Package org.elasticsearch.tasks

Class CancellableTasksTracker<T>

java.lang.Object

org.elasticsearch.tasks.CancellableTasksTracker<T>

public class CancellableTasksTracker<T>
extends Object

Tracks items that are associated with cancellable tasks, supporting efficient lookup by task ID and by parent task ID

Constructor Summary

Constructors

Constructor	Description
CancellableTasksTracker(T[] empty)

Method Summary

Modifier and Type	Method	Description
T	get(long id)	Get the item that corresponds with the given task, or null if there is no such item.
Stream<T>	getByParent(TaskId parentTaskId)	Return a collection of all the tracked items with a given parent, which will include at least every item for which put(org.elasticsearch.tasks.Task, T) completed, but remove(org.elasticsearch.tasks.Task) hasn't started.
void	put(Task task, T item)	Add an item for the given task.
T	remove(Task task)	Remove (and return) the item that corresponds with the given task.
Collection<T>	values()	Return a collection of all the tracked items.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

CancellableTasksTracker

public CancellableTasksTracker(T[] empty)

Method Details

put

public void put(Task task,
 T item)

Add an item for the given task. Should only be called once for each task, and item must be unique per task too.

get

public T get(long id)

Get the item that corresponds with the given task, or null if there is no such item.

remove

public T remove(Task task)

Remove (and return) the item that corresponds with the given task. Return null if not present. Safe to call multiple times for each task. However, getByParent(org.elasticsearch.tasks.TaskId) may return this task even after a call to this method completes, if the removal is actually being completed by a concurrent call that's still ongoing.

values

public Collection<T> values()

Return a collection of all the tracked items. May be large. In the presence of concurrent calls to put(org.elasticsearch.tasks.Task, T) and remove(org.elasticsearch.tasks.Task) it behaves similarly to ConcurrentHashMap.values().

getByParent

public Stream<T> getByParent(TaskId parentTaskId)

Return a collection of all the tracked items with a given parent, which will include at least every item for which put(org.elasticsearch.tasks.Task, T) completed, but remove(org.elasticsearch.tasks.Task) hasn't started. May include some additional items for which all the calls to remove(org.elasticsearch.tasks.Task) that started before this method was called have not completed.