Subscriber.java
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00001 /*
00002  * Software License Agreement (BSD License)
00003  *
00004  *  Copyright (c) 2008, Willow Garage, Inc.
00005  *  All rights reserved.
00006  *
00007  *  Redistribution and use in source and binary forms, with or without
00008  *  modification, are permitted provided that the following conditions
00009  *  are met:
00010  *
00011  *   * Redistributions of source code must retain the above copyright
00012  *     notice, this list of conditions and the following disclaimer.
00013  *   * Redistributions in binary form must reproduce the above
00014  *     copyright notice, this list of conditions and the following
00015  *     disclaimer in the documentation and/or other materials provided
00016  *     with the distribution.
00017  *   * Neither the name of Willow Garage, Inc. nor the names of its
00018  *     contributors may be used to endorse or promote products derived
00019  *     from this software without specific prior written permission.
00020  *
00021  *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
00022  *  "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
00023  *  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
00024  *  FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
00025  *  COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
00026  *  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
00027  *  BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
00028  *  LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
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00031  *  ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
00032  *  POSSIBILITY OF SUCH DAMAGE.
00033  */
00034 
00035 // author: Jason Wolfe
00036 
00037 
00038 
00039 package ros;
00040 
00041 import java.util.Queue;
00042 import java.util.concurrent.ConcurrentLinkedQueue;
00043 
00044 import ros.communication.Message;
00045 
00046 public interface Subscriber<M extends Message> {
00047         public String getTopic();
00048         public void shutdown();
00049         public boolean isValid();
00050         
00051         public static interface Callback<M extends Message> {
00052                 // request must be treated as constant, since it may be concurrently accessed by other threads..
00053                 public void call(M request);
00054         }
00055         
00056         public static class QueueingCallback<M extends Message> implements Callback<M> {
00057                 private Queue<M> queue;
00058                 
00059                 public QueueingCallback() {
00060                         queue = new ConcurrentLinkedQueue<M>();
00061                 }
00062                 
00063                 @SuppressWarnings({ "unchecked"})
00064                 public void call(M request) {
00065                         synchronized(queue) {
00066                                 queue.add((M) request.clone());
00067                                 queue.notify();
00068                         }
00069                 }
00070                 
00071                 public M pop() throws InterruptedException {
00072                         synchronized(queue) {
00073                                 while(queue.isEmpty()) {
00074                                         queue.wait();
00075                                 }
00076                                 return queue.remove();
00077                         }
00078                 }
00079                 
00080 
00081                 public M peek() throws InterruptedException {
00082                         synchronized(queue) {
00083                                 while(queue.isEmpty()) {
00084                                         queue.wait();
00085                                 }
00086                                 return queue.peek();
00087                         }
00088                 }
00089 
00090                 public void clear() {
00091                         synchronized(queue) {
00092                                 queue.clear();
00093                         }
00094                 }
00095 
00096                 
00097                 public boolean isEmpty() {
00098                         return queue.isEmpty();
00099                 }
00100                 
00101                 public int     size() {
00102                         return queue.size();
00103                 }
00104                 
00105         }
00106 }


rosjava_jni
Author(s): Jason Wolfe (jawolfe@willowgarage.com), Nicholas Butko (nbutko@cogsci.ucsd.edu), Lorenz Moesenlechner (moesenle@in.tum.de)
autogenerated on Thu Jan 2 2014 11:07:00