code: public void start() throws ContextClientCodeException {
      synchronized (this.contextStack) {
        LOG.log(Level.FINEST, "Instantiating root context.");
        this.contextStack.push(this.launchContext.get().getRootContext());
  
        if (this.launchContext.get().getInitialTaskConfiguration().isPresent()) {
          LOG.log(Level.FINEST, "Launching the initial Task");
          try {
            this.contextStack.peek().startTask(this.launchContext.get().getInitialTaskConfiguration().get());
          } catch (final TaskClientCodeException e) {
            this.handleTaskException(e);
          }
        }
      }
    }
docs: Start the context manager. This initiates the root context.
  
  @throws ContextClientCodeException if the root context can't be instantiated.