From 7c279747beb43c7e88633a6228a155a30e6834f7 Mon Sep 17 00:00:00 2001 From: Benjamin Culkin Date: Mon, 27 May 2024 11:38:33 -0400 Subject: Initial import --- .../foundation/notification/Notification.java | 59 ++++++ .../notification/NotificationCentre.java | 200 +++++++++++++++++++++ 2 files changed, 259 insertions(+) create mode 100644 israfil-foundation-notification/src/main/java/net/israfil/foundation/notification/Notification.java create mode 100644 israfil-foundation-notification/src/main/java/net/israfil/foundation/notification/NotificationCentre.java (limited to 'israfil-foundation-notification/src/main/java/net') diff --git a/israfil-foundation-notification/src/main/java/net/israfil/foundation/notification/Notification.java b/israfil-foundation-notification/src/main/java/net/israfil/foundation/notification/Notification.java new file mode 100644 index 0000000..acf60b8 --- /dev/null +++ b/israfil-foundation-notification/src/main/java/net/israfil/foundation/notification/Notification.java @@ -0,0 +1,59 @@ +/* + * Copyright (c) 2003, 2004, 2005, 2006 Israfil Consulting Services Corporation + * Copyright (c) 2003, 2004, 2005, 2006 Christian Edward Gruber + * All Rights Reserved + * + * This software is licensed under the Berkeley Standard Distribution license, + * (BSD license), as defined below: + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are met: + * + * 1. Redistributions of source code must retain the above copyright notice, this + * list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright notice, + * this list of conditions and the following disclaimer in the documentation + * and/or other materials provided with the distribution. + * 3. Neither the name of Israfil Consulting Services nor the names of its contributors + * may be used to endorse or promote products derived from this software without + * specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED + * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, + * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, + * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, + * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, + * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY + * OF SUCH DAMAGE. + * + * $Id: Notification.java 13 2006-01-27 23:45:36Z cgruber $ + */ +package net.israfil.foundation.notification; + +import java.util.Collections; +import java.util.HashMap; +import java.util.Map; + +/** + * An encapsulated notification, used within a NotificationCentre + * + * @author Christian Edward Gruber + */ +public class Notification { + private static Map EMPTY_INFO = Collections.unmodifiableMap(new HashMap()); + + public final Object sender; + public final String notification; + public final Map info; + public Notification(Object sender, String notification) { + this(sender,notification,EMPTY_INFO); + } + public Notification(Object sender, String notification, Map info) { + this.sender = sender; + this.notification = notification; + this.info = info; + } +} diff --git a/israfil-foundation-notification/src/main/java/net/israfil/foundation/notification/NotificationCentre.java b/israfil-foundation-notification/src/main/java/net/israfil/foundation/notification/NotificationCentre.java new file mode 100644 index 0000000..8261d12 --- /dev/null +++ b/israfil-foundation-notification/src/main/java/net/israfil/foundation/notification/NotificationCentre.java @@ -0,0 +1,200 @@ +/* + * Copyright (c) 2003, 2004, 2005, 2006 Israfil Consulting Services Corporation + * Copyright (c) 2003, 2004, 2005, 2006 Christian Edward Gruber + * All Rights Reserved + * + * This software is licensed under the Berkeley Standard Distribution license, + * (BSD license), as defined below: + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are met: + * + * 1. Redistributions of source code must retain the above copyright notice, this + * list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright notice, + * this list of conditions and the following disclaimer in the documentation + * and/or other materials provided with the distribution. + * 3. Neither the name of Israfil Consulting Services nor the names of its contributors + * may be used to endorse or promote products derived from this software without + * specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED + * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, + * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, + * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, + * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, + * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY + * OF SUCH DAMAGE. + * + * $Id: NotificationCentre.java 125 2006-11-09 15:51:38Z cgruber $ + */ +package net.israfil.foundation.notification; + +import java.util.HashSet; +import java.util.Map; +import java.util.Set; +import java.util.StringTokenizer; + +import net.israfil.foundation.dynamic.DynamicUtil; + +/** + * A nextstep-like central notification system. + * @author cgruber + */ +public class NotificationCentre { + + private static NotificationCentre _shared = new NotificationCentre(); + + private Set observers = new HashSet(); + + protected NotificationCentre() { + } + + public static NotificationCentre defaultCentre() { + return _shared; + } + + /** + * This registers an object as an observer of notifications. The object + * registers interest in either a particular named notification, or a + * particular object who may issue the notifications, or the union of the + * two. The following table lists the possible combinations: + * + * + * + * + * + * + * + * + * + * + * + * + * + * + * + * + * + * + * + * + * + * + * + * + * + * + *
Notification NameSender ObjectEffect
nulla senderNotifications (of any name) from this sender are observed
notification stringnullNotifications with this name (from any sender) are observed.
