in flink-connector-mongodb/src/main/java/org/apache/flink/connector/mongodb/table/converter/BsonToRowDataConverters.java [417:425]
private static String convertToString(BsonValue bsonValue) {
if (bsonValue.isString()) {
return bsonValue.asString().getValue();
}
if (bsonValue.isObjectId()) {
return bsonValue.asObjectId().getValue().toHexString();
}
return new BsonDocument(ENCODE_VALUE_FIELD, bsonValue).toJson(DEFAULT_JSON_WRITER_SETTINGS);
}