Package org.jgroups.util

Class TimeScheduler2

java.lang.Object
org.jgroups.util.TimeScheduler2
All Implemented Interfaces:
Runnable, ThreadManager, TimeScheduler
public class TimeScheduler2 extends Object implements TimeScheduler, Runnable
Implementation of TimeScheduler. Uses a thread pool and a single thread which waits for the next task to be executed. When ready, it passes the task to the associated pool to get executed. When multiple tasks are scheduled to get executed at the same time, they're collected in a queue associated with the task execution time, and are executed together.
Author:
Bela Ban

  • Field Details

    • no_tasks

      protected final AtomicBoolean no_tasks
      Needed to signal going from 0 tasks to non-zero (we cannot use tasks.isEmpty() here ...)

    • running

      protected volatile boolean running

    • log

      protected static final Log log

    • threadDecorator

      protected ThreadDecorator threadDecorator

    • timer_thread_factory

      protected ThreadFactory timer_thread_factory

    • SLEEP_TIME

      protected static final long SLEEP_TIME
      See Also:

  • Constructor Details

    • TimeScheduler2

      public TimeScheduler2()
      Create a scheduler that executes tasks in dynamically adjustable intervals

    • TimeScheduler2

      public TimeScheduler2(ThreadFactory factory, int min_threads, int max_threads, long keep_alive_time, int max_queue_size)

    • TimeScheduler2

      public TimeScheduler2(int corePoolSize)

  • Method Details

    • getThreadDecorator

      public ThreadDecorator getThreadDecorator()
      Description copied from interface: ThreadManager
      Gets the ThreadDecorator associated with this manager.
      Specified by:
      getThreadDecorator in interface ThreadManager
      Returns:
      the ThreadDecorator, or null if there is none.

    • setThreadDecorator

      public void setThreadDecorator(ThreadDecorator threadDecorator)
      Description copied from interface: ThreadManager
      Sets the ThreadDecorator associated this manager should use.
      Specified by:
      setThreadDecorator in interface ThreadManager
      Parameters:
      threadDecorator - the ThreadDecorator, or null.

    • setThreadFactory

      public void setThreadFactory(ThreadFactory factory)
      Specified by:
      setThreadFactory in interface TimeScheduler

    • getMinThreads

      public int getMinThreads()
      Description copied from interface: TimeScheduler
      Returns the configured core threads, or -1 if not applicable
      Specified by:
      getMinThreads in interface TimeScheduler
      Returns:

    • setMinThreads

      public void setMinThreads(int size)
      Description copied from interface: TimeScheduler
      Sets the core pool size. Can be ignored if not applicable
      Specified by:
      setMinThreads in interface TimeScheduler

    • getMaxThreads

      public int getMaxThreads()
      Description copied from interface: TimeScheduler
      Returns the configured max threads, or -1 if not applicable
      Specified by:
      getMaxThreads in interface TimeScheduler
      Returns:

    • setMaxThreads

      public void setMaxThreads(int size)
      Description copied from interface: TimeScheduler
      Sets the max pool size. Can be ignored if not applicable
      Specified by:
      setMaxThreads in interface TimeScheduler

    • getKeepAliveTime

      public long getKeepAliveTime()
      Description copied from interface: TimeScheduler
      Returns the keep alive time (in ms) of the thread pool, or -1 if not applicable
      Specified by:
      getKeepAliveTime in interface TimeScheduler

    • setKeepAliveTime

      public void setKeepAliveTime(long time)
      Description copied from interface: TimeScheduler
      Sets the keep alive time (in ms) of the thread pool. Can be ignored if not applicable
      Specified by:
      setKeepAliveTime in interface TimeScheduler

    • getCurrentThreads

      public int getCurrentThreads()
      Description copied from interface: TimeScheduler
      Returns the current threads in the pool, or -1 if not applicable
      Specified by:
      getCurrentThreads in interface TimeScheduler
      Returns:

    • getQueueSize

      public int getQueueSize()

    • dumpTimerTasks

      public String dumpTimerTasks()
      Description copied from interface: TimeScheduler
      Returns a list of tasks currently waiting for execution. If there are a lot of tasks, the returned string should probably only return the number of tasks rather than a full dump.
      Specified by:
      dumpTimerTasks in interface TimeScheduler
      Returns:

