How to convert to avro data to date

I have an avro schema as per below...

 "namespace": "example.avro",
 "type": "record",
 "name": "UserDate",
 "fields": [
     {"name": "name", "type": "string"},         
	 {"name": "date", "type": [{"type":"int","logicalType":"date"}, "null"]},
     {"name": "datenotnullable", "type": {"type":"string","logicalType":"date"}}	 
 ]

When I retrieve the avro data, I plan to detect the logicalType and then do the conversion to date if the logicalType is "date"

How do I go about and achieve this?

    DatumReader<GenericRecord> datumReader = new GenericDatumReader<GenericRecord>(schema);
    GenericRecord user = null;
    try(DataFileReader<GenericRecord> dataFileReader = new DataFileReader<GenericRecord>(file, 
      datumReader)){
    while (dataFileReader.hasNext()) {

    user = dataFileReader.next(user);
  }
}

The data coming from above code is still the original primitive type.

I am not sure how to have this data as per defined logicalType?

From reading, I think somehow I need to implement Conversion, but not sure how to do this...

Any help?

I found the answer here https://stackoverflow.com/a/52041154/3663854

Modifying my code as per below, it work

    final GenericData genericData = new GenericData();
    genericData.addLogicalTypeConversion(new MyTimestampConversion());
    DatumReader<GenericRecord> datumReader = new GenericDatumReader<GenericRecord>(schema1, schema1, genericData);
    //DatumReader<GenericRecord> datumReader = new GenericDatumReader<GenericRecord>(schema); //original code
    
    File file2 = new File("long.avro");

    GenericRecord user = null;
    
    try(DataFileReader<GenericRecord> dataFileReader = new DataFileReader<GenericRecord>(file, datumReader)){
        while (dataFileReader.hasNext()) {

            user = dataFileReader.next(user);
        }
    }

Added Conversion

public static class MyTimestampConversion extends Conversion<String> {
    public MyTimestampConversion() {
    }

    public Class<String> getConvertedType() {
        return String.class;
    }

    public String getLogicalTypeName() {
        return "timestamp-millis";
    }

    public String fromLong(Long millisFromEpoch, Schema schema, LogicalType type) {
        return (new DateTime(millisFromEpoch, DateTimeZone.UTC)).toString();
    }

    public Long toLong(String timestamp, Schema schema, LogicalType type) {
        return new Long(timestamp);
    }

    public String fromCharSequence(CharSequence value, Schema schema, LogicalType type) {
        return (new DateTime(value, DateTimeZone.UTC)).toString();
    }

    public CharSequence toCharSequence(String value, Schema schema, LogicalType type) {
        return value;
    }
}

Result (original, not working)

{"DateModified": 520171631042}
{"DateModified": 0}

Result (current, working)

{"DateModified": "1986-06-26T12:07:11.042Z"}
{"DateModified": "1970-01-01T00:00:00.000Z"}