Extract Reconciler Job Into an own class

Currently the BackgroundThread is an inner class of the
AbstractReconciler and is tightly coupled with it what makes it quite
hard to understand the interaction between both and to properly update a
reconciler on document changes or refactor the code.

This is a first attempt to decouple the things by extracting the inner
class in an own (package private) type to allow further refactoring
operations and proper encapsulation.

Author: laeubi

bundles/org.eclipse.jface.text/src/org/eclipse/jface/text/reconciler/AbstractReconciler.java

@@ -15,9 +15,7 @@
 
 import org.eclipse.core.runtime.Assert;
 import org.eclipse.core.runtime.IProgressMonitor;
-import org.eclipse.core.runtime.IStatus;
 import org.eclipse.core.runtime.NullProgressMonitor;
-import org.eclipse.core.runtime.Status;
 import org.eclipse.core.runtime.jobs.Job;
 
 import org.eclipse.jface.text.DocumentEvent;
@@ -52,201 +50,6 @@
  */
 abstract public class AbstractReconciler implements IReconciler {
 
-
-	/**
-	 * Background thread for the reconciling activity.
-	 */
-	private class BackgroundThread extends Job {
-
-		/** Has the reconciler been canceled. */
-		private boolean fCanceled= false;
-		/** Has the reconciler been reset. */
-		private boolean fReset= false;
-		/** Some changes need to be processed. */
-		private boolean fIsDirty= false;
-		/** Is a reconciling strategy active. */
-		private boolean fIsActive= false;
-
-		private volatile boolean fIsAlive;
-
-		private boolean started;
-
-		/**
-		 * Creates a new background thread. The thread
-		 * runs with minimal priority.
-		 *
-		 * @param name the thread's name
-		 */
-		public BackgroundThread(String name) {
-			super(name);
-			setPriority(Job.DECORATE);
-			setSystem(true);
-		}
-
-		/**
-		 * Returns whether a reconciling strategy is active right now.
-		 *
-		 * @return <code>true</code> if a activity is active
-		 */
-		public boolean isActive() {
-			return fIsActive;
-		}
-
-		/**
-		 * Returns whether some changes need to be processed.
-		 *
-		 * @return <code>true</code> if changes wait to be processed
-		 * @since 3.0
-		 */
-		public synchronized boolean isDirty() {
-			return fIsDirty;
-		}
-
-		/**
-		 * Cancels the background thread.
-		 */
-		public void doCancel() {
-			fCanceled= true;
-			IProgressMonitor pm= fProgressMonitor;
-			if (pm != null)
-				pm.setCanceled(true);
-			synchronized (fDirtyRegionQueue) {
-				fDirtyRegionQueue.notifyAll();
-			}
-		}
-
-		/**
-		 * Suspends the caller of this method until this background thread has
-		 * emptied the dirty region queue.
-		 */
-		public void suspendCallerWhileDirty() {
-			AbstractReconciler.this.signalWaitForFinish();
-			boolean isDirty;
-			do {
-				synchronized (fDirtyRegionQueue) {
-					isDirty= fDirtyRegionQueue.getSize() > 0;
-					if (isDirty) {
-						try {
-							fDirtyRegionQueue.wait();
-						} catch (InterruptedException x) {
-						}
-					}
-				}
-			} while (isDirty);
-		}
-
-		/**
-		 * Reset the background thread as the text viewer has been changed,
-		 */
-		public void reset() {
-
-			if (fDelay > 0) {
-
-				synchronized (this) {
-					fIsDirty= true;
-					fReset= true;
-				}
-				synchronized (fDirtyRegionQueue) {
-					fDirtyRegionQueue.notifyAll(); // wake up wait(fDelay);
-				}
-
-			} else {
-
-				synchronized (this) {
-					fIsDirty= true;
-				}
-
-				synchronized (fDirtyRegionQueue) {
-					fDirtyRegionQueue.notifyAll();
-				}
-			}
-			synchronized (this) {
-				started= false;
-			}
-			informNotFinished();
-			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 {@link AbstractReconciler#initialProcess()} on entrance.
-		 * </p>
-		 */
-		@Override
-		public IStatus run(IProgressMonitor monitor) {
-			fIsAlive= true;
-			delay();
-
-			if (fCanceled)
-				return Status.CANCEL_STATUS;
-
-			initialProcess();
-
-			while (!fCanceled) {
-
-				delay();
-
-				if (fCanceled)
-					break;
-
-				if (!isDirty()) {
-					waitFinish= false; //signalWaitForFinish() was called but nothing todo
-					continue;
-				}
-
-				synchronized (this) {
-					if (fReset) {
-						fReset= false;
-						continue;
-					}
-				}
-
-				DirtyRegion r= null;
-				synchronized (fDirtyRegionQueue) {
-					r= fDirtyRegionQueue.removeNextDirtyRegion();
-				}
-
-				fIsActive= true;
-
-				fProgressMonitor.setCanceled(false);
-
-				process(r);
-
-				synchronized (fDirtyRegionQueue) {
-					if (0 == fDirtyRegionQueue.getSize()) {
-						synchronized (this) {
-							fIsDirty= fProgressMonitor.isCanceled();
-						}
-						fDirtyRegionQueue.notifyAll();
-					}
-				}
-
-				fIsActive= false;
-			}
-			fIsAlive= false;
-			return Status.OK_STATUS;
-		}
-
-		public boolean isAlive() {
-			return fIsAlive;
-		}
-
-		public synchronized void start() {
-			if (!started) {
-				started= true;
-				schedule();
-			}
-		}
-
-		@Override
-		public boolean belongsTo(Object family) {
-			return family == fViewer || AbstractReconciler.class == family;
-		}
-	}
-
 	/**
 	 * Internal document listener and text input listener.
 	 */
@@ -323,13 +126,14 @@ public void inputDocumentChanged(IDocument oldInput, IDocument newInput) {
 	}
 
 	/** Queue to manage the changes applied to the text viewer. */
-	private DirtyRegionQueue fDirtyRegionQueue;
+	DirtyRegionQueue fDirtyRegionQueue;
 	/** The background thread. */
-	private BackgroundThread fThread;
+	private ReconcilerJob fThread;
 	/** Internal document and text input listener. */
 	private Listener fListener;
+
 	/** The background thread delay. */
-	private int fDelay= 500;
+	int fDelay= 500;
 	/** Signal that the the background thread should not delay. */
 	volatile boolean waitFinish;
 	/** Are there incremental reconciling strategies? */
@@ -476,7 +280,7 @@ public void install(ITextViewer textViewer) {
 		synchronized (this) {
 			if (fThread != null)
 				return;
-			fThread= new BackgroundThread(getClass().getName());
+			fThread= new ReconcilerJob(getClass().getName(), this);
 		}
 
 		fDirtyRegionQueue= new DirtyRegionQueue();
@@ -510,7 +314,7 @@ public void uninstall() {
 
 			synchronized (this) {
 				// http://dev.eclipse.org/bugs/show_bug.cgi?id=19135
-				BackgroundThread bt= fThread;
+				ReconcilerJob bt= fThread;
 				fThread= null;
 				bt.doCancel();
 			}
@@ -579,7 +383,7 @@ public void signalWaitForFinish() {
 		}
 	}
 
-	private void informNotFinished() {
+	void informNotFinished() {
 		waitFinish= false;
 		aboutToWork();
 	}
@@ -590,7 +394,7 @@ private void aboutToBeReconciledInternal() {
 	}
 
 
-	private void delay() {
+	void delay() {
 		synchronized (fDirtyRegionQueue) {
 			if (waitFinish) {
 				return; // do not delay when waiting;