--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/components/visual-panels/core/src/java/vpanels/panel/com/oracle/solaris/vp/panel/common/model/ManagedObjectMonitor.java	Thu May 24 04:16:47 2012 -0400
@@ -0,0 +1,185 @@
+/*
+ * CDDL HEADER START
+ *
+ * The contents of this file are subject to the terms of the
+ * Common Development and Distribution License (the "License").
+ * You may not use this file except in compliance with the License.
+ *
+ * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+ * or http://www.opensolaris.org/os/licensing.
+ * See the License for the specific language governing permissions
+ * and limitations under the License.
+ *
+ * When distributing Covered Code, include this CDDL HEADER in each
+ * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+ * If applicable, add the following below this CDDL HEADER, with the
+ * fields enclosed by brackets "[]" replaced with your own identifying
+ * information: Portions Copyright [yyyy] [name of copyright owner]
+ *
+ * CDDL HEADER END
+ */
+
+/*
+ * Copyright (c) 2009, 2012, Oracle and/or its affiliates. All rights reserved.
+ */
+
+package com.oracle.solaris.vp.panel.common.model;
+
+import java.beans.*;
+import java.util.*;
+import com.oracle.solaris.vp.util.misc.event.*;
+
+/**
+ * An abstract superclass for classes that need the ability to monitor
+ * the existence of and property changes in children of a managed object.
+ * The essential functionality provided by this class is registering
+ * {@code PropertyChangeListener}s with all children, and keeping track of
+ * which children it is listening to so it can property deregister itself
+ * on interval updates (which come too late to reference the managed
+ * object's children list).
+ *
+ * Also includes PropertyChangeEventSource functionality.  This is primarily
+ * a convenience to the classes's two subclasses, so we might ultimately
+ * deem it extravagant and want to pull it out.
+ *
+ * {@code AbstractManagedObject} already listens to all its children for
+ * status and sorting purposes, so another possibility would be to add child
+ * event aggregation to the managed object interface.  The question is
+ * whether we want to force that on all {@code ManagedObject}s.
+ */
+public abstract class ManagedObjectMonitor<T extends ManagedObject>
+    implements IntervalListener, PropertyChangeEventSource
+{
+    protected ManagedObject<T> objects_;
+    protected final List<T> listenees_ = new ArrayList<T>();
+    protected final PropertyChangeListeners pListeners_ =
+	new PropertyChangeListeners();
+
+    private PropertyChangeListener managedObjectListener_ =
+	new PropertyChangeListener() {
+
+	@SuppressWarnings("unchecked")
+	public void propertyChange(PropertyChangeEvent evt) {
+	    Object source = evt.getSource();
+
+	    /*
+	     * Whether this is correct or not depends on whether we
+	     * insist on a convention where managed objects only emit
+	     * PropertyChangeEvents that originate from themselves (or
+	     * managed objects of the same type).
+	     *
+	     * It's probably worth doing so.
+	     */
+	    managedObjectPropertyChange((T)source, evt);
+	}
+    };
+
+    public ManagedObjectMonitor(ManagedObject<T> objects)
+    {
+	objects_ = objects;
+	synchronized (objects_.getChildrenLock()) {
+	    objects_.addIntervalListener(this);
+	    listenees_.addAll(objects_.getChildren());
+	    for (T obj : objects_.getChildren())
+		obj.addPropertyChangeListener(managedObjectListener_);
+	}
+    }
+
+    public ManagedObjectMonitor()
+    {
+	this(new EmptyManagedObject<T>());
+    }
+
+
+    protected void managedObjectPropertyChange(T obj, PropertyChangeEvent evt)
+    {
+	/* Empty implementation; don't force subclasses to implement */
+    }
+
+    public ManagedObject<T> getManagedObject()
+    {
+	return objects_;
+    }
+
+    public void setManagedObject(ManagedObject<T> mo)
+    {
+	synchronized (this) {
+	    /*
+	     * Detach ourselves from the inner managed object
+	     */
+	    if (objects_ != null) {
+		synchronized (objects_.getChildrenLock()) {
+		    objects_.removeIntervalListener(this);
+		    int size = objects_.getChildren().size();
+		    if (size > 0)
+			intervalRemoved(
+			    new IntervalEvent(objects_, 0, size - 1));
+		}
+		objects_ = null;
+	    }
+
+	    /*
+	     * Attach ourselves to the new inner managed object
+	     */
+	    objects_ = (mo == null) ? new EmptyManagedObject<T>() : mo;
+	    synchronized (objects_.getChildrenLock()) {
+		int size = objects_.getChildren().size();
+		if (size > 0)
+		    intervalAdded(new IntervalEvent(objects_, 0, size - 1));
+		objects_.addIntervalListener(this);
+	    }
+	}
+    }
+
+    /*
+     * IntervalListener methods
+     */
+
+    @Override
+    public void intervalAdded(IntervalEvent event) {
+	List<T> inserted = objects_.getChildren().subList(event.getFirstIndex(),
+	    event.getLastIndex() + 1);
+	for (T obj : inserted)
+	    obj.addPropertyChangeListener(managedObjectListener_);
+	synchronized (listenees_) {
+	    listenees_.addAll(event.getFirstIndex(), inserted);
+	}
+    }
+
+    @Override
+    public void intervalRemoved(IntervalEvent event) {
+	synchronized (listenees_) {
+	    List<T> deleted = listenees_.subList(event.getFirstIndex(),
+		event.getLastIndex() + 1);
+	    for (T obj : deleted)
+		obj.removePropertyChangeListener(managedObjectListener_);
+	    deleted.clear();
+	}
+    }
+
+    /*
+     * PropertyChangeEventSource methods
+     */
+
+    public void addPropertyChangeListener(PropertyChangeListener l)
+    {
+	pListeners_.add(l);
+    }
+
+    public void addPropertyChangeListener(String property,
+	PropertyChangeListener l)
+    {
+	pListeners_.add(property, l);
+    }
+
+    public boolean removePropertyChangeListener(String property,
+	PropertyChangeListener l)
+    {
+	return (pListeners_.remove(property, l));
+    }
+
+    public boolean removePropertyChangeListener(PropertyChangeListener l)
+    {
+	return (pListeners_.remove(l));
+    }
+}