org.eclipse.jface.text/src/org/eclipse/jface/text/reconciler/AbstractReconciler.java - platform/eclipse.platform.text - Git at Google

 /*******************************************************************************
  * Copyright (c) 2000, 2003 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Common Public License v1.0
  * which accompanies this distribution, and is available at
  * http://www.eclipse.org/legal/cpl-v10.html
  *
  * Contributors:
  *     IBM Corporation - initial API and implementation
  *******************************************************************************/

 package org.eclipse.jface.text.reconciler;


 import org.eclipse.core.runtime.IProgressMonitor;

 import org.eclipse.jface.text.Assert;
 import org.eclipse.jface.text.DocumentEvent;
 import org.eclipse.jface.text.IDocument;
 import org.eclipse.jface.text.IDocumentListener;
 import org.eclipse.jface.text.ITextInputListener;
 import org.eclipse.jface.text.ITextViewer;


 /**
  * Abstract implementation of <code>IReconciler</code>. The reconciler
  * listens to input document changes as well as changes of
  * the input document of the text viewer it is installed on. Depending on
  * its configuration it manages the received change notifications in a
  * queue folding neighboring or overlapping changes together.  The reconciler
  * processes the dirty regions as a background activity after having waited for further
  * changes for the configured duration of time. A reconciler is started using its
  * <code>install</code> method.  As a first step <code>initialProcess</code> is
  * executed in the background. Then, the reconciling thread waits for changes that
  * need to be reconciled. A reconciler can be resumed by calling <code>forceReconciling</code>
  * independent from the existence of actual changes. This mechanism is for subclasses only.
  * It is the clients responsibility to stop a reconciler using its <code>uninstall</code>
  * method. Unstopped reconcilers do not free their resources.<p>
  * It is subclass responsibility to specify how dirty regions are processed.
  *
  * @see IReconciler
  * @see IDocumentListener
  * @see ITextInputListener
  * @see DirtyRegion
  * @since 2.0
  */
 abstract public class AbstractReconciler implements IReconciler {


 	/**
 	 * Background thread for the reconciling activity.
 	 */
 	class BackgroundThread extends Thread {

 		/** Has the reconciler been canceled */
 		private boolean fCanceled= false;
 		/** Has the reconciler been reset */
 		private boolean fReset= false;
 		/** Has a change been applied */
 		private boolean fIsDirty= false;
 		/** Is a reconciling strategy active */
 		private boolean fIsActive= false;

 		/**
 		 * Creates a new background thread. The thread
 		 * runs with minimal priority.
 		 *
 		 * @param name the thread's name
 		 */
 		public BackgroundThread(String name) {
 			super(name);
 			setPriority(Thread.MIN_PRIORITY);
 			setDaemon(true);
 		}

 		/**
 		 * Returns whether a reconciling strategy is active right now.
 		 *
 		 * @return <code>true</code> if a activity is active
 		 */
 		public boolean isActive() {
 			return fIsActive;
 		}

 		/**
 		 * Cancels the background thread.
 		 */
 		public void cancel() {
 			fCanceled= true;
 			synchronized (fDirtyRegionQueue) {
 				fDirtyRegionQueue.notifyAll();
 			}
 		}

 		/**
 		 * Suspends the caller of this method until this background thread has
 		 * emptied the dirty region queue.
 		 */
 		public void suspendCallerWhileDirty() {
 			while (fIsDirty) {
 				synchronized (fDirtyRegionQueue) {
 					if (fIsDirty) {
 						try {
 							fDirtyRegionQueue.wait();
 						} catch (InterruptedException x) {
 						}
 					}
 				}
 			}
 		}

