bundles/org.eclipse.wst.xml.core/src/org/eclipse/wst/xml/core/internal/document/XMLModelNotifierImpl.java - sourceediting/webtools.sourceediting - Git at Google

 /*******************************************************************************
  * Copyright (c) 2001, 2004 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
  * http://www.eclipse.org/legal/epl-v10.html
  *
  * Contributors:
  *     IBM Corporation - initial API and implementation
  *     Jens Lukowski/Innoopract - initial renaming/restructuring
  *
  *******************************************************************************/
 package org.eclipse.wst.xml.core.internal.document;

 import java.util.Iterator;
 import java.util.Vector;

 import org.eclipse.wst.sse.core.internal.provisional.INodeNotifier;
 import org.eclipse.wst.sse.core.internal.util.Debug;
 import org.eclipse.wst.xml.core.internal.Logger;
 import org.eclipse.wst.xml.core.internal.provisional.document.IDOMNode;
 import org.w3c.dom.Attr;
 import org.w3c.dom.Element;
 import org.w3c.dom.Node;


 public class XMLModelNotifierImpl implements XMLModelNotifier {

 	/* end: for debugging only */
 	private class NotifyEvent {
 		Object changedFeature;
 		boolean discarded;
 		Object newValue;
 		// note: don't initialize instance variables, since
 		// that causes double assignments, and lots of these are created.
 		INodeNotifier notifier;
 		Object oldValue;
 		int pos;
 		String reason;
 		int type;

 		NotifyEvent(INodeNotifier notifier, int type, Object changedFeature, Object oldValue, Object newValue, int pos) {
 			this.notifier = notifier;
 			this.type = type;
 			this.changedFeature = changedFeature;
 			this.oldValue = oldValue;
 			this.newValue = newValue;
 			this.pos = pos;
 			this.reason = ""; //$NON-NLS-1$
 		}
 	}

 	private final static String ADDED_THEN_REMOVED = "Discard: Added then removed rule"; //$NON-NLS-1$
 	private final static boolean fOptimizeDeferred = true;
 	private final static boolean fOptimizeDeferredAccordingToParentAdded = true;
 	private final static boolean fOptimizeDeferredAccordingToParentRemoved = true;
 	private final static String PARENT_IS_ADDED = "Disarded: Parent has just been added"; //$NON-NLS-1$
 	/* start: for debugging only */
 	private final static String PARENT_IS_REMOVED_TOO = "Discard: Parent was removed too"; //$NON-NLS-1$
 	private final static String PARENT_IS_REPARENTED = "Not Discard: Parent was removed so this implies reparenting"; //$NON-NLS-1$
 	private Node changedRoot = null;

 	private boolean changing = false;
 	private boolean doingNewModel = false;
 	private Vector events = null;
 	private boolean flushing = false;

 	/**
 	 */
 	public XMLModelNotifierImpl() {
 		super();
 	}

 	/**
 	 * attrReplaced method
 	 *
 	 * @param element
 	 *            org.w3c.dom.Element
 	 * @param newAttr
 	 *            org.w3c.dom.Attr
 	 * @param oldAttr
 	 *            org.w3c.dom.Attr
 	 */
 	public void attrReplaced(Element element, Attr newAttr, Attr oldAttr) {
 		if (element == null)
 			return;
 		Attr attr = null;
 		String oldValue = null;
 		String newValue = null;
 		if (oldAttr != null) {
 			attr = oldAttr;
 			oldValue = oldAttr.getValue();
 		}
 		if (newAttr != null) {
 			attr = newAttr;
 			newValue = newAttr.getValue();
 		}
 		IDOMNode notifier = (IDOMNode) element;
 		int offset = notifier.getStartOffset();
 		notify(notifier, INodeNotifier.CHANGE, attr, oldValue, newValue, offset);
 		propertyChanged(notifier);
 	}

