| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you 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 org.apache.johnzon.core; |
| |
| class SimpleStack<T> { |
| |
| private Element<T> head; |
| |
| void push(final T element) { |
| |
| final Element<T> tmp = new Element<T>(); |
| tmp.payload = element; |
| tmp.previous = head; |
| head = tmp; |
| |
| } |
| |
| T pop() { |
| |
| final T tmp = head.payload; |
| head = head.previous; |
| return tmp; |
| |
| } |
| |
| T peek() { |
| return head.payload; |
| } |
| |
| boolean isEmpty() { |
| return head == null; |
| } |
| |
| private static class Element<T> { |
| |
| public Element() { |
| |
| } |
| |
| private Element<T> previous; |
| private T payload; |
| |
| } |
| |
| } |