 		/**
 		 * Reset the background thread as the text viewer has been changed,
 		 */
 		public void reset() {

 			if (fDelay > 0) {

 				synchronized (this) {
 					fIsDirty= true;
 					fReset= true;
 				}

 			} else {

 				synchronized(this) {
 					fIsDirty= true;
 				}

 				synchronized (fDirtyRegionQueue) {
 					fDirtyRegionQueue.notifyAll();
 				}
 			}

             reconcilerReset();
 		}

 		/**
 		 * The background activity. Waits until there is something in the
 		 * queue managing the changes that have been applied to the text viewer.
 		 * Removes the first change from the queue and process it.<p>
 		 * Calls <code>initialProcess</code> on entrance.
 		 */
 		public void run() {

 			synchronized (fDirtyRegionQueue) {
 				try {
 					fDirtyRegionQueue.wait(fDelay);
 				} catch (InterruptedException x) {
 				}
 			}

 			initialProcess();

 			while (!fCanceled) {

 				synchronized (fDirtyRegionQueue) {
 					try {
 						fDirtyRegionQueue.wait(fDelay);
 					} catch (InterruptedException x) {
 					}
 				}

 				if (fCanceled)
 					break;

 				if (!fIsDirty)
 					continue;

 				if (fReset) {
 					synchronized (this) {
 						fReset= false;
 					}
 					continue;
 				}

 				DirtyRegion r= null;
 				synchronized (fDirtyRegionQueue) {
 					r= fDirtyRegionQueue.removeNextDirtyRegion();
 				}

 				fIsActive= true;

 				if (fProgressMonitor != null)
 					fProgressMonitor.setCanceled(false);

 				process(r);

 				synchronized (fDirtyRegionQueue) {
 					if (0 == fDirtyRegionQueue.getSize()) {
 						synchronized (this) {
 							fIsDirty= false;
 						}
 						fDirtyRegionQueue.notifyAll();
 					}
 				}

 				fIsActive= false;
 			}
 		}
 	};

 	/**
 	 * Internal document listener and text input listener.
 	 */
 	class Listener implements IDocumentListener, ITextInputListener {

 		/*
 		 * @see IDocumentListener#documentAboutToBeChanged(DocumentEvent)
 		 */
 		public void documentAboutToBeChanged(DocumentEvent e) {
 		}

 		/*
 		 * @see IDocumentListener#documentChanged(DocumentEvent)
 		 */
 		public void documentChanged(DocumentEvent e) {

 			if (fProgressMonitor != null && fThread.isActive())
 				fProgressMonitor.setCanceled(true);

 			if (fIsIncrementalReconciler)
 				createDirtyRegion(e);

 			fThread.reset();
 		}

 		/*
 		 * @see ITextInputListener#inputDocumentAboutToBeChanged(IDocument, IDocument)
 		 */
 		public void inputDocumentAboutToBeChanged(IDocument oldInput, IDocument newInput) {

 			if (oldInput == fDocument) {

 				if (fDocument != null)
 					fDocument.removeDocumentListener(this);

 				if (fIsIncrementalReconciler) {
 					fDirtyRegionQueue.purgeQueue();
 					if (fDocument != null && fDocument.getLength() > 0) {
 						DocumentEvent e= new DocumentEvent(fDocument, 0, fDocument.getLength(), null);
 						createDirtyRegion(e);
 						fThread.suspendCallerWhileDirty();
 					}
 				}

 				fDocument= null;
 			}
 		}

 		/*
 		 * @see ITextInputListener#inputDocumentChanged(IDocument, IDocument)
 		 */
 		public void inputDocumentChanged(IDocument oldInput, IDocument newInput) {

 			fDocument= newInput;
 			if (fDocument == null)
 				return;


 			reconcilerDocumentChanged(fDocument);

 			fDocument.addDocumentListener(this);

 			if (fIsIncrementalReconciler) {
 				DocumentEvent e= new DocumentEvent(fDocument, 0, 0, fDocument.get());
 				createDirtyRegion(e);
 			}

 			startReconciling();
 		}
 	};

 	/** Queue to manage the changes applied to the text viewer */
 	private DirtyRegionQueue fDirtyRegionQueue;
 	/** The background thread */
 	private BackgroundThread fThread;
 	/** Internal document and text input listener */
 	private Listener fListener;
 	/** The background thread delay */
 	private int fDelay= 500;
 	/** Are there incremental reconciling strategies? */
 	private boolean fIsIncrementalReconciler= true;
 	/** The progress monitor used by this reconciler */
 	private IProgressMonitor fProgressMonitor;

