Flink 1.9 SQL Kafka Connector，Json format，how to deal with not json message?

[LakeShen]

Hi community,when I write the flink ddl sql like this:

CREATE TABLE kafka_src (
  id varchar,
  a varchar,
  b TIMESTAMP,
  c TIMESTAMP
)
  with (
   ...
    'format.type' = 'json',
    'format.property-version' = '1',
    'format.derive-schema' = 'true',
    'update-mode' = 'append'
);

If the message is not the json format ,there is a error in the log。
My question is that how to deal with the message which it not json format?
My thought is that I can catch the exception
in JsonRowDeserializationSchema deserialize() method,is there any
parameters to do this?
Thanks your replay.