flinksqlbug : AggregateFunction udf Could not extract a data type from

org.apache.flink.table.api.ValidationException: SQL validation failed. An error occurred in the type inference logic of function ‘default_catalog.default_database.CollectSetSort’.
org.apache.flink.table.api.ValidationException: An error occurred in the type inference logic of function ‘default_catalog.default_database.CollectSetSort’.
org.apache.flink.table.api.ValidationException: Could not extract a valid type inference for function class ‘com.xiaomi.cloud.streaming.computing.udagg.CollectSetSort’. Please check for implementation mistakes and/or provide a corresponding hint.
org.apache.flink.table.api.ValidationException: Error in extracting a signature to accumulator mapping.
org.apache.flink.table.api.ValidationException: Unable to extract a type inference from method:
public void com.xiaomi.cloud.streaming.computing.udagg.CollectSetSort.accumulate(java.util.ArrayList,java.lang.Integer)
org.apache.flink.table.api.ValidationException: Could not