Fixed document mistake and fit for 5.1.1 API

Author: Rui Hu

docs/java-api/docs/index_.asciidoc

@@ -156,8 +156,8 @@ String _type = response.getType();
 String _id = response.getId();
 // Version (if it's the first time you index this document, you will get: 1)
 long _version = response.getVersion();
-// isCreated() is true if the document is a new one, false if it has been updated
-boolean created = response.isCreated();
+// status has stored current instance statement.
+RestStatus status = response.status();
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 For more information on the index operation, check out the REST