 	/** The text viewer's document */
 	private IDocument fDocument;
 	/** The text viewer */
 	private ITextViewer fViewer;


 	/**
 	 * Processes a dirty region. If the dirty region is <code>null</code> the whole
 	 * document is consider being dirty. The dirty region is partitioned by the
 	 * document and each partition is handed over to a reconciling strategy registered
 	 * for the partition's content type.
 	 *
 	 * @param dirtyRegion the dirty region to be processed
 	 */
 	abstract protected void process(DirtyRegion dirtyRegion);

 	/**
 	 * Hook called when the document whose contents should be reconciled
 	 * has been changed, i.e., the input document of the text viewer this
 	 * reconciler is installed on. Usually, subclasses use this hook to
 	 * inform all their reconciling strategies about the change.
 	 *
 	 * @param newDocument the new reconciler document
 	 */
 	abstract protected void reconcilerDocumentChanged(IDocument newDocument);


 	/**
 	 * Creates a new reconciler without configuring it.
 	 */
 	protected AbstractReconciler() {
 		super();
 	}

 	/**
 	 * Tells the reconciler how long it should wait for further text changes before
 	 * activating the appropriate reconciling strategies.
 	 *
 	 * @param delay the duration in milli seconds of a change collection period.
 	 */
 	public void setDelay(int delay) {
 		fDelay= delay;
 	}

 	/**
 	 * Tells the reconciler whether any of the available reconciling strategies
 	 * is interested in getting detailed dirty region information or just in the
 	 * fact the the document has been changed. In the second case, the reconciling
 	 * can not incrementally be pursued.
 	 *
 	 * @param isIncremental indicates whether this reconciler will be configured with
 	 *		incremental reconciling strategies
 	 *
 	 * @see DirtyRegion
 	 * @see IReconcilingStrategy
 	 */
 	public void setIsIncrementalReconciler(boolean isIncremental) {
 		fIsIncrementalReconciler= isIncremental;
 	}

 	/**
 	 * Sets the progress monitor of this reconciler.
 	 *
 	 * @param monitor the monitor to be used
 	 */
 	public void setProgressMonitor(IProgressMonitor monitor) {
 		fProgressMonitor= monitor;
 	}

 	/**
 	 * Returns whether any of the reconciling strategies is interested in
 	 * detailed dirty region information.
 	 *
 	 * @return whether this reconciler is incremental
 	 *
 	 * @see IReconcilingStrategy
 	 */
 	protected boolean isIncrementalReconciler() {
 		return fIsIncrementalReconciler;
 	}

 	/**
 	 * Returns the input document of the text viewer this reconciler is installed on.
 	 *
 	 * @return the reconciler document
 	 */
 	protected IDocument getDocument() {
 		return fDocument;
 	}

 	/**
 	 * Returns the text viewer this reconciler is installed on.
 	 *
 	 * @return the text viewer this reconciler is installed on
 	 */
 	protected ITextViewer getTextViewer() {
 		return fViewer;
 	}

 	/**
 	 * Returns the progress monitor of this reconciler.
 	 *
 	 * @return the progress monitor of this reconciler
 	 */
 	protected IProgressMonitor getProgressMonitor() {
 		return fProgressMonitor;
 	}

 	/*
 	 * @see IReconciler#install(ITextViewer)
 	 */
 	public void install(ITextViewer textViewer) {

 		Assert.isNotNull(textViewer);

 		fViewer= textViewer;

 		fListener= new Listener();
 		fViewer.addTextInputListener(fListener);

 		fDirtyRegionQueue= new DirtyRegionQueue();
 		fThread= new BackgroundThread(getClass().getName());
 	}

