From 0ed2c1124cf1b9e49a2ec1fa0126a8df09f9e758 Mon Sep 17 00:00:00 2001 From: Andrew Branson Date: Tue, 7 Oct 2014 09:18:11 +0200 Subject: Repackage to org.cristalise --- .../kernel/entity/proxy/MemberSubscription.java | 141 +++++++++++++++++++++ 1 file changed, 141 insertions(+) create mode 100644 src/main/java/org/cristalise/kernel/entity/proxy/MemberSubscription.java (limited to 'src/main/java/org/cristalise/kernel/entity/proxy/MemberSubscription.java') diff --git a/src/main/java/org/cristalise/kernel/entity/proxy/MemberSubscription.java b/src/main/java/org/cristalise/kernel/entity/proxy/MemberSubscription.java new file mode 100644 index 0000000..2873eb8 --- /dev/null +++ b/src/main/java/org/cristalise/kernel/entity/proxy/MemberSubscription.java @@ -0,0 +1,141 @@ +/** + * This file is part of the CRISTAL-iSE kernel. + * Copyright (c) 2001-2014 The CRISTAL Consortium. All rights reserved. + * + * This library is free software; you can redistribute it and/or modify it + * under the terms of the GNU Lesser General Public License as published + * by the Free Software Foundation; either version 3 of the License, or (at + * your option) any later version. + * + * This library is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; with out even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public + * License for more details. + * + * You should have received a copy of the GNU Lesser General Public License + * along with this library; if not, write to the Free Software Foundation, + * Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. + * + * http://www.fsf.org/licensing/licenses/lgpl.html + */ +package org.cristalise.kernel.entity.proxy; +import java.lang.ref.WeakReference; +import java.util.ArrayList; +import java.util.StringTokenizer; + +import org.cristalise.kernel.common.ObjectNotFoundException; +import org.cristalise.kernel.entity.C2KLocalObject; +import org.cristalise.kernel.utils.Logger; + + +public class MemberSubscription implements Runnable { + public static final String ERROR = "Error"; + public static final String END = "theEND"; + + ItemProxy subject; + String interest; + // keep the subscriber by weak reference, so it is not kept from the garbage collector if no longer used + WeakReference> observerReference; + ArrayList contents = new ArrayList(); + boolean preLoad; + + public MemberSubscription(ProxyObserver observer, String interest, boolean preLoad) { + setObserver(observer); + this.interest = interest; + this.preLoad = preLoad; + } + + @Override + public void run() { + Thread.currentThread().setName("Member Subscription: "+subject.getPath()+":"+interest); + if (preLoad) loadChildren(); + } + + private void loadChildren() { + C newMember; + ProxyObserver observer = getObserver(); + if (observer == null) return; //reaped + try { + // fetch contents of path + String children = subject.queryData(interest+"/all"); + StringTokenizer tok = new StringTokenizer(children, ","); + ArrayList newContents = new ArrayList(); + while (tok.hasMoreTokens()) + newContents.add(tok.nextToken()); + + // look to see what's new + for (String newChild: newContents) { + + // load child object + try { + newMember = (C)subject.getObject(interest+"/"+newChild); + contents.remove(newChild); + observer.add(newMember); + } catch (ObjectNotFoundException ex) { + observer.control(ERROR, "Listed member "+newChild+" was not found."); + } catch (ClassCastException ex) { + Logger.error(ex); + observer.control(ERROR, "Listed member "+newChild+" was the wrong type."); + } + } + // report what's left in old contents as deleted + for (String oldChild: contents) { + observer.remove(interest+"/"+oldChild); + } + //replace contents arraylist + contents = newContents; + //report that we're done + observer.control(END, null); + } catch (Exception ex) { + observer.control(ERROR, "Query on "+interest+" failed with "+ex.getMessage()); + } + } + + public boolean isRelevant(String path) { + Logger.msg(7, "Checking relevance of "+path+" to "+interest); + return (path.startsWith(interest)); + } + + public void update(String path, boolean deleted) { + ProxyObserver observer = getObserver(); + if (observer == null) return; //reaped + Logger.msg(7, "Processing proxy message path "+path +" for "+observer+". Interest: "+interest+" Was Deleted:"+deleted); + if (!path.startsWith(interest)) // doesn't concern us + return; + + if (path.equals(interest)) // refresh contents + loadChildren(); + else { + String name = path.substring(interest.length()); + if (deleted) { + Logger.msg(4, "Removing "+path); + contents.remove(name); + observer.remove(name); + } + else { + try { + C newMember = (C)subject.getObject(path); + Logger.msg(4, "Adding "+path); + contents.add(name); + observer.add(newMember); + } catch (ObjectNotFoundException e) { + Logger.error("Member Subscription: could not load "+path); + Logger.error(e); + } + } + } + } + + public void setObserver(ProxyObserver observer) { + observerReference = new WeakReference>(observer); + } + + public void setSubject(ItemProxy subject) { + this.subject = subject; + } + + public ProxyObserver getObserver() { + return observerReference.get(); + } +} + -- cgit v1.2.3