 	/**
 	 */
 	public void beginChanging() {
 		this.changing = true;
 	}

 	/**
 	 */
 	public void beginChanging(boolean newModel) {
 		beginChanging();
 		this.doingNewModel = newModel;
 	}

 	public void cancelPending() {
 		// we don't want to change the size of this array, since
 		// the array may be being processed, in the defferred notification
 		// loop, but we can signal that all
 		// should be discarded, so any remaining ones will be ignored.
 		if (this.events != null) {
 			Iterator iterator = this.events.iterator();
 			while (iterator.hasNext()) {
 				NotifyEvent event = (NotifyEvent) iterator.next();
 				event.discarded = true;
 			}
 		}
 		// this cancel is presumably being called as a function of
 		// "reinitiailization" so we can ignore changes to the
 		// old root, and changes to the new one will be triggered during
 		// reinitialization.
 		changedRoot = null;
 	}

 	/**
 	 * childReplaced method
 	 *
 	 * @param parentNode
 	 *            org.w3c.dom.Node
 	 * @param newChild
 	 *            org.w3c.dom.Node
 	 * @param oldChild
 	 *            org.w3c.dom.Node
 	 */
 	public void childReplaced(Node parentNode, Node newChild, Node oldChild) {
 		if (parentNode == null)
 			return;
 		IDOMNode notifier = (IDOMNode) parentNode;
 		int type = INodeNotifier.CHANGE;
 		if (newChild == null)
 			type = INodeNotifier.REMOVE;
 		else if (oldChild == null)
 			type = INodeNotifier.ADD;
 		int offset = notifier.getStartOffset();
 		notify(notifier, type, oldChild, oldChild, newChild, offset);
 		structureChanged(notifier);
 	}

 	public void editableChanged(Node node) {
 		if (node == null)
 			return;
 		IDOMNode notifier = (IDOMNode) node;
 		int offset = notifier.getStartOffset();
 		notify(notifier, INodeNotifier.CHANGE, null, null, null, offset);
 		propertyChanged(notifier);
 	}

 	/**
 	 */
 	public void endChanging() {
 		this.doingNewModel = false;
 		if (!this.changing)
 			return; // avoid nesting calls
 		notifyDeferred();
 		if (this.changedRoot != null) {
 			notifyStructureChanged(this.changedRoot);
 			if (Debug.debugNotifyDeferred) {
 				String p = this.changedRoot.getNodeName();
 				System.out.println("Deferred STRUCUTRE_CHANGED: " + p); //$NON-NLS-1$
 			}
 			this.changedRoot = null;
 		}
 		this.changing = false;
 	}

 	/**
 	 */
 	public void endTagChanged(Element element) {
 		if (element == null)
 			return;
 		IDOMNode notifier = (IDOMNode) element;
 		int offset = notifier.getStartOffset();
 		notify(notifier, INodeNotifier.CHANGE, null, null, null, offset);
 		propertyChanged(element);
 	}

 	/**
 	 */
 	public boolean hasChanged() {
 		return (this.events != null);
 	}

 	/**
 	 */
 	public boolean isChanging() {
 		return this.changing;
 	}

 	/**
 	 */
 	private void notify(INodeNotifier notifier, int eventType, Object changedFeature, Object oldValue, Object newValue, int pos) {
 		if (notifier == null)
 			return;
 		if (this.changing && !this.flushing) {
 			// defer notification
 			if (this.events == null)
 				this.events = new Vector();
 			// we do not defer anything if we are doing a new Model,
 			// except for the document event, since all others are
 			// trivial and not needed at that initial point.
 			// But even for that one document event, in the new model case,
 			// it is still important to defer it.
 			if ((!doingNewModel) || (((Node) notifier).getNodeType() == Node.DOCUMENT_NODE)) {
 				this.events.addElement(new NotifyEvent(notifier, eventType, changedFeature, oldValue, newValue, pos));
 			}
 			return;
 		}
 		try {
 			// Its important to "keep going" if exception occurs, since this
 			// notification
 			// comes in between "about to change" and "changed" events. We do
 			// log, however,
 			// since would indicate a program error.
 			notifier.notify(eventType, changedFeature, oldValue, newValue, pos);
 		} catch (Exception e) {
 			Logger.logException("A structured model client threw following exception during adapter notification (" + INodeNotifier.EVENT_TYPE_STRINGS[eventType] + " )", e); //$NON-NLS-1$ //$NON-NLS-2$
 		}
 	}

