[[breaking_60_java_changes]] === Java API changes ==== `setSource` methods require XContentType Previously the `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. ==== `DeleteByQueryRequest` requires an explicitly set query 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. ==== `InternalStats` and `Stats` getCountAsString() method removed The `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 ==== `ActionRequestBuilder#execute` returns `ActionFuture` rather than `ListenableActionFuture` 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.