    • execute

      public void execute(Runnable task)
      Description copied from interface: TimeScheduler
      Executes command with zero required delay. This has effect equivalent to schedule(command, 0, anyUnit).
      Specified by:
      execute in interface TimeScheduler
      Parameters:
      task - the task to execute

    • schedule

      public Future<?> schedule(Runnable work, long delay, TimeUnit unit)
      Description copied from interface: TimeScheduler
      Creates and executes a one-shot action that becomes enabled after the given delay.
      Specified by:
      schedule in interface TimeScheduler
      Parameters:
      work - the task to execute
      delay - the time from now to delay execution
      unit - the time unit of the delay parameter
      Returns:
      a ScheduledFuture representing pending completion of the task and whose get() method will return null upon completion

    • scheduleWithFixedDelay

      public Future<?> scheduleWithFixedDelay(Runnable task, long initial_delay, long delay, TimeUnit unit)
      Description copied from interface: TimeScheduler
      Creates and executes a periodic action that becomes enabled first after the given initial delay, and subsequently with the given delay between the termination of one execution and the commencement of the next. If any execution of the task encounters an exception, subsequent executions are suppressed. Otherwise, the task will only terminate via cancellation or termination of the executor.
      Specified by:
      scheduleWithFixedDelay in interface TimeScheduler
      Parameters:
      task - the task to execute
      initial_delay - the time to delay first execution
      delay - the delay between the termination of one execution and the commencement of the next
      unit - the time unit of the initialDelay and delay parameters
      Returns:
      a ScheduledFuture representing pending completion of the task, and whose get() method will throw an exception upon cancellation

    • scheduleAtFixedRate

      public Future<?> scheduleAtFixedRate(Runnable task, long initial_delay, long delay, TimeUnit unit)
      Description copied from interface: TimeScheduler
      Creates and executes a periodic action that becomes enabled first after the given initial delay, and subsequently with the given period; that is executions will commence after initialDelay then initialDelay+period, then initialDelay + 2 * period, and so on. If any execution of the task encounters an exception, subsequent executions are suppressed. Otherwise, the task will only terminate via cancellation or termination of the executor. If any execution of this task takes longer than its period, then subsequent executions may start late, but will not concurrently execute.
      Specified by:
      scheduleAtFixedRate in interface TimeScheduler
      Parameters:
      task - the task to execute
      initial_delay - the time to delay first execution
      delay - the period between successive executions
      unit - the time unit of the initialDelay and period parameters
      Returns:
      a ScheduledFuture representing pending completion of the task, and whose get() method will throw an exception upon cancellation

    • scheduleWithDynamicInterval

      public Future<?> scheduleWithDynamicInterval(TimeScheduler.Task task)
      Schedule a task for execution at varying intervals. After execution, the task will get rescheduled after TimeScheduler.Task.nextInterval() milliseconds. The task is neve done until nextInterval() return a value invalid input: '<'= 0 or the task is cancelled.
      Specified by:
      scheduleWithDynamicInterval in interface TimeScheduler
      Parameters:
      task - the task to execute Task is rescheduled relative to the last time it actually started execution

      false:
      Task is scheduled relative to its last execution schedule. This has the effect that the time between two consecutive executions of the task remains the same.

      Note that relative is always true; we always schedule the next execution relative to the last *actual*

    • size

      public int size()
      Returns the number of tasks currently in the timer
      Specified by:
      size in interface TimeScheduler
      Returns:
      The number of tasks currently in the timer

    • toString

      public String toString()
      Overrides:
      toString in class Object

    • stop

      public void stop()
      Stops the timer, cancelling all tasks
      Specified by:
      stop in interface TimeScheduler
      Throws:
      InterruptedException - if interrupted while waiting for thread to return

    • isShutdown

      public boolean isShutdown()
      Description copied from interface: TimeScheduler
      Returns true if stop() has been called, false otherwise
      Specified by:
      isShutdown in interface TimeScheduler

    • run

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

    • _run

      protected void _run()

    • init

      protected void init()

    • waitUntilNextExecution

      protected void waitUntilNextExecution()
      Sleeps until the next task in line is ready to be executed

    • waitFor

      protected void waitFor()

    • taskReady

      protected void taskReady(long trigger_time)
      Signals that a task with a lower execution time than next_execution_time is ready

    • startRunner

      protected void startRunner()

    • stopRunner

      protected void stopRunner()