001/* Copyright (C) 2013 TU Dortmund 002 * This file is part of AutomataLib, http://www.automatalib.net/. 003 * 004 * AutomataLib is free software; you can redistribute it and/or 005 * modify it under the terms of the GNU Lesser General Public 006 * License version 3.0 as published by the Free Software Foundation. 007 * 008 * AutomataLib is distributed in the hope that it will be useful, 009 * but WITHOUT ANY WARRANTY; without even the implied warranty of 010 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 011 * Lesser General Public License for more details. 012 * 013 * You should have received a copy of the GNU Lesser General Public 014 * License along with AutomataLib; if not, see 015 * http://www.gnu.de/documents/lgpl.en.html. 016 */ 017package net.automatalib.commons.smartcollections; 018 019 020/** 021 * Priority queue interface. Note that this class deliberately does not 022 * specify whether the inserted elements come with their own key (i.e. 023 * implement {@link Comparable} or can be compared using a comparator), 024 * or have external keys attached. 025 * 026 * @author Malte Isberner <malte.isberner@gmail.com> 027 * 028 * @param <E> element class 029 */ 030public interface SmartPriorityQueue<E> extends SmartCollection<E> { 031 032 /** 033 * Retrieves, but does not remove the element with the minimum key 034 * in the priority queue. If there are several elements with minimal key 035 * values, one of them is chosen arbitrarily. 036 * @return an element with a minimal key. 037 */ 038 public abstract E peekMin(); 039 040 /** 041 * Retrieves and remove the element with the minimum key in the priority 042 * queue. If there are several elements with minimal key values, one of 043 * them is chosen arbitrarily. 044 * @return the element with the previously minimal key. 045 */ 046 public abstract E extractMin(); 047 048}