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java.util

Class Timer

java.lang.Object
|
+--java.util.Timer


public class Timer

extends Object

Timer that can run TimerTasks at a later time. TimerTasks can be scheduled for one time execution at some time in the future. They can be scheduled to be rescheduled at a time period after the task was last executed. Or they can be scheduled to be executed repeatedly at a fixed rate.

The normal scheduling will result in a more or less even delay in time between successive executions, but the executions could drift in time if the task (or other tasks) takes a long time to execute. Fixed delay scheduling guarantees more or less that the task will be executed at a specific time, but if there is ever a delay in execution then the period between successive executions will be shorter. The first method of repeated scheduling is preferred for repeated tasks in response to user interaction, the second method of repeated scheduling is preferred for tasks that act like alarms.

The Timer keeps a binary heap as a task priority queue which means that scheduling and serving of a task in a queue of n tasks costs O(log n).

Since:Author:See Also:

Constructor Summary

Timer()

Creates a new Timer with a non daemon Thread as Scheduler, with normal priority and a default name.
Timer(boolean daemon)

Creates a new Timer with a daemon Thread as scheduler if daemon is true, with normal priority and a default name.

Method Summary

voidcancel()

Cancels the execution of the scheduler.
voidfinalize()

Tells the scheduler that the Timer task died so there will be no more new tasks scheduled.
voidschedule(java.util.TimerTask task, java.util.Date date)

Schedules the task at the specified data for one time execution.
voidschedule(java.util.TimerTask task, java.util.Date date, long period)

Schedules the task at the specified date and reschedules the task every period milliseconds after the last execution of the task finishes until this timer or the task is canceled.
voidschedule(java.util.TimerTask task, long delay)

Schedules the task after the specified delay milliseconds for one time execution.
voidschedule(java.util.TimerTask task, long delay, long period)

Schedules the task after the delay milliseconds and reschedules the task every period milliseconds after the last execution of the task finishes until this timer or the task is canceled.
voidscheduleAtFixedRate(java.util.TimerTask task, java.util.Date date, long period)

Schedules the task at the specified date and reschedules the task at a fixed rate every period milliseconds until this timer or the task is canceled.
voidscheduleAtFixedRate(java.util.TimerTask task, long delay, long period)

Schedules the task after the delay milliseconds and reschedules the task at a fixed rate every period milliseconds until this timer or the task is canceled.

Constructor Details

Timer

public Timer()

Creates a new Timer with a non daemon Thread as Scheduler, with normal priority and a default name.


Timer

public Timer(boolean daemon)

Creates a new Timer with a daemon Thread as scheduler if daemon is true, with normal priority and a default name.

Parameters:


Method Details

cancel

public void cancel()

Cancels the execution of the scheduler. If a task is executing it will normally finish execution, but no other tasks will be executed and no more tasks can be scheduled.


finalize

protected void finalize()

Tells the scheduler that the Timer task died so there will be no more new tasks scheduled.


schedule

public void schedule(java.util.TimerTask task, java.util.Date date)

Schedules the task at the specified data for one time execution.

Parameters:

Throws:


schedule

public void schedule(java.util.TimerTask task, java.util.Date date, long period)

Schedules the task at the specified date and reschedules the task every period milliseconds after the last execution of the task finishes until this timer or the task is canceled.

Parameters:

Throws:


schedule

public void schedule(java.util.TimerTask task, long delay)

Schedules the task after the specified delay milliseconds for one time execution.

Parameters:

Throws:


schedule

public void schedule(java.util.TimerTask task, long delay, long period)

Schedules the task after the delay milliseconds and reschedules the task every period milliseconds after the last execution of the task finishes until this timer or the task is canceled.

Parameters:

Throws:


scheduleAtFixedRate

public void scheduleAtFixedRate(java.util.TimerTask task, java.util.Date date, long period)

Schedules the task at the specified date and reschedules the task at a fixed rate every period milliseconds until this timer or the task is canceled.

Parameters:

Throws:


scheduleAtFixedRate

public void scheduleAtFixedRate(java.util.TimerTask task, long delay, long period)

Schedules the task after the delay milliseconds and reschedules the task at a fixed rate every period milliseconds until this timer or the task is canceled.

Parameters:

Throws: