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 and Type | Field and Description |
|---|---|
| pack-priv static final int | CANCELLED
This task has been cancelled (with a call to TimerTask.cancel). |
| pack-priv static final int | EXECUTED
This non-repeating task has already executed (or is currently executing) and has not been cancelled. |
| pack-priv final Object | lock
This object is used to control access to the TimerTask internals. |
| pack-priv long | nextExecutionTime
Next execution time for this task in the format returned by System.currentTimeMillis, assuming this task is scheduled for execution. |
| pack-priv long | period
Period in milliseconds for repeating tasks. |
| pack-priv static final int | SCHEDULED
This task is scheduled for execution. |
| pack-priv int | state
The state of this task, chosen from the constants below. |
| pack-priv static final int | VIRGIN
This task has not yet been scheduled. |
| Access | Constructor and Description |
|---|---|
| protected |
| Modifier and Type | Method and Description |
|---|---|
| public boolean | Returns: true if this task is scheduled for one-time execution and has not yet run, or this task is scheduled for repeated execution. Returns false if the task was scheduled for one-time execution and has already run, or if the task was never scheduled, or if the task was already cancelled. (Loosely speaking, this method returnstrue if it prevents one or more scheduled
executions from taking place.)Cancels this timer task. |
| public abstract void | |
| public long | Returns: the time at which the most recent execution of this task was scheduled to occur, in the format returned by Date.getTime(). The return value is undefined if the task has yet to commence its first execution.Returns the scheduled execution time of the most recent actual execution of this task. |
| CANCELLED | back to summary |
|---|---|
| pack-priv static final int CANCELLED This task has been cancelled (with a call to TimerTask.cancel). | |
| EXECUTED | back to summary |
|---|---|
| pack-priv static final int EXECUTED This non-repeating task has already executed (or is currently executing) and has not been cancelled. | |
| lock | back to summary |
|---|---|
| pack-priv final Object lock This object is used to control access to the TimerTask internals. | |
| nextExecutionTime | back to summary |
|---|---|
| pack-priv long nextExecutionTime Next execution time for this task in the format returned by System.currentTimeMillis, assuming this task is scheduled for execution. For repeating tasks, this field is updated prior to each task execution. | |
| period | back to summary |
|---|---|
| pack-priv long period Period in milliseconds for repeating tasks. A positive value indicates fixed-rate execution. A negative value indicates fixed-delay execution. A value of 0 indicates a non-repeating task. | |
| SCHEDULED | back to summary |
|---|---|
| pack-priv static final int SCHEDULED This task is scheduled for execution. If it is a non-repeating task, it has not yet been executed. | |
| state | back to summary |
|---|---|
| pack-priv int state The state of this task, chosen from the constants below. | |
| VIRGIN | back to summary |
|---|---|
| pack-priv static final int VIRGIN This task has not yet been scheduled. | |
| TimerTask | back to summary |
|---|---|
| protected TimerTask() Creates a new timer task. | |
| cancel | back to summary |
|---|---|
| public boolean cancel() Cancels this timer task. If the task has been scheduled for one-time execution and has not yet run, or has not yet been scheduled, it will never run. If the task has been scheduled for repeated execution, it will never run again. (If the task is running when this call occurs, the task will run to completion, but will never run again.) Note that calling this method from within the This method may be called repeatedly; the second and subsequent calls have no effect.
| |
| run | back to summary |
|---|---|
| public abstract void run() Redeclares java. The action to be performed by this timer task. | |
| scheduledExecutionTime | back to summary |
|---|---|
| public long scheduledExecutionTime() Returns the scheduled execution time of the most recent actual execution of this task. (If this method is invoked while task execution is in progress, the return value is the scheduled execution time of the ongoing task execution.) 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:
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.
| |