code: private void setTasks(String tasks) {
  		for (String task : tasks.split(",")) {
  			if (KNOWN_TASKS.containsKey(task)) {
  				this.tasks |= KNOWN_TASKS.get(task);
  				this.taskName += (this.taskName.isEmpty() ? "" : "-") + task;
  			} else {
  				logger.warn("Unsupported RDF serialization task \"" + task
  						+ "\". Run without specifying any tasks for help.");
  			}
  		}
  	}
docs: Sets the RDF serialization tasks based on the given string value.
  
  @param tasks
  a space-free, comma-separated list of task names