Copyright (C) SYSTAP, LLC DBA Blazegraph 2006-2016. All rights reserved.
Contact:
SYSTAP, LLC DBA Blazegraph
2501 Calvert ST NW #106
Washington, DC 20008
licenses@blazegraph.com
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 2 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, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
/*
* Created on Sep 3, 2011
*/
package com.bigdata.bop.bindingSet;
import java.util.ArrayList;
/**
* A light weight stack. Items are stored in the backing {@link ArrayList}. The
* top of the stack is {@link ArrayList#size()} MINUS ONE (1). The bottom of the
* stack is index ZERO (0).
* <p>
* Note: {@link java.util.Stack} does not offer a constructor which may be used
* to specify the initial capacity.
*
* @author <a href="mailto:thompsonbry@users.sourceforge.net">Bryan Thompson</a>
* @version $Id$
* @param <E>
* The generic type of the elements in the stack.
*/
public class LightStack<E> extends ArrayList<E> {
/**
*
*/
private static final long serialVersionUID = 1L;
public LightStack(int initialCapacity) {
super(initialCapacity);
}
/**
* Push an item onto the stack.
*
* @return That item.
*/
public E push(final E o) {
add(o);
return o;
}
/**
* Remove and return the object at the top of the stack.
*/
public E pop() {
return remove(size() - 1);
}
/**
* Return the object on the top of the stack.
*/
public synchronized E peek() {
return get(size() - 1);
}
}