[[java-rest-high-watcher-ack-watch]]
=== Ack Watch API

[[java-rest-high-watcher-ack-watch-execution]]
==== Execution

{xpack-ref}/actions.html#actions-ack-throttle[Acknowledging a watch] enables you
to manually throttle execution of a watch's actions. A watch can be acknowledged
through the following request:

["source","java",subs="attributes,callouts,macros"]
--------------------------------------------------
include-tagged::{doc-tests}/WatcherDocumentationIT.java[ack-watch-execute]
--------------------------------------------------
<1> The ID of the watch to ack.
<2> An optional list of IDs representing the watch actions that should be acked.
If no action IDs are provided, then all of the watch's actions will be acked.

[[java-rest-high-watcher-ack-watch-response]]
==== Response

The returned `AckWatchResponse` contains the new status of the requested watch:

["source","java",subs="attributes,callouts,macros"]
--------------------------------------------------
include-tagged::{doc-tests}/WatcherDocumentationIT.java[ack-watch-response]
--------------------------------------------------
<1> The status of a specific action that was acked.
<2> The acknowledgement state of the action. If the action was successfully
acked, this state will be equal to `AckStatus.State.ACKED`.

[[java-rest-high-watcher-ack-watch-async]]
==== Asynchronous Execution

This request can be executed asynchronously:

["source","java",subs="attributes,callouts,macros"]
--------------------------------------------------
include-tagged::{doc-tests}/WatcherDocumentationIT.java[ack-watch-execute-async]
--------------------------------------------------
<1> The `AckWatchRequest` to execute and the `ActionListener` to use when
the execution completes.

The asynchronous method does not block and returns immediately. Once the request
completes, the `ActionListener` is called back using the `onResponse` method
if the execution successfully completed or using the `onFailure` method if
it failed.

A listener for `AckWatchResponse` can be constructed as follows:

["source","java",subs="attributes,callouts,macros"]
--------------------------------------------------
include-tagged::{doc-tests}/WatcherDocumentationIT.java[ack-watch-execute-listener]
--------------------------------------------------
<1> Called when the execution is successfully completed. The response is
provided as an argument.
<2> Called in case of failure. The raised exception is provided as an argument.