[Feature Request]: UDF supports lambda & RecordType parameter

[gabrywu]

What would you like to happen?

I want to create a new UDF which supports a lambda parameter and a Row parameter, for example

static class LambdaUDFA implements BeamSqlUdf {
        public static List<Row> eval(@Parameter(name = "rows") List<Row> rows,
                                     @Parameter(name = "filter") Predicate1<Row> filter) {
            return rows.stream().filter(filter::apply).collect(Collectors.toList());
        }
    }

But beam SQL throws an exception like this
sun.reflect.generics.reflectiveObjects.ParameterizedTypeImpl cannot be cast to java.lang.Class

Issue Priority

Priority: 2 (default / most feature requests should be filed as P2)

Issue Components

• Component: Python SDK
• Component: Java SDK
• Component: Go SDK
• Component: Typescript SDK
• Component: IO connector
• Component: Beam examples
• Component: Beam playground
• Component: Beam katas
• Component: Website
• Component: Spark Runner
• Component: Flink Runner
• Component: Samza Runner
• Component: Twister2 Runner
• Component: Hazelcast Jet Runner
• Component: Google Cloud Dataflow Runner

[Amar3tto]

There are some difficulties in supporting UDFs with @Parameter(...) Row and @Parameter(...) Predicate1:

1. Each parameter type should be translatable to Calcite RelDataType.
2. If we want to translate Row type to Calcite RelRecordType, then we need to have an ability to somehow pass a Schema of that Row. This is currently not implemented in registering UDFs.
3. There is no an appropriate Calcite RelDataType for lambda types.
4. At the moment when UDF is applied, we have all Rows in form of Object[]. And Object[] cannot be automatically cast to Row.

[Amar3tto]

@gabrywu FYI