WARNING: Deprecated in 7.15.0.
The Java REST Client is deprecated in favor of the Java API Client.
ClearIndicesCacheRequest can be applied to one or more indices, or even on
_all the indices:
When executing a
ClearIndicesCacheRequest in the following manner, the client waits
ClearIndicesCacheResponse to be returned before continuing with code execution:
ClearIndicesCacheResponse clearCacheResponse = client.indices().clearCache(request, requestOptions);
Synchronous calls may throw an
IOException in case of either failing to
parse the REST response in the high-level REST client, the request times out
or similar cases where there is no response coming back from the server.
In cases where the server returns a
5xx error code, the high-level
client tries to parse the response body error details instead and then throws
ElasticsearchException and adds the original
ResponseException as a
suppressed exception to it.
ClearIndicesCacheRequest can also be done in an asynchronous fashion so that
the client can return directly. Users need to specify how the response or
potential failures will be handled by passing the request and a listener to the
asynchronous clear-cache method:
The asynchronous method does not block and returns immediately. Once it is
ActionListener is called back using the
if the execution successfully completed or using the
onFailure method if
it failed. Failure scenarios and expected exceptions are the same as in the
synchronous execution case.
A typical listener for
clear-cache looks like:
ClearIndicesCacheResponse allows to retrieve information about the
executed operation as follows:
Total number of shards hit by the clear cache request
Number of shards where the clear cache has succeeded
Number of shards where the clear cache has failed
A list of failures if the operation failed on one or more shards
By default, if the indices were not found, an
ElasticsearchException will be thrown: