Java support

[jonathanindig]

Some Java libraries take in POJOs for ser/de, etc.

It would be easier to work with those libraries if we could define POJOs in Polynote (instead of Scala classes).

[sjparsons]

I'm on a team that uses Java for interacting with Spark and I'd like the ability to run Java code in a notebook. What are the blockers that prevent using Java in a notebook?

[jonathanindig]

Welcome, @sjparsons! Thanks for your interest in Polynote :)

Java is definitely high on the list of new languages we'd like to add, but we just haven't gotten there yet.

We're planning to add some rough developer documentation soon, but the main part of adding a new language is implementing this interface: https://github.com/polynote/polynote/blob/master/polynote-kernel/src/main/scala/polynote/kernel/interpreter/Interpreter.scala

A PR would be most welcome!

[davidpham87]

Once we get Java, I guess all other JVM language could be integrated as well (e.g Clojure)?

[seralf]

Some Java libraries take in POJOs for ser/de, etc.

It would be easier to work with those libraries if we could define POJOs in Polynote (instead of Scala classes).

a partial workaround when using Java libraries requiring POJO from Scala is the usage of annotation for classes (please ignore this comment if you already mentioned it):
https://alvinalexander.com/scala/scala-javabeans-beanproperty-annotation
anyway is quite annoying to write classes like this, especially case classes, as it introduces a lot of boilerplate code... my solution in some case was to actually duplicate the model, and provide the beans by requests, but it's not always possible.