 	/*
 	 * @see IReconciler#uninstall()
 	 */
 	public void uninstall() {
 		if (fListener != null) {

 			fViewer.removeTextInputListener(fListener);
 			if (fDocument != null) fDocument.removeDocumentListener(fListener);
 			fListener= null;

             synchronized (this) {
                 // http://dev.eclipse.org/bugs/show_bug.cgi?id=19135
     			BackgroundThread bt= fThread;
     			fThread= null;
     			bt.cancel();
             }
 		}
 	}

 	/**
 	 * Creates a dirty region for a document event and adds it to the queue.
 	 *
 	 * @param e the document event for which to create a dirty region
 	 */
 	private void createDirtyRegion(DocumentEvent e) {

 		if (e.getLength() == 0 && e.getText() != null) {
 			// Insert
 			fDirtyRegionQueue.addDirtyRegion(new DirtyRegion(e.getOffset(), e.getText().length(), DirtyRegion.INSERT, e.getText()));

 		} else if (e.getText() == null || e.getText().length() == 0) {
 			// Remove
 			fDirtyRegionQueue.addDirtyRegion(new DirtyRegion(e.getOffset(), e.getLength(), DirtyRegion.REMOVE, null));

 		} else {
 			// Replace (Remove + Insert)
 			fDirtyRegionQueue.addDirtyRegion(new DirtyRegion(e.getOffset(), e.getLength(), DirtyRegion.REMOVE, null));
 			fDirtyRegionQueue.addDirtyRegion(new DirtyRegion(e.getOffset(), e.getText().length(), DirtyRegion.INSERT, e.getText()));
 		}
 	}

 	/**
 	 * This method is called on startup of the background activity. It is called only
 	 * once during the life time of the reconciler. Clients may reimplement this method.
 	 */
 	protected void initialProcess() {
 	}

 	/**
 	 * Forces the reconciler to reconcile the structure of the whole document.
 	 * Clients may extend this method.
 	 */
 	protected void forceReconciling() {

 		if (fDocument != null) {

 			if (fIsIncrementalReconciler) {
 				DocumentEvent e= new DocumentEvent(fDocument, 0, fDocument.getLength(), fDocument.get());
 				createDirtyRegion(e);
 			}

 			startReconciling();
 		}
 	}

 	/**
 	 * Starts the reconciler to reconcile the queued dirty-regions.
 	 * Clients may extend this method.
 	 */
 	protected synchronized  void startReconciling() {
 		if (fThread == null)
 			return;

 		if (!fThread.isAlive())
 			fThread.start();

 		fThread.reset();
 	}

     /**
      * Hook that is called after the reconciler thread has been reset.
      */
     protected void reconcilerReset() {
     }
 }
	/*******************************************************************************
	* Copyright (c) 2000, 2003 IBM Corporation and others.
	* All rights reserved. This program and the accompanying materials
	* are made available under the terms of the Common Public License v1.0
	* which accompanies this distribution, and is available at
	* http://www.eclipse.org/legal/cpl-v10.html
	*
	* Contributors:
	* IBM Corporation - initial API and implementation
	*******************************************************************************/

	package org.eclipse.jface.text.reconciler;


	import org.eclipse.core.runtime.IProgressMonitor;

	import org.eclipse.jface.text.Assert;
	import org.eclipse.jface.text.DocumentEvent;
	import org.eclipse.jface.text.IDocument;
	import org.eclipse.jface.text.IDocumentListener;
	import org.eclipse.jface.text.ITextInputListener;
	import org.eclipse.jface.text.ITextViewer;




	/**
	* Abstract implementation of <code>IReconciler</code>. The reconciler
	* listens to input document changes as well as changes of
	* the input document of the text viewer it is installed on. Depending on
	* its configuration it manages the received change notifications in a
	* queue folding neighboring or overlapping changes together. The reconciler
	* processes the dirty regions as a background activity after having waited for further
	* changes for the configured duration of time. A reconciler is started using its
	* <code>install</code> method. As a first step <code>initialProcess</code> is
	* executed in the background. Then, the reconciling thread waits for changes that
	* need to be reconciled. A reconciler can be resumed by calling <code>forceReconciling</code>
	* independent from the existence of actual changes. This mechanism is for subclasses only.
	* It is the clients responsibility to stop a reconciler using its <code>uninstall</code>
	* method. Unstopped reconcilers do not free their resources.<p>
	* It is subclass responsibility to specify how dirty regions are processed.
	*
	* @see IReconciler
	* @see IDocumentListener
	* @see ITextInputListener
	* @see DirtyRegion
	* @since 2.0
	*/
	abstract public class AbstractReconciler implements IReconciler {