 	/**
 	 */
 	private void notifyDeferred() {
 		if (this.events == null)
 			return;
 		if (this.flushing)
 			return;
 		this.flushing = true; // force notification
 		int count = this.events.size();
 		for (int i = 0; i < count; i++) {
 			NotifyEvent event = (NotifyEvent) this.events.elementAt(i);
 			if (event == null)
 				continue; // error
 			if (event.discarded)
 				continue;
 			if (!doingNewModel && fOptimizeDeferred) {
 				// check redundant events (no need to check if doing NewModel,
 				// since
 				// shouldn't be redunancies)
 				if (event.type == INodeNotifier.ADD) {
 					for (int n = i + 1; n < count; n++) {
 						NotifyEvent next = (NotifyEvent) this.events.elementAt(n);
 						if (next == null)
 							continue; // error
 						if (next.type == INodeNotifier.REMOVE && next.oldValue == event.newValue) {
 							// Added then removed later, discard both
 							event.discarded = true;
 							next.discarded = true;
 							if (Debug.debugNotifyDeferred) {
 								event.reason = event.reason + ADDED_THEN_REMOVED + "(see " + n + ")"; //$NON-NLS-1$ //$NON-NLS-2$
 								next.reason = next.reason + ADDED_THEN_REMOVED + "(see " + i + ")"; //$NON-NLS-1$ //$NON-NLS-2$
 							}
 							break;
 						}
 					}
 					if (event.discarded)
 						continue;
 					if (fOptimizeDeferredAccordingToParentAdded) {
 						for (int p = 0; p < i; p++) {
 							NotifyEvent prev = (NotifyEvent) this.events.elementAt(p);
 							if (prev == null)
 								continue; // error
 							if (prev.type == INodeNotifier.REMOVE && prev.oldValue == event.notifier) {
 								// parent is reparented, do not discard
 								if (Debug.debugNotifyDeferred) {
 									event.reason = event.reason + PARENT_IS_REPARENTED + "(see " + p + ")"; //$NON-NLS-1$ //$NON-NLS-2$
 								}
 								break;
 							} else if (prev.type == INodeNotifier.ADD && prev.newValue == event.notifier) {
 								// parent has been added, discard this
 								event.discarded = true;
 								if (Debug.debugNotifyDeferred) {
 									event.reason = event.reason + PARENT_IS_ADDED + "(see " + p + ")"; //$NON-NLS-1$ //$NON-NLS-2$
 								}
 								break;
 							}
 						}
 						if (event.discarded)
 							continue;
 					}
 				} else if (event.type == INodeNotifier.REMOVE) {
 					if (fOptimizeDeferredAccordingToParentRemoved) {
 						for (int n = i + 1; n < count; n++) {
 							NotifyEvent next = (NotifyEvent) this.events.elementAt(n);
 							if (next == null)
 								continue; // error
 							if (next.type == INodeNotifier.REMOVE) {
 								if (next.oldValue == event.notifier) {
 									// parent will be removed, discard this
 									event.discarded = true;
 									if (Debug.debugNotifyDeferred) {
 										event.reason = event.reason + PARENT_IS_REMOVED_TOO + "(see " + n + ")"; //$NON-NLS-1$ //$NON-NLS-2$
 									}
 									break;
 								}
 							}
 						}
 						if (event.discarded)
 							continue;
 					}
 				}
 			}
 			notify(event.notifier, event.type, event.changedFeature, event.oldValue, event.newValue, event.pos);
 		}
 		if (Debug.debugNotifyDeferred) {
 			for (int l = 0; l < count; l++) {
 				NotifyEvent event = (NotifyEvent) this.events.elementAt(l);
 				Object o = null;
 				String t = null;
 				if (event.type == INodeNotifier.ADD) {
 					o = event.newValue;
 					t = " + "; //$NON-NLS-1$
 				} else if (event.type == INodeNotifier.REMOVE) {
 					o = event.oldValue;
 					t = " - "; //$NON-NLS-1$
 				}
 				if (o instanceof Element) {
 					String p = ((Node) event.notifier).getNodeName();
 					String c = ((Node) o).getNodeName();
 					String d = (event.discarded ? "! " : "  "); //$NON-NLS-1$ //$NON-NLS-2$
 					System.out.println(d + p + t + c);
 				}
 			}
 		}
 		this.flushing = false;
 		this.events = null;
 	}

