Class Scheduler

java.lang.Object
   |
   +----Scheduler

public abstract class Scheduler

extends Object

Scheduler()

add(Job, int)

Add a new job wanting service.

printQueue()

For debugging: print the queue of waiting jobs

printStats()

Print statistics about the history of this queue.

queueChanged(int)

This method should be called by a subclass whenever the queue length changes.

remove()

Retrieve (and remove) the next job to be served.

reschedule(int)

This method is called when there is a clock interrupt.

 public Scheduler()

 public abstract boolean add(Job j,
                             int timeLeft)

Add a new job wanting service. The second argument is the amount of time remaining before the job currently using the device will finish (-1 if the device is idle). Return TRUE if this scheduler would like to preempt the current job.

 public abstract Job remove()

Retrieve (and remove) the next job to be served. Return null if there is no such job.

 public abstract boolean reschedule(int timeLeft)

This method is called when there is a clock interrupt. It returns true if there is a reason to stop the current process and run another one instead. The argument is the amount of time left until the current job finishes service on the device.

 public abstract void printQueue()

For debugging: print the queue of waiting jobs

 protected void queueChanged(int amount)

This method should be called by a subclass whenever the queue length changes.

 public void printStats()

Print statistics about the history of this queue.