setSource methods and other methods that accepted byte/string representations of
an object source did not require the XContentType to be specified. The auto-detection of the content
type is no longer used, so these methods now require the XContentType as an additional argument when
providing the source in bytes or as a string.
In previous versions of Elasticsearch, delete by query requests without an explicit query
were accepted, match_all was used as the default query and all documents were deleted
as a result. From version 6.0.0, a
DeleteByQueryRequest requires an explicit query be set.
count value in the stats aggregation represents a doc count that shouldn’t require a formatted
version. This method was deprecated in 5.4 in favour of just using
String.valueOf(getCount()) if needed
When sending a request through the request builders e.g. client.prepareSearch().execute(), it used to
be possible to call
addListener against the returned
ListenableActionFuture. With this change an
ActionFuture is returned instead, which is consistent with what the
Client methods return, hence
it is not possible to associate the future with listeners. The
execute method that accept a listener
as an argument can be used instead.
date_histogram aggregation code has been refactored to use common
code for ordering buckets. The
BucketOrder class must be used instead of
static methods in the
BucketOrder class must be called instead of directly
accessing internal order instances, e.g.
BucketOrder.key(boolean) to order the
terms aggregation buckets by