 	/**
 	 */
 	private void notifyStructureChanged(Node root) {
 		if (root == null)
 			return;
 		INodeNotifier notifier = (INodeNotifier) root;
 		try {
 			// Its important to "keep going" if exception occurs, since this
 			// notification
 			// comes in between "about to change" and "changed" events. We do
 			// log, however,
 			// since would indicate a program error.
 			notifier.notify(INodeNotifier.STRUCTURE_CHANGED, null, null, null, -1);
 		} catch (Exception e) {
 			Logger.logException("A structured model client threw following exception during adapter notification (" + INodeNotifier.EVENT_TYPE_STRINGS[INodeNotifier.STRUCTURE_CHANGED] + " )", e); //$NON-NLS-1$ //$NON-NLS-2$
 		}

 	}

 	/**
 	 */
 	public void propertyChanged(Node node) {
 	}

 	/**
 	 * @param node
 	 */
 	private void setCommonRootIfNeeded(Node node) {
 		// defer notification
 		if (this.changedRoot == null) {
 			this.changedRoot = node;
 		} else {
 			// tiny optimization: if previous commonAncestor (changedRoot) is
 			// already 'document',
 			// or if already equal to this 'node',
 			// then no need to re-calculate
 			if (changedRoot.getNodeType() != Node.DOCUMENT_NODE && changedRoot != node) {
 				Node common = ((NodeImpl) this.changedRoot).getCommonAncestor(node);
 				if (common != null)
 					this.changedRoot = common;
 				else
 					this.changedRoot = node;
 			}
 		}
 	}

 	/**
 	 */
 	public void startTagChanged(Element element) {
 		if (element == null)
 			return;
 		IDOMNode notifier = (IDOMNode) element;
 		int offset = notifier.getStartOffset();
 		notify(notifier, INodeNotifier.CHANGE, null, null, null, offset);
 		propertyChanged(element);
 	}

 	/**
 	 */
 	public void structureChanged(Node node) {
 		if (node == null)
 			return;
 		if (isChanging()) {
 			setCommonRootIfNeeded(node);
 			if (Debug.debugNotifyDeferred) {
 				String p = this.changedRoot.getNodeName();
 				System.out.println("requested STRUCUTRE_CHANGED: " + p); //$NON-NLS-1$
 			}
 			return;
 		}
 		if (Debug.debugNotifyDeferred) {
 			String p = node.getNodeName();
 			System.out.println("STRUCUTRE_CHANGED: " + p); //$NON-NLS-1$
 		}
 		notifyStructureChanged(node);
 	}

