[AVRO-2194] GenericRecord and specific class return different java type for the same field with logicalType

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 1.8.2
• Component/s: java, logical types
• Assignee: Unassigned
• Reporter: Eva Krejcirova
• Created: 26/Jun/18 14:47
• Updated: 27/Jun/18 13:35

Description

I have an Avro schema which contains field with logical type timestamp-millis. When I deserialize  an object with this schema from json to GenericRecord, I get Long as type of this field. When I deserialize it to specific class, I get DateTime. This prevents me to write a generic code which would handle both cases (I would expect this to be possible since the generated class implements GenericRecord interface).

E.g.

final GenericRecord timestampGenericRecord = readJsonGeneric("timestamptest.json", schema);
final TimestampTest timestampTestIn = readJson("timestamptest.json", timestampTestOut.getClass(), schema);

System.out.println("------------ Generic record --------------");
printTimestamp(timestampGenericRecord);

System.out.println("------------ Specific record --------------");
printTimestamp(timestampTestIn);

----

private static void printTimestamp(GenericRecord record) {
   System.out.println(record);
   System.out.println(record.get("timestampDateTime").getClass());
}

prints out:

------------ Generic record --------------
{"timestampLong": 1530023620474, "timestampDateTime": 1530023620478}
class java.lang.Long
------------ Specific record --------------
{"timestampLong": 1530023620474, "timestampDateTime": 2018-06-26T14:33:40.478Z}
class org.joda.time.DateTime

I am attaching sample code which demonstrates the problem.