/*
* JBoss, Home of Professional Open Source
* Copyright 2010, Red Hat Inc., and individual contributors as indicated
* by the @authors tag. See the copyright.txt in the distribution for a
* full listing of individual contributors.
*
* This 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 software 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 software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package org.jboss.as.naming.util;
import java.util.ArrayDeque;
import java.util.Deque;
import java.util.EmptyStackException;
/**
*
* @author Stuart Douglas
*
*/
public class ThreadLocalStack<E> {
private final ThreadLocal<Deque<E>> deque = new ThreadLocal<Deque<E>>();
public void push(E item) {
Deque<E> st = deque.get();
if (st == null) {
st = new ArrayDeque<E>();
deque.set(st);
}
st.push(item);
}
public E peek() {
Deque<E> st = deque.get();
if (st == null) {
return null;
}
return st.peek();
}
public E pop() {
Deque<E> st = deque.get();
if (st == null) {
throw new EmptyStackException();
}
E val = st.pop();
if (st.isEmpty()) {
deque.remove();
}
return val;
}
}