 	/**
 	 * valueChanged method
 	 *
 	 * @param node
 	 *            org.w3c.dom.Node
 	 */
 	public void valueChanged(Node node) {
 		if (node == null)
 			return;
 		IDOMNode notifier = null;
 		if (node.getNodeType() == Node.ATTRIBUTE_NODE) {
 			Attr attr = (Attr) node;
 			notifier = (IDOMNode) attr.getOwnerElement();
 			// TODO_dmw: experimental: changed 06/29/2004 to send "strucuture
 			// changed" even for attribute value changes
 			// there are pros and cons to considering attribute value
 			// "structure changed". Will (re)consider
 			// setCommonRootIfNeeded(notifier);
 			if (notifier == null)
 				return;
 			String value = attr.getValue();
 			int offset = notifier.getStartOffset();
 			notify(notifier, INodeNotifier.CHANGE, attr, null, value, offset);
 		} else {
 			// note: we do not send structured changed event for content
 			// changed
 			notifier = (IDOMNode) node;
 			String value = node.getNodeValue();
 			int offset = notifier.getStartOffset();
 			notify(notifier, INodeNotifier.CHANGE, null, null, value, offset);
 			if (node.getNodeType() != Node.ELEMENT_NODE) {
 				IDOMNode parent = (IDOMNode) node.getParentNode();
 				if (parent != null) {
 					notify(parent, INodeNotifier.CONTENT_CHANGED, node, null, value, offset);
 				}
 			}
 		}
 		propertyChanged(notifier);
 	}
 }
	/*******************************************************************************
	* Copyright (c) 2001, 2004 IBM Corporation and others.
	* All rights reserved. This program and the accompanying materials
	* are made available under the terms of the Eclipse Public License v1.0
	* which accompanies this distribution, and is available at
	* http://www.eclipse.org/legal/epl-v10.html
	*
	* Contributors:
	* IBM Corporation - initial API and implementation
	* Jens Lukowski/Innoopract - initial renaming/restructuring
	*
	*******************************************************************************/
	package org.eclipse.wst.xml.core.internal.document;

	import java.util.Iterator;
	import java.util.Vector;

	import org.eclipse.wst.sse.core.internal.provisional.INodeNotifier;
	import org.eclipse.wst.sse.core.internal.util.Debug;
	import org.eclipse.wst.xml.core.internal.Logger;
	import org.eclipse.wst.xml.core.internal.provisional.document.IDOMNode;
	import org.w3c.dom.Attr;
	import org.w3c.dom.Element;
	import org.w3c.dom.Node;


	public class XMLModelNotifierImpl implements XMLModelNotifier {

	/* end: for debugging only */
	private class NotifyEvent {
	Object changedFeature;
	boolean discarded;
	Object newValue;
	// note: don't initialize instance variables, since
	// that causes double assignments, and lots of these are created.
	INodeNotifier notifier;
	Object oldValue;
	int pos;
	String reason;
	int type;

	NotifyEvent(INodeNotifier notifier, int type, Object changedFeature, Object oldValue, Object newValue, int pos) {
	this.notifier = notifier;
	this.type = type;
	this.changedFeature = changedFeature;
	this.oldValue = oldValue;
	this.newValue = newValue;
	this.pos = pos;
	this.reason = ""; //$NON-NLS-1$
	}
	}

	private final static String ADDED_THEN_REMOVED = "Discard: Added then removed rule"; //$NON-NLS-1$
	private final static boolean fOptimizeDeferred = true;
	private final static boolean fOptimizeDeferredAccordingToParentAdded = true;
	private final static boolean fOptimizeDeferredAccordingToParentRemoved = true;
	private final static String PARENT_IS_ADDED = "Disarded: Parent has just been added"; //$NON-NLS-1$
	/* start: for debugging only */
	private final static String PARENT_IS_REMOVED_TOO = "Discard: Parent was removed too"; //$NON-NLS-1$
	private final static String PARENT_IS_REPARENTED = "Not Discard: Parent was removed so this implies reparenting"; //$NON-NLS-1$
	private Node changedRoot = null;

	private boolean changing = false;
	private boolean doingNewModel = false;
	private Vector events = null;
	private boolean flushing = false;

	/**
	*/
	public XMLModelNotifierImpl() {
	super();
	}

	/**
	* attrReplaced method
	*
	* @param element
	* org.w3c.dom.Element
	* @param newAttr
	* org.w3c.dom.Attr
	* @param oldAttr
	* org.w3c.dom.Attr
	*/
	public void attrReplaced(Element element, Attr newAttr, Attr oldAttr) {
	if (element == null)
	return;
	Attr attr = null;
	String oldValue = null;
	String newValue = null;
	if (oldAttr != null) {
	attr = oldAttr;
	oldValue = oldAttr.getValue();
	}
	if (newAttr != null) {
	attr = newAttr;
	newValue = newAttr.getValue();
	}
	IDOMNode notifier = (IDOMNode) element;
	int offset = notifier.getStartOffset();
	notify(notifier, INodeNotifier.CHANGE, attr, oldValue, newValue, offset);
	propertyChanged(notifier);
	}

