public R getResult() {
        return result;
    }
Returns the result of executing the query on one partition. The result type is determined by
the query. Note: queries may choose to return {@code null} for a successful query, so {@link
this#isSuccess()} and {@link this#isFailure()} must be used to determine whether the query
was successful of failed on this partition.

@throws IllegalArgumentException if this is not a successful query.
streams/src/main/java/org/apache/kafka/streams/query/internals/SucceededQueryResult.java