Java FutureTask Methods Explained

Common methods of FutureTask include:

1. get(): obtain the result of a task, and if the task is not yet completed, wait until it is finished before returning the result.
2. Retrieve the result of the task, waiting a specified amount of time determined by the timeout and unit parameters. If the task completes within the specified time, return the result; otherwise, throw a TimeoutException.
3. cancel(boolean mayInterruptIfRunning): Attempt to cancel the execution of a task. If the task has already been completed or canceled, this method returns false; if the task has not yet started, it will attempt to cancel the execution of the task and return true; if the task is currently running and the mayInterruptIfRunning parameter is true, it will interrupt the execution of the task and return true; if the task is currently running and the mayInterruptIfRunning parameter is false, it is unable to cancel the execution of the task and returns false.
4. isCancellationRequested(): Determine if the task has been cancelled.
5. isDone(): check if the task has been completed.
6. run(): Execute the task. This method is called when the task has not been executed yet.
7. runAndReset(): Execute the task and reset its status. This method is called before the task is executed and resets the task’s status after completion, allowing it to be run again.
8. set the result of the task and mark it as completed.
9. setException(Throwable throwable): Set the exception thrown during task execution and mark the task as complete.
10. isPeriodic() checks if the task is a periodic task. This method is not specifically implemented in FutureTask, but instead in ScheduledFutureTask.