I m trying to do a Kafka tutorial in Kotlin and wondered wha

Question

I m trying to do a Kafka tutorial in Kotlin and wondered what the following code is in idiomatic Kotlin ``` send data asynchronous producer send record new Callback public void onCompletion RecordMetadata recordMetadata Exception e executes every time a record is successfully sent or an exception is thrown if e == null the record was successfully sent <http logger info|logger info> Received new metadata n + Topic + recordMetadata topic + n + Partition + recordMetadata partition + n + Offset + recordMetadata offset + n + Timestamp + recordMetadata timestamp else logger error Error while producing e ```

waltermcq · Answer

Copy pasting this code into IntelliJ and letting it do the Kotlin conversion yields something that is broken

waltermcq · Answer

It has been long since I did any Java but it looks like Callback is being extended with an implementation of onCompletion i e anonymous class

waltermcq · Answer

Would it make sense to use an extension function on Callback here `fun Callback onCompletion recordMetadata RecordMetadata e Exception `

akatkov · Answer

``` send data asynchronous producer send record object Callback fun onCompletion recordMetadata RecordMetadata e Exception executes every time a record is successfully sent or an exception is thrown if e == null the record was successfully sent <http logger info|logger info> Received new metadata n + Topic + recordMetadata topic + n + Partition + recordMetadata partition + n + Offset + recordMetadata offset + n + Timestamp + recordMetadata timestamp else logger error Error while producing e ```

akatkov · Answer

i believe that should be valid and does the same as the java version with creating an anonymous class might need an override on the `fun onCompletion`

waltermcq · Answer

I see you used the object keyword above

waltermcq · Answer

waltermcq · Answer

ok that creates an anonymous inner class

waltermcq · Answer

I ll try this out

waltermcq · Answer

Seems to work Thanks < akatkov> My next step was to try the nested class object keyword

waltermcq · Answer

You beat me to it slightly smiling face