Runnable
public abstract class TimerTask extends Object implements Runnable
Timer
.
A timer task is not reusable. Once a task has been scheduled
for execution on a Timer
or cancelled, subsequent attempts to
schedule it for execution will throw IllegalStateException
.
Modifier | Constructor | Description |
---|---|---|
protected |
TimerTask() |
Creates a new timer task.
|
Modifier and Type | Method | Description |
---|---|---|
boolean |
cancel() |
Cancels this timer task.
|
abstract void |
run() |
The action to be performed by this timer task.
|
long |
scheduledExecutionTime() |
Returns the scheduled execution time of the most recent
actual execution of this task.
|
public abstract void run()
run
in interface Runnable
Thread.run()
public boolean cancel()
Note that calling this method from within the run
method of
a repeating timer task absolutely guarantees that the timer task will
not run again.
This method may be called repeatedly; the second and subsequent calls have no effect.
true
if it prevents one or more scheduled
executions from taking place.)public long scheduledExecutionTime()
This method is typically invoked from within a task's run method, to determine whether the current execution of the task is sufficiently timely to warrant performing the scheduled activity:
public void run() {
if (System.currentTimeMillis() - scheduledExecutionTime() >=
MAX_TARDINESS)
return; // Too late; skip this execution.
// Perform the task
}
This method is typically not used in conjunction with
fixed-delay execution repeating tasks, as their scheduled
execution times are allowed to drift over time, and so are not terribly
significant.Date.getTime()
Submit a bug or feature
For further API reference and developer documentation, see Java SE Documentation. That documentation contains more detailed, developer-targeted descriptions, with conceptual overviews, definitions of terms, workarounds, and working code examples.
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DRAFT 9-internal+0-adhoc.mlchung.jdk9-jdeps