/* * Title: CloudSim Toolkit * Description: CloudSim (Cloud Simulation) Toolkit for Modeling and Simulation of Clouds * Licence: GPL - http://www.gnu.org/copyleft/gpl.html * * Copyright (c) 2009-2010, The University of Melbourne, Australia */package org.cloudbus.cloudsim.core;import java.util.Iterator;import java.util.LinkedList;import java.util.List;import java.util.ListIterator;/** * 這個類是defer隊列,使用linkedlist結構,元素按事件發生時間排序 * 方法: * 添加事件 * 返回迭代器 * 返回大小 * 清除隊列 * This class implements the deferred event queue used by {@link Simulation}. * The event queue uses a linked list to store the events. * * @authorMarcos Dias de Assuncao * @sinceCloudSim Toolkit 1.0 * * @seeSimulation * @seeSimEvent */public class DeferredQueue {/** The list. */private final List<SimEvent> list = new LinkedList<SimEvent>();/** * The max time. * 事件發生的最晚時間 * */private double maxTime = -1;/** * 事件排入佇列時,維護元素的順序,按事件發生事件順序加入 * Adds a new event to the queue. Adding a new event to the queue * preserves the temporal order of the events. * @param newEvent The event to be added to the queue. */public void addEvent(SimEvent newEvent) {// The event has to be inserted as the last of all events// with the same event_time(). Yes, this matters.//返回時間必鬚髮生的時間double eventTime = newEvent.eventTime();if (eventTime >= maxTime) {list.add(newEvent);maxTime = eventTime;return;}ListIterator<SimEvent> iterator = list.listIterator();SimEvent event;//從第一個元素開始搜尋while (iterator.hasNext()) {event = iterator.next();if (event.eventTime() > eventTime) {iterator.previous();iterator.add(newEvent);return;}}//隊列為空白 list.add(newEvent);}/** * Returns an iterator to the events in the queue. * * @return the iterator */public Iterator<SimEvent> iterator() {return list.iterator();}/** * Returns the size of this event queue. * * @return the number of events in the queue. */public int size() {return list.size();}/** * Clears the queue. */public void clear(){list.clear();}}