	/**
	*/
	public void beginChanging() {
	this.changing = true;
	}

	/**
	*/
	public void beginChanging(boolean newModel) {
	beginChanging();
	this.doingNewModel = newModel;
	}

	public void cancelPending() {
	// we don't want to change the size of this array, since
	// the array may be being processed, in the defferred notification
	// loop, but we can signal that all
	// should be discarded, so any remaining ones will be ignored.
	if (this.events != null) {
	Iterator iterator = this.events.iterator();
	while (iterator.hasNext()) {
	NotifyEvent event = (NotifyEvent) iterator.next();
	event.discarded = true;
	}
	}
	// this cancel is presumably being called as a function of
	// "reinitiailization" so we can ignore changes to the
	// old root, and changes to the new one will be triggered during
	// reinitialization.
	changedRoot = null;
	}

	/**
	* childReplaced method
	*
	* @param parentNode
	* org.w3c.dom.Node
	* @param newChild
	* org.w3c.dom.Node
	* @param oldChild
	* org.w3c.dom.Node
	*/
	public void childReplaced(Node parentNode, Node newChild, Node oldChild) {
	if (parentNode == null)
	return;
	IDOMNode notifier = (IDOMNode) parentNode;
	int type = INodeNotifier.CHANGE;
	if (newChild == null)
	type = INodeNotifier.REMOVE;
	else if (oldChild == null)
	type = INodeNotifier.ADD;
	int offset = notifier.getStartOffset();
	notify(notifier, type, oldChild, oldChild, newChild, offset);
	structureChanged(notifier);
	}

	public void editableChanged(Node node) {
	if (node == null)
	return;
	IDOMNode notifier = (IDOMNode) node;
	int offset = notifier.getStartOffset();
	notify(notifier, INodeNotifier.CHANGE, null, null, null, offset);
	propertyChanged(notifier);
	}

	/**
	*/
	public void endChanging() {
	this.doingNewModel = false;
	if (!this.changing)
	return; // avoid nesting calls
	notifyDeferred();
	if (this.changedRoot != null) {
	notifyStructureChanged(this.changedRoot);
	if (Debug.debugNotifyDeferred) {
	String p = this.changedRoot.getNodeName();
	System.out.println("Deferred STRUCUTRE_CHANGED: " + p); //$NON-NLS-1$
	}
	this.changedRoot = null;
	}
	this.changing = false;
	}

	/**
	*/
	public void endTagChanged(Element element) {
	if (element == null)
	return;
	IDOMNode notifier = (IDOMNode) element;
	int offset = notifier.getStartOffset();
	notify(notifier, INodeNotifier.CHANGE, null, null, null, offset);
	propertyChanged(element);
	}

	/**
	*/
	public boolean hasChanged() {
	return (this.events != null);
	}

	/**
	*/
	public boolean isChanging() {
	return this.changing;
	}

	/**
	*/
	private void notify(INodeNotifier notifier, int eventType, Object changedFeature, Object oldValue, Object newValue, int pos) {
	if (notifier == null)
	return;
	if (this.changing && !this.flushing) {
	// defer notification
	if (this.events == null)
	this.events = new Vector();
	// we do not defer anything if we are doing a new Model,
	// except for the document event, since all others are
	// trivial and not needed at that initial point.
	// But even for that one document event, in the new model case,
	// it is still important to defer it.
	if ((!doingNewModel) \|\| (((Node) notifier).getNodeType() == Node.DOCUMENT_NODE)) {
	this.events.addElement(new NotifyEvent(notifier, eventType, changedFeature, oldValue, newValue, pos));
	}
	return;
	}
	try {
	// Its important to "keep going" if exception occurs, since this
	// notification
	// comes in between "about to change" and "changed" events. We do
	// log, however,
	// since would indicate a program error.
	notifier.notify(eventType, changedFeature, oldValue, newValue, pos);
	} catch (Exception e) {
	Logger.logException("A structured model client threw following exception during adapter notification (" + INodeNotifier.EVENT_TYPE_STRINGS[eventType] + " )", e); //$NON-NLS-1$ //$NON-NLS-2$
	}
	}

