/interpreter/tags/at2dist130208/src/edu/vub/at/actors/eventloops/FutureEvent.java
Java | 76 lines | 20 code | 7 blank | 49 comment | 0 complexity | e9925ab826684dce069ac90e48e19f11 MD5 | raw file
1/** 2 * AmbientTalk/2 Project 3 * FutureEvent.java created on 27-dec-2006 at 15:50:33 4 * (c) Programming Technology Lab, 2006 - 2007 5 * Authors: Tom Van Cutsem & Stijn Mostinckx 6 * 7 * Permission is hereby granted, free of charge, to any person 8 * obtaining a copy of this software and associated documentation 9 * files (the "Software"), to deal in the Software without 10 * restriction, including without limitation the rights to use, 11 * copy, modify, merge, publish, distribute, sublicense, and/or 12 * sell copies of the Software, and to permit persons to whom the 13 * Software is furnished to do so, subject to the following 14 * conditions: 15 * 16 * The above copyright notice and this permission notice shall be 17 * included in all copies or substantial portions of the Software. 18 * 19 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 20 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES 21 * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 22 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT 23 * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, 24 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 25 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR 26 * OTHER DEALINGS IN THE SOFTWARE. 27 */ 28package edu.vub.at.actors.eventloops; 29 30/** 31 * A Future Event has an associated Future object to which the event 32 * will pass the return value or exception of a certain computation to be 33 * specified by a subclass. 34 * 35 * @author tvcutsem 36 */ 37public abstract class FutureEvent extends Event { 38 39 private final Future future_; 40 41 /** 42 * Verbode constructor which takes a future to be resolved by this event as well as a 43 * descriptive string describing this event for debugging purposes. 44 * @param description a description of the event for debugging purposes. 45 * @param reply the future which will be resolved when this event has been executed. 46 */ 47 public FutureEvent(String description, Future reply) { 48 super(description); 49 future_ = reply; 50 } 51 52 /** 53 * Default constructor which takes a future to be resolved by this event. 54 * @param reply the future which will be resolved when this event has been executed. 55 */ 56 public FutureEvent(Future reply) { 57 future_ = reply; 58 } 59 60 public void process(Object owner) { 61 try { 62 Object result = this.execute(owner); 63 future_.resolve(result); 64 } catch(Exception e) { 65 future_.ruin(e); 66 } 67 } 68 69 /** 70 * Template method to be overwritten by concrete instantiations of this class. This method 71 * is called by the {@link FutureEvent#process(Object)} method and its outcome is used to 72 * resolve or ruin the Future attached to this event. 73 */ 74 public abstract Object execute(Object owner) throws Exception; 75 76}