[SEDONA-187] Register UDAF function using Java

• Type: Improvement
• Status: Open
• Priority: Normal
• Resolution: Unresolved
• Fix Version/s: 1.2.1
• Labels: documentation newbie
• Assignee: Unassigned
• Reporter: Glauber M Dantas
• Created: 01/Nov/22 15:17
• Updated: 01/Nov/22 15:28

Description

I'm using Java and can register an UDF function, and it works:

UDF1<Geometry, String> stGetUTMZone = new StGetUTMZone();

sparkSession.udf().register("ST_GetUTMZone", stGetUTMZone, DataTypes.StringType);

However, when I try registering an UDAF function, besides no compilation error is found, I get a runtime error due to datatype mismatch:

import org.locationtech.jts.geom.Geometry;
import org.apache.spark.sql.Encoders;

sparkSession.udf().register("ST_Safe_Union_Aggr", functions.udaf(new StSafeUnionAggregator(), Encoders.javaSerialization(Geometry.class)));

Error: cannot resolve 'ST_Safe_Union_Aggr(geom)' due to data type mismatch: argument 1 requires binary type, however, 'filteredincomingdata.geom' is of array<tinyint> type.; line 1 pos 79;

Where geom is obtained through ST_GeomFromWKT().

I tried also using Encoders.kryo() and Encoders.bean() with no success.
 
I could not find any doc related to registering the UDAF function in Java using the new Aggreagtor<IN, BUF, OUT> that could use an Encoder compatible with Geometry used in Sedona.