	/**
	* Background thread for the reconciling activity.
	*/
	class BackgroundThread extends Thread {

	/** Has the reconciler been canceled */
	private boolean fCanceled= false;
	/** Has the reconciler been reset */
	private boolean fReset= false;
	/** Has a change been applied */
	private boolean fIsDirty= false;
	/** Is a reconciling strategy active */
	private boolean fIsActive= false;

	/**
	* Creates a new background thread. The thread
	* runs with minimal priority.
	*
	* @param name the thread's name
	*/
	public BackgroundThread(String name) {
	super(name);
	setPriority(Thread.MIN_PRIORITY);
	setDaemon(true);
	}

	/**
	* Returns whether a reconciling strategy is active right now.
	*
	* @return <code>true</code> if a activity is active
	*/
	public boolean isActive() {
	return fIsActive;
	}

	/**
	* Cancels the background thread.
	*/
	public void cancel() {
	fCanceled= true;
	synchronized (fDirtyRegionQueue) {
	fDirtyRegionQueue.notifyAll();
	}
	}

	/**
	* Suspends the caller of this method until this background thread has
	* emptied the dirty region queue.
	*/
	public void suspendCallerWhileDirty() {
	while (fIsDirty) {
	synchronized (fDirtyRegionQueue) {
	if (fIsDirty) {
	try {
	fDirtyRegionQueue.wait();
	} catch (InterruptedException x) {
	}
	}
	}
	}
	}

	/**
	* Reset the background thread as the text viewer has been changed,
	*/
	public void reset() {

	if (fDelay > 0) {

	synchronized (this) {
	fIsDirty= true;
	fReset= true;
	}

	} else {

	synchronized(this) {
	fIsDirty= true;
	}

	synchronized (fDirtyRegionQueue) {
	fDirtyRegionQueue.notifyAll();
	}
	}

	reconcilerReset();
	}

	/**
	* The background activity. Waits until there is something in the
	* queue managing the changes that have been applied to the text viewer.
	* Removes the first change from the queue and process it.<p>
	* Calls <code>initialProcess</code> on entrance.
	*/
	public void run() {

	synchronized (fDirtyRegionQueue) {
	try {
	fDirtyRegionQueue.wait(fDelay);
	} catch (InterruptedException x) {
	}
	}

	initialProcess();

	while (!fCanceled) {

	synchronized (fDirtyRegionQueue) {
	try {
	fDirtyRegionQueue.wait(fDelay);
	} catch (InterruptedException x) {
	}
	}

	if (fCanceled)
	break;

	if (!fIsDirty)
	continue;

	if (fReset) {
	synchronized (this) {
	fReset= false;
	}
	continue;
	}

	DirtyRegion r= null;
	synchronized (fDirtyRegionQueue) {
	r= fDirtyRegionQueue.removeNextDirtyRegion();
	}

	fIsActive= true;

	if (fProgressMonitor != null)
	fProgressMonitor.setCanceled(false);

	process(r);

	synchronized (fDirtyRegionQueue) {
	if (0 == fDirtyRegionQueue.getSize()) {
	synchronized (this) {
	fIsDirty= false;
	}
	fDirtyRegionQueue.notifyAll();
	}
	}

	fIsActive= false;
	}
	}
	};

	/**
	* Internal document listener and text input listener.
	*/
	class Listener implements IDocumentListener, ITextInputListener {

	/*
	* @see IDocumentListener#documentAboutToBeChanged(DocumentEvent)
	*/
	public void documentAboutToBeChanged(DocumentEvent e) {
	}

