public static class ThreadPoolExecutor.DiscardOldestPolicy extends Object implements ThreadPoolExecutor.RejectedExecutionHandler
execute
, unless the executor
is shut down, in which case the task is discarded. This policy is
rarely useful in cases where other threads may be waiting for
tasks to terminate, or failures must be recorded. Instead consider
using a handler of the form:
new RejectedExecutionHandler() {
public void rejectedExecution(Runnable r, ThreadPoolExecutor e) {
Runnable dropped = e.getQueue().poll();
if (dropped instanceof Future<?>) {
((Future<?>)dropped).cancel(false);
// also consider logging the failure
}
e.execute(r); // retry
}}
Constructor and Description |
---|
ThreadPoolExecutor.DiscardOldestPolicy()
Creates a
DiscardOldestPolicy for the given executor. |
Modifier and Type | Method and Description |
---|---|
void |
rejectedExecution(Runnable r,
ThreadPoolExecutor e)
Obtains and ignores the next task that the executor
would otherwise execute, if one is immediately available,
and then retries execution of task r, unless the executor
is shut down, in which case task r is instead discarded.
|
public ThreadPoolExecutor.DiscardOldestPolicy()
DiscardOldestPolicy
for the given executor.public void rejectedExecution(Runnable r, ThreadPoolExecutor e)
rejectedExecution
in interface ThreadPoolExecutor.RejectedExecutionHandler
r
- the runnable task requested to be executede
- the executor attempting to execute this taskCopyright © 2000-2022 Apache Software Foundation. All Rights Reserved.