	/**
	*/
	private void notifyDeferred() {
	if (this.events == null)
	return;
	if (this.flushing)
	return;
	this.flushing = true; // force notification
	int count = this.events.size();
	for (int i = 0; i < count; i++) {
	NotifyEvent event = (NotifyEvent) this.events.elementAt(i);
	if (event == null)
	continue; // error
	if (event.discarded)
	continue;
	if (!doingNewModel && fOptimizeDeferred) {
	// check redundant events (no need to check if doing NewModel,
	// since
	// shouldn't be redunancies)
	if (event.type == INodeNotifier.ADD) {
	for (int n = i + 1; n < count; n++) {
	NotifyEvent next = (NotifyEvent) this.events.elementAt(n);
	if (next == null)
	continue; // error
	if (next.type == INodeNotifier.REMOVE && next.oldValue == event.newValue) {
	// Added then removed later, discard both
	event.discarded = true;
	next.discarded = true;
	if (Debug.debugNotifyDeferred) {
	event.reason = event.reason + ADDED_THEN_REMOVED + "(see " + n + ")"; //$NON-NLS-1$ //$NON-NLS-2$
	next.reason = next.reason + ADDED_THEN_REMOVED + "(see " + i + ")"; //$NON-NLS-1$ //$NON-NLS-2$
	}
	break;
	}
	}
	if (event.discarded)
	continue;
	if (fOptimizeDeferredAccordingToParentAdded) {
	for (int p = 0; p < i; p++) {
	NotifyEvent prev = (NotifyEvent) this.events.elementAt(p);
	if (prev == null)
	continue; // error
	if (prev.type == INodeNotifier.REMOVE && prev.oldValue == event.notifier) {
	// parent is reparented, do not discard
	if (Debug.debugNotifyDeferred) {
	event.reason = event.reason + PARENT_IS_REPARENTED + "(see " + p + ")"; //$NON-NLS-1$ //$NON-NLS-2$
	}
	break;
	} else if (prev.type == INodeNotifier.ADD && prev.newValue == event.notifier) {
	// parent has been added, discard this
	event.discarded = true;
	if (Debug.debugNotifyDeferred) {
	event.reason = event.reason + PARENT_IS_ADDED + "(see " + p + ")"; //$NON-NLS-1$ //$NON-NLS-2$
	}
	break;
	}
	}
	if (event.discarded)
	continue;
	}
	} else if (event.type == INodeNotifier.REMOVE) {
	if (fOptimizeDeferredAccordingToParentRemoved) {
	for (int n = i + 1; n < count; n++) {
	NotifyEvent next = (NotifyEvent) this.events.elementAt(n);
	if (next == null)
	continue; // error
	if (next.type == INodeNotifier.REMOVE) {
	if (next.oldValue == event.notifier) {
	// parent will be removed, discard this
	event.discarded = true;
	if (Debug.debugNotifyDeferred) {
	event.reason = event.reason + PARENT_IS_REMOVED_TOO + "(see " + n + ")"; //$NON-NLS-1$ //$NON-NLS-2$
	}
	break;
	}
	}
	}
	if (event.discarded)
	continue;
	}
	}
	}
	notify(event.notifier, event.type, event.changedFeature, event.oldValue, event.newValue, event.pos);
	}
	if (Debug.debugNotifyDeferred) {
	for (int l = 0; l < count; l++) {
	NotifyEvent event = (NotifyEvent) this.events.elementAt(l);
	Object o = null;
	String t = null;
	if (event.type == INodeNotifier.ADD) {
	o = event.newValue;
	t = " + "; //$NON-NLS-1$
	} else if (event.type == INodeNotifier.REMOVE) {
	o = event.oldValue;
	t = " - "; //$NON-NLS-1$
	}
	if (o instanceof Element) {
	String p = ((Node) event.notifier).getNodeName();
	String c = ((Node) o).getNodeName();
	String d = (event.discarded ? "! " : " "); //$NON-NLS-1$ //$NON-NLS-2$
	System.out.println(d + p + t + c);
	}
	}
	}
	this.flushing = false;
	this.events = null;
	}

