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
IWorkbenchWindow[] windows= PlatformUI.getWorkbench().getWorkbenchWindows();
		for (int i= 0, length= windows.length; i < length; i++)
			windows[i].getPartService().addPartListener(fActivationListener);
	}
	private void activeJavaEditorChanged(IWorkbenchPart editor) {
		IJavaElement javaElement= null;
		if (editor instanceof JavaEditor)
			javaElement= ((JavaEditor)editor).getInputJavaElement();
		synchronized (this) {
			fActiveEditor= editor;
			fActiveJavaElement= javaElement;
		}
		if (DEBUG)
			System.out.println(getThreadName() + " - " + DEBUG_PREFIX + "active editor is: " + toString(javaElement)); 
		synchronized (fReconcileLock) {
			if (fIsReconciling && !fReconcilingJavaElement.equals(javaElement)) {
				fIsReconciling= false;
				fReconcilingJavaElement= null;
			}
		}
		cache(null, javaElement);
	}
	/**
	 * Returns whether the given compilation unit AST is
	 * cached by this AST provided.
	 *
	 * @param ast the compilation unit AST
	 * @return <code>true</code> if the given AST is the cached one
	 */
	public boolean isCached(CompilationUnit ast) {