	/*
	* @see IDocumentListener#documentChanged(DocumentEvent)
	*/
	public void documentChanged(DocumentEvent e) {

	if (fProgressMonitor != null && fThread.isActive())
	fProgressMonitor.setCanceled(true);

	if (fIsIncrementalReconciler)
	createDirtyRegion(e);

	fThread.reset();
	}

	/*
	* @see ITextInputListener#inputDocumentAboutToBeChanged(IDocument, IDocument)
	*/
	public void inputDocumentAboutToBeChanged(IDocument oldInput, IDocument newInput) {

	if (oldInput == fDocument) {

	if (fDocument != null)
	fDocument.removeDocumentListener(this);

	if (fIsIncrementalReconciler) {
	fDirtyRegionQueue.purgeQueue();
	if (fDocument != null && fDocument.getLength() > 0) {
	DocumentEvent e= new DocumentEvent(fDocument, 0, fDocument.getLength(), null);
	createDirtyRegion(e);
	fThread.suspendCallerWhileDirty();
	}
	}

	fDocument= null;
	}
	}

	/*
	* @see ITextInputListener#inputDocumentChanged(IDocument, IDocument)
	*/
	public void inputDocumentChanged(IDocument oldInput, IDocument newInput) {

	fDocument= newInput;
	if (fDocument == null)
	return;


	reconcilerDocumentChanged(fDocument);

	fDocument.addDocumentListener(this);

	if (fIsIncrementalReconciler) {
	DocumentEvent e= new DocumentEvent(fDocument, 0, 0, fDocument.get());
	createDirtyRegion(e);
	}

	startReconciling();
	}
	};

	/** Queue to manage the changes applied to the text viewer */
	private DirtyRegionQueue fDirtyRegionQueue;
	/** The background thread */
	private BackgroundThread fThread;
	/** Internal document and text input listener */
	private Listener fListener;
	/** The background thread delay */
	private int fDelay= 500;
	/** Are there incremental reconciling strategies? */
	private boolean fIsIncrementalReconciler= true;
	/** The progress monitor used by this reconciler */
	private IProgressMonitor fProgressMonitor;

	/** The text viewer's document */
	private IDocument fDocument;
	/** The text viewer */
	private ITextViewer fViewer;


	/**
	* Processes a dirty region. If the dirty region is <code>null</code> the whole
	* document is consider being dirty. The dirty region is partitioned by the
	* document and each partition is handed over to a reconciling strategy registered
	* for the partition's content type.
	*
	* @param dirtyRegion the dirty region to be processed
	*/
	abstract protected void process(DirtyRegion dirtyRegion);

	/**
	* Hook called when the document whose contents should be reconciled
	* has been changed, i.e., the input document of the text viewer this
	* reconciler is installed on. Usually, subclasses use this hook to
	* inform all their reconciling strategies about the change.
	*
	* @param newDocument the new reconciler document
	*/
	abstract protected void reconcilerDocumentChanged(IDocument newDocument);


	/**
	* Creates a new reconciler without configuring it.
	*/
	protected AbstractReconciler() {
	super();
	}

	/**
	* Tells the reconciler how long it should wait for further text changes before
	* activating the appropriate reconciling strategies.
	*
	* @param delay the duration in milli seconds of a change collection period.
	*/
	public void setDelay(int delay) {
	fDelay= delay;
	}

	/**
	* Tells the reconciler whether any of the available reconciling strategies
	* is interested in getting detailed dirty region information or just in the
	* fact the the document has been changed. In the second case, the reconciling
	* can not incrementally be pursued.
	*
	* @param isIncremental indicates whether this reconciler will be configured with
	* incremental reconciling strategies
	*
	* @see DirtyRegion
	* @see IReconcilingStrategy
	*/
	public void setIsIncrementalReconciler(boolean isIncremental) {
	fIsIncrementalReconciler= isIncremental;
	}