notification stringa senderOnly notifications with this name and originating from this sender are observed
nullnullAll Notifications from any source will be sent (big performance drag)
+ * @param observer The object instance that wants to be registered + * @param callbackSignature Must be a method that takes a single Object parameter which will be a Notification at run-time, or a single Notification parameter + * @param notification The name of the notification to watch for (if any) + * @param sender The name of the object to whose notifications should be paid attention. (if any) + */ + public void addObserver(Object observer, + String callbackSignature, + String notification, + Object sender){ + if (observer == null) return; + if (callbackSignature == null) + throw new IllegalArgumentException("Reciever did not pass in a callback method."); + if (!checkSignature(observer,callbackSignature)) + throw new IllegalArgumentException("Reciever does not implement specified callback method."); + observers.add(new ObservationSpec(sender,notification, callbackSignature, observer)); + + } + /** Post a notification with the given nam and notifier. */ + public void postNotification(Notification notification) { + for (ObservationSpec obs : this.observers) { + obs.postNotification(notification); + } + } + /** Post a notification with the given name, notifier, and with additional + * context information presented in a java.util.Map. */ + public void postNotification(Object sender,String notification) { + postNotification(new Notification(sender,notification)); + } + /** Post a notification with the given name, notifier, and with additional + * context information presented in a java.util.Map. */ + public void postNotification(Object sender,String notification, Map info) { + postNotification(new Notification(sender,notification,info)); + } + /** Removes an observer from any notofications with either or both a + * provided notification string, or notifier + */ + public void removeObserver(Object observer, String notification, Object sender) { + for (ObservationSpec obs : observers) { + if (obs.observer == observer && + obs.sender == sender && + (obs.notification == null || obs.notification.equals(notification))){ + observers.remove(obs); + } + } + } + public void clearObservers() { + observers.clear(); + } + + private boolean checkSignature(Object receiver,String selector) { + if (!DynamicUtil.respondsTo(receiver,selector)) return false; + StringTokenizer st = new StringTokenizer(selector,":"); + if (st.countTokens() != 2) return false; + st.nextToken(); + String parameter = st.nextToken(); + if (Notification.class.getName().equals(parameter)) return true; + if (Object.class.getName().equals(parameter)) return true; + return false; + } + + /** + * TODO Use WeakReferences + */ + public class ObservationSpec { + public final Object sender; + public final String notification; + public final String callback; + public final Object observer; + private final int _hashCode; + public ObservationSpec(Object sender,String notification,String callback, Object observer) { + if (observer == null) + throw new IllegalArgumentException("Both sender and notification cannot be null"); + this.sender = sender; + this.notification = notification; + this.callback = callback; + this.observer = observer; + + // Pre-calculate hash + int code = 13; + if (sender != null) code *= sender.hashCode(); + if (notification != null) code *= notification.hashCode(); + code *= observer.hashCode(); + this._hashCode = code; + } + public void postNotification(Notification notification) { + if (this.sender == null && this.notification == null) { + _post(notification); + } else if (this.sender == null) { + if (notification.notification.equals(this.notification)) + _post(notification); + } else if (this.notification == null) { + if (notification.sender.equals(this.sender)) + _post(notification); + } else { + if (notification.notification.equals(this.notification) && notification.sender.equals(this.sender)) + _post(notification); + } + } + private void _post(Notification notification) { + DynamicUtil.performOn(this.observer,callback,new Object[]{notification} ); + } + + @Override + public int hashCode() { + return _hashCode; + } + } + +} -- cgit v1.2.3