What kind of task you want to schedule in the scheduler? I guess it is possible to read the value from property file instead of hard coding into XML file. 'Start time' and 'Repeat time' is read at that time of server startup so later on even if you change any of those values you got to restart the server to see the effect.
Generally, Scheduler is used to create a daemon process which will run forever until you stop the server. For example, it can be used to send the emails to all the ranchers who have put watch on some topic.