/* * Copyright (c) 2014 Hewlett-Packard Development Company, L.P. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or * implied. * See the License for the specific language governing permissions and * limitations under the License. */ package monasca.common.util; import java.util.ArrayList; /** * LIFO Stack semantics around an ArrayList for random access support. Indexed access via * {@link #get(int)} and iteration via {@link #iterator()} is in reverse order (FIFO). Not * threadsafe. */ public class Stack<T> extends ArrayList<T> { private static final long serialVersionUID = 0L; /** * Pushes to the top of the stack. */ public void push(T element) { add(element); } /** * Pops from the top of the stack. */ public T pop() { return remove(size() - 1); } /** * Peeks at the top of the stack. */ public T peek() { return get(size() - 1); } }