Hi Timo, But getResultType should only return a concrete type information, right? How could I implement with a generic type?
I'd like to clarify my questions again. Say I want to implement my own "MAX" function, but I want to apply it to different types, e.g. integer, long, double etc, so I tried to write a class which extends AggregateFunction *with generic type* to implement the max function. Then I want to register only one function name for all types. E.g. tableEnv.registerFunction("MYMAX", new MyMax()); instead of tableEnv.registerFunction("MYINTEGERMAX", new MyIntegerMax()); tableEnv.registerFunction("MYLONGMAX", new MyLongMax()); tableEnv.registerFunction("MYDOULBEMAX", new MyDoubleMax()); Is there a way to implement that? I know the build in function "MAX" can apply to all types, so I wonder if I can also implement that. Thanks. -- Sent from: http://apache-flink-user-mailing-list-archive.2336050.n4.nabble.com/