Gracias a DontPanic:

 Schema timestampMilliType = LogicalTypes.timestampMillis().addToSchema(Schema.create(Schema.Type.LONG)); Schema schemaWithTimestamp = SchemaBuilder .record("MyRecord").namespace("org.demo") .fields() .name("timestamp_with_logical_type").type(timestampMilliType).noDefault() .name("timestamp_no_logical_type").type().longType().noDefault() .endRecord(); System.out.println(schemaWithTimestamp.toString(true));

Esto resulta en:

 { "type" : "record", "name" : "MyRecord", "namespace" : "org.demo", "fields" : [ { "name" : "timestamp_with_logical_type", "type" : { "type" : "long", "logicalType" : "timestamp-millis" } }, { "name" : "timestamp_no_logical_type", "type" : "long" } ] }

Gracias por la primera solución, ahora por tipo lógico anulable como:

 { "name":"maturityDate", "type":["null", { "type":"long","logicalType":"timestamp-millis" }] },

Calculo lo siguiente:

 Schema timestampMilliType = LogicalTypes.timestampMillis().addToSchema(Schema.create(Schema.Type.LONG)); Schema clientIdentifier = SchemaBuilder.record("ClientIdentifier") .namespace("com.baeldung.avro") .fields() .requiredString("hostName") .requiredString("ipAddress") .name("maturityDate") .type() .unionOf() .nullType() .and() .type(timestampMilliType) .endUnion() .noDefault() .endRecord();

Creo que puedes crear un esquema manualmente:

 List<Schema.Field> fields = new ArrayList<>(); Schema timeStampField = Schema.create(Schema.Type.LONG); fields.add(new Schema.Field("timestamp", LogicalTypes.timestampMillis().addToSchema(timeStampField), null, null)); Schema resultSchema = Schema.createRecord("MyRecord", null, "org.demo", false, fields); System.out.println(resultSchema);

tu esquema:

 {"type":"record","name":"MyRecord","namespace":"org.demo","fields":[{"name":"timestamp","type":"long"}]}

esquema de resultado con marca de tiempoMillis:

 {"type":"record","name":"MyRecodr","namespace":"org.demo","fields":[{"name":"timestamp","type":{"type":"long","logicalType":"timestamp-millis"}}]}