code: private void removeActivityWithConstraints(String activity) {
  		Validate.notNull(activity);
  		Validate.notEmpty(activity);
  		Set<String> currentActivities = getActivitiesWithRoutingConstraints();
  		currentActivities.remove(activity);
  		setProperty(ConstraintContextProperty.ACTIVITIES_WITH_CONSTRAINTS, ArrayUtils.toString(currentActivities.toArray()));
  	}
docs: Removes an activity from the list of activities with routing constraints.
  @param activity The name of the activity to remove.
  @throws ParameterException if the activity name is invalid.