| /* |
| * 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. |
| */ |
| |
| using System; |
| using System.Threading; |
| using System.Collections.Generic; |
| |
| namespace Apache.NMS.ActiveMQ.Threads |
| { |
| /// <summary> |
| /// Scheduler Service useful for running various delayed units of work. |
| /// </summary> |
| public class Scheduler |
| { |
| private object syncRoot = new object(); |
| private readonly String name; |
| private TimerEx timer; |
| private readonly Dictionary<Object, TimerTask> timerTasks = new Dictionary<object, TimerTask>(); |
| private bool started = false; |
| |
| public Scheduler(String name) |
| { |
| this.name = name; |
| } |
| |
| /// <summary> |
| /// Executes the given task periodically using a fixed-delay execution style |
| /// which prevents tasks from bunching should there be some delay such as |
| /// garbage collection or machine sleep. |
| /// |
| /// This repeating unit of work can later be cancelled using the WaitCallback |
| /// that was originally used to initiate the processing. |
| /// </summary> |
| public void ExecutePeriodically(WaitCallback task, object arg, int period) |
| { |
| lock (this.syncRoot) |
| { |
| CheckStarted(); |
| TimerTask timerTask = timer.Schedule(task, arg, period, period); |
| timerTasks.Add(task, timerTask); |
| } |
| } |
| |
| /// <summary> |
| /// Executes the given task periodically using a fixed-delay execution style |
| /// which prevents tasks from bunching should there be some delay such as |
| /// garbage collection or machine sleep. |
| /// |
| /// This repeating unit of work can later be cancelled using the WaitCallback |
| /// that was originally used to initiate the processing. |
| /// </summary> |
| public void ExecutePeriodically(WaitCallback task, object arg, TimeSpan period) |
| { |
| lock (this.syncRoot) |
| { |
| CheckStarted(); |
| TimerTask timerTask = timer.Schedule(task, arg, period, period); |
| timerTasks.Add(task, timerTask); |
| } |
| } |
| |
| /// <summary> |
| /// Executes the given task the after delay, no reference is kept for this |
| /// task so it cannot be cancelled later. |
| /// </summary> |
| public void ExecuteAfterDelay(WaitCallback task, object arg, int delay) |
| { |
| lock (this.syncRoot) |
| { |
| CheckStarted(); |
| } |
| |
| timer.Schedule(task, arg, delay); |
| } |
| |
| /// <summary> |
| /// Executes the given task the after delay, no reference is kept for this |
| /// task so it cannot be cancelled later. |
| /// </summary> |
| public void ExecuteAfterDelay(WaitCallback task, object arg, TimeSpan delay) |
| { |
| lock (this.syncRoot) |
| { |
| CheckStarted(); |
| } |
| |
| timer.Schedule(task, arg, delay); |
| } |
| |
| public void Cancel(object task) |
| { |
| lock (this.syncRoot) |
| { |
| if (timerTasks.ContainsKey(task)) |
| { |
| TimerTask ticket = timerTasks[task]; |
| if (ticket != null) |
| { |
| ticket.Cancel(); |
| timer.Purge(); // remove cancelled TimerTasks |
| } |
| |
| timerTasks.Remove(task); |
| } |
| } |
| } |
| |
| public void Start() |
| { |
| lock (this.syncRoot) |
| { |
| this.timer = new TimerEx(name, true); |
| this.started = true; |
| } |
| } |
| |
| public void Stop() |
| { |
| lock (this.syncRoot) |
| { |
| this.started = false; |
| if (this.timer != null) |
| { |
| this.timer.Cancel(); |
| } |
| } |
| } |
| |
| public String Name |
| { |
| get { return this.name; } |
| } |
| |
| public bool Started |
| { |
| get |
| { |
| lock (this.syncRoot) |
| { |
| return this.started; |
| } |
| } |
| } |
| |
| public override string ToString() |
| { |
| return string.Format("[Scheduler][{0}]", name); |
| } |
| |
| private void CheckStarted() |
| { |
| if (!this.started) |
| { |
| throw new InvalidOperationException("The Schedular has not been started yet"); |
| } |
| } |
| } |
| } |
| |