public void testIsDirty() throws IOException, CoreException {
   IStructuredModel model = getTestModel();
   try {
     assertFalse("model should not be dirty", model.isDirty());
   } finally {
     if (model != null) {
       model.releaseFromEdit();
     }
   }
 }
  /**
   * Method validateEdit.
   *
   * @param file org.eclipse.core.resources.IFile
   * @param context org.eclipse.swt.widgets.Shell
   * @return IStatus
   */
  private static IStatus validateEdit(IFile file, Shell context) {
    if (file == null || !file.exists()) return STATUS_ERROR;
    if (!(file.isReadOnly())) return STATUS_OK;

    IPath location = file.getLocation();

    final long beforeModifiedFromJavaIO =
        (location != null) ? location.toFile().lastModified() : IResource.NULL_STAMP;
    final long beforeModifiedFromIFile = file.getModificationStamp();

    IStatus status = ResourcesPlugin.getWorkspace().validateEdit(new IFile[] {file}, context);
    if (!status.isOK()) return status;

    final long afterModifiedFromJavaIO =
        (location != null) ? location.toFile().lastModified() : IResource.NULL_STAMP;
    final long afterModifiedFromIFile = file.getModificationStamp();

    if (beforeModifiedFromJavaIO != afterModifiedFromJavaIO
        || beforeModifiedFromIFile != afterModifiedFromIFile) {
      IModelManager manager = StructuredModelManager.getModelManager();
      IStructuredModel model = manager.getExistingModelForRead(file);
      if (model != null) {
        if (!model.isDirty()) {
          try {
            file.refreshLocal(IResource.DEPTH_ONE, null);
          } catch (CoreException e) {
            return STATUS_ERROR;
          } finally {
            model.releaseFromRead();
          }
        } else {
          model.releaseFromRead();
        }
      }
    }

    if ((beforeModifiedFromJavaIO != afterModifiedFromJavaIO)
        || (beforeModifiedFromIFile != afterModifiedFromIFile)) {
      // the file is replaced. Modification cannot be
      // applied.
      return STATUS_ERROR;
    }
    return STATUS_OK;
  }