Class Scheduler

java.lang.Object
org.jgroups.util.Scheduler
All Implemented Interfaces:
Runnable

public class Scheduler extends Object implements Runnable
Implementation of a priority scheduler. The scheduler maintains a queue to the end of which all tasks are added. It continually looks at the first queue element, assigns a thread to it, runs the thread and waits for completion. When a new priority task is added, it will be added to the head of the queue and the scheduler will be interrupted. In this case, the currently handled task is suspended, and the one at the head of the queue handled. This is recursive: a priority task can always be interrupted by another priority task. Recursion ends when no more priority tasks are added, or when the thread pool is exhausted.
Author:
Bela Ban
  • Field Details

    • log

      protected static final org.apache.commons.logging.Log log
  • Constructor Details

    • Scheduler

      public Scheduler()
    • Scheduler

      public Scheduler(int num_threads)
  • Method Details

    • setListener

      public void setListener(SchedulerListener l)
    • getConcurrentProcessing

      public boolean getConcurrentProcessing()
    • setConcurrentProcessing

      public void setConcurrentProcessing(boolean process_concurrently)
    • run

      public void run()
      Specified by:
      run in interface Runnable
    • addPrio

      public void addPrio(Runnable task)
    • add

      public void add(Runnable task)
    • start

      public void start()
    • stop

      public void stop()
      Stop the scheduler thread. The thread may be waiting for its next task (queue.peek()) or it may be waiting on the currently executing thread. In the first case, closing the queue will throw a QueueClosed exception which terminates the scheduler thread. In the second case, after closing the queue, we interrupt the scheduler thread, which then checks whether the queue is closed. If this is the case, the scheduler thread terminates.