	/**
	*/
	private void notifyStructureChanged(Node root) {
	if (root == null)
	return;
	INodeNotifier notifier = (INodeNotifier) root;
	try {
	// Its important to "keep going" if exception occurs, since this
	// notification
	// comes in between "about to change" and "changed" events. We do
	// log, however,
	// since would indicate a program error.
	notifier.notify(INodeNotifier.STRUCTURE_CHANGED, null, null, null, -1);
	} catch (Exception e) {
	Logger.logException("A structured model client threw following exception during adapter notification (" + INodeNotifier.EVENT_TYPE_STRINGS[INodeNotifier.STRUCTURE_CHANGED] + " )", e); //$NON-NLS-1$ //$NON-NLS-2$
	}

	}

	/**
	*/
	public void propertyChanged(Node node) {
	}

	/**
	* @param node
	*/
	private void setCommonRootIfNeeded(Node node) {
	// defer notification
	if (this.changedRoot == null) {
	this.changedRoot = node;
	} else {
	// tiny optimization: if previous commonAncestor (changedRoot) is
	// already 'document',
	// or if already equal to this 'node',
	// then no need to re-calculate
	if (changedRoot.getNodeType() != Node.DOCUMENT_NODE && changedRoot != node) {
	Node common = ((NodeImpl) this.changedRoot).getCommonAncestor(node);
	if (common != null)
	this.changedRoot = common;
	else
	this.changedRoot = node;
	}
	}
	}

	/**
	*/
	public void startTagChanged(Element element) {
	if (element == null)
	return;
	IDOMNode notifier = (IDOMNode) element;
	int offset = notifier.getStartOffset();
	notify(notifier, INodeNotifier.CHANGE, null, null, null, offset);
	propertyChanged(element);
	}

	/**
	*/
	public void structureChanged(Node node) {
	if (node == null)
	return;
	if (isChanging()) {
	setCommonRootIfNeeded(node);
	if (Debug.debugNotifyDeferred) {
	String p = this.changedRoot.getNodeName();
	System.out.println("requested STRUCUTRE_CHANGED: " + p); //$NON-NLS-1$
	}
	return;
	}
	if (Debug.debugNotifyDeferred) {
	String p = node.getNodeName();
	System.out.println("STRUCUTRE_CHANGED: " + p); //$NON-NLS-1$
	}
	notifyStructureChanged(node);
	}

	/**
	* valueChanged method
	*
	* @param node
	* org.w3c.dom.Node
	*/
	public void valueChanged(Node node) {
	if (node == null)
	return;
	IDOMNode notifier = null;
	if (node.getNodeType() == Node.ATTRIBUTE_NODE) {
	Attr attr = (Attr) node;
	notifier = (IDOMNode) attr.getOwnerElement();
	// TODO_dmw: experimental: changed 06/29/2004 to send "strucuture
	// changed" even for attribute value changes
	// there are pros and cons to considering attribute value
	// "structure changed". Will (re)consider
	// setCommonRootIfNeeded(notifier);
	if (notifier == null)
	return;
	String value = attr.getValue();
	int offset = notifier.getStartOffset();
	notify(notifier, INodeNotifier.CHANGE, attr, null, value, offset);
	} else {
	// note: we do not send structured changed event for content
	// changed
	notifier = (IDOMNode) node;
	String value = node.getNodeValue();
	int offset = notifier.getStartOffset();
	notify(notifier, INodeNotifier.CHANGE, null, null, value, offset);
	if (node.getNodeType() != Node.ELEMENT_NODE) {
	IDOMNode parent = (IDOMNode) node.getParentNode();
	if (parent != null) {
	notify(parent, INodeNotifier.CONTENT_CHANGED, node, null, value, offset);
	}
	}
	}
	propertyChanged(notifier);
	}
	}