How to extract error root cause reason using Java RestHighLevelClient?

[Nishikant_Tayade]

Hi,

I am trying to perform a wildcard query on date type, which is not allowed by ES, so I see an exception being thrown from ES as below:

{
  "error": {
    "root_cause": [
      {
        "type": "query_shard_exception",
        "reason": "Can only use wildcard queries on keyword, text and wildcard fields - not on [OrderDate] which is of type [date]",
        "index_uuid": "cypJ5a9eTlmGhQkJy_BJAQ",
        "index": "order_202109"
      }
    ],
    "type": "search_phase_execution_exception",
    "reason": "all shards failed",
    "phase": "query",
    "grouped": true,
    "failed_shards": [
      {
        "shard": 0,
        "index": "order_202109",
        "node": "TkkTI0EhTsC2_5QxtzN0Rw",
        "reason": {
          "type": "query_shard_exception",
          "reason": "Can only use wildcard queries on keyword, text and wildcard fields - not on [OrderDate] which is of type [date]",
          "index_uuid": "cypJ5a9eTlmGhQkJy_BJAQ",
          "index": "order_202109"
        }
      }
    ]
  },
  "status": 400
}

But when I get the rootCause from ElasticsearchException

Throwable cause = ElasticsearchException.getRootCause();
cause.getMessage();

It only gives me

 "type": "search_phase_execution_exception",
 "reason": "all shards failed",

Is there any utility method to extract the actual error root cause, which is

 "type": "query_shard_exception",
  "reason": "Can only use wildcard queries on keyword, text and wildcard fields - not on [OrderDate] which is of type [date]"

Thank you:)