Bug 96219 [implementation] OperationCanceledException gets logged
N20050521-0010 OperationCanceledException gets logged if reconcile is canceled during Java editor reconcile or if AST creation is canceled during AST Provider's AST creation.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/javaeditor/ASTProvider.java
/**
	 * Returns a shared compilation unit AST for the given
	 * Java element.
	 * <p>
	 * Clients are not allowed to modify the AST and must
	 * synchronize all access to its nodes.
	 * </p>
	 *
	 * @param je				the Java element
	 * @param waitFlag			{@link #WAIT_YES}, {@link #WAIT_NO} or {@link #WAIT_ACTIVE_ONLY}
	 * @param progressMonitor	the progress monitor
	 * @return					the AST or <code>null</code> if the AST is not available
	 */
	public CompilationUnit getAST(IJavaElement je, WAIT_FLAG waitFlag, IProgressMonitor progressMonitor) {
		Assert.isTrue(je != null && (je.getElementType() == IJavaElement.CLASS_FILE || je.getElementType() == IJavaElement.COMPILATION_UNIT));
		if (progressMonitor != null && progressMonitor.isCanceled())
			return null;
		boolean isActiveElement;
		synchronized (this) {
			isActiveElement= je.equals(fActiveJavaElement);
			if (isActiveElement) {
				if (fAST != null) {
					if (DEBUG)
						System.out.println(getThreadName() + " - " + DEBUG_PREFIX + "returning cached AST:" + toString(fAST) + " for: " + je.getElementName()); 
					return fAST;
				}
				if (waitFlag == WAIT_NO) {
					if (DEBUG)
						System.out.println(getThreadName() + " - " + DEBUG_PREFIX + "returning null (WAIT_NO) for: " + je.getElementName()); 
					return null;