code: public Future<Void> loadNB()
      {
          Callable<Void> task = new Callable<Void>()
          {
              @Override
              public Void call() throws Exception
              {
                  properties.load(getFile());
                  firePropertiesLoaded();
                  return null;
              }
          };
  
          return executor.submit(task);
      }
docs: Load the properties file. This will override all current values with
  whatever has last been saved.<br>
  <br>
  This method will not block to wait for the properties to be loaded. See
  {@link #load()} for a blocking version.
  
  @return a {@link Future} representing this load request