	/**
	* Sets the progress monitor of this reconciler.
	*
	* @param monitor the monitor to be used
	*/
	public void setProgressMonitor(IProgressMonitor monitor) {
	fProgressMonitor= monitor;
	}

	/**
	* Returns whether any of the reconciling strategies is interested in
	* detailed dirty region information.
	*
	* @return whether this reconciler is incremental
	*
	* @see IReconcilingStrategy
	*/
	protected boolean isIncrementalReconciler() {
	return fIsIncrementalReconciler;
	}

	/**
	* Returns the input document of the text viewer this reconciler is installed on.
	*
	* @return the reconciler document
	*/
	protected IDocument getDocument() {
	return fDocument;
	}

	/**
	* Returns the text viewer this reconciler is installed on.
	*
	* @return the text viewer this reconciler is installed on
	*/
	protected ITextViewer getTextViewer() {
	return fViewer;
	}

	/**
	* Returns the progress monitor of this reconciler.
	*
	* @return the progress monitor of this reconciler
	*/
	protected IProgressMonitor getProgressMonitor() {
	return fProgressMonitor;
	}

	/*
	* @see IReconciler#install(ITextViewer)
	*/
	public void install(ITextViewer textViewer) {

	Assert.isNotNull(textViewer);

	fViewer= textViewer;

	fListener= new Listener();
	fViewer.addTextInputListener(fListener);

	fDirtyRegionQueue= new DirtyRegionQueue();
	fThread= new BackgroundThread(getClass().getName());
	}

	/*
	* @see IReconciler#uninstall()
	*/
	public void uninstall() {
	if (fListener != null) {

	fViewer.removeTextInputListener(fListener);
	if (fDocument != null) fDocument.removeDocumentListener(fListener);
	fListener= null;

	synchronized (this) {
	// http://dev.eclipse.org/bugs/show_bug.cgi?id=19135
	BackgroundThread bt= fThread;
	fThread= null;
	bt.cancel();
	}
	}
	}

	/**
	* Creates a dirty region for a document event and adds it to the queue.
	*
	* @param e the document event for which to create a dirty region
	*/
	private void createDirtyRegion(DocumentEvent e) {

	if (e.getLength() == 0 && e.getText() != null) {
	// Insert
	fDirtyRegionQueue.addDirtyRegion(new DirtyRegion(e.getOffset(), e.getText().length(), DirtyRegion.INSERT, e.getText()));

	} else if (e.getText() == null \|\| e.getText().length() == 0) {
	// Remove
	fDirtyRegionQueue.addDirtyRegion(new DirtyRegion(e.getOffset(), e.getLength(), DirtyRegion.REMOVE, null));

	} else {
	// Replace (Remove + Insert)
	fDirtyRegionQueue.addDirtyRegion(new DirtyRegion(e.getOffset(), e.getLength(), DirtyRegion.REMOVE, null));
	fDirtyRegionQueue.addDirtyRegion(new DirtyRegion(e.getOffset(), e.getText().length(), DirtyRegion.INSERT, e.getText()));
	}
	}

	/**
	* This method is called on startup of the background activity. It is called only
	* once during the life time of the reconciler. Clients may reimplement this method.
	*/
	protected void initialProcess() {
	}

	/**
	* Forces the reconciler to reconcile the structure of the whole document.
	* Clients may extend this method.
	*/
	protected void forceReconciling() {

	if (fDocument != null) {

	if (fIsIncrementalReconciler) {
	DocumentEvent e= new DocumentEvent(fDocument, 0, fDocument.getLength(), fDocument.get());
	createDirtyRegion(e);
	}

	startReconciling();
	}
	}

	/**
	* Starts the reconciler to reconcile the queued dirty-regions.
	* Clients may extend this method.
	*/
	protected synchronized void startReconciling() {
	if (fThread == null)
	return;

	if (!fThread.isAlive())
	fThread.start();

	fThread.reset();
	}

	/**
	* Hook that is called after the reconciler thread has been reset.
	*/
	protected void reconcilerReset() {
	}
	}