Question: This about running Spark/Scala from a Zeppelin notebook.

In order to better modularize and reorganize code, I need to import existing Scala classes, packages or functions into the notebook, preferably skipping creating a jar file (much the same as in PySpark). 

Something like:

```
import myclass

```

where 'myclass' is implemented in a .scala file. Probably this source code needs to reside in a specific location for Zeppelin.

Answer: 
Primary technical reason is that Spark depends heavily on direct access to native memory with `sun.misc.Unsafe`, which has been made private in Java 9.

* <https://issues.apache.org/jira/browse/SPARK-24421>
* <http://apache-spark-developers-list.1001551.n3.nabble.com/Java-9-td20875.html>
Spark depends on the memory API's which has been changed in JDK 9 so it is not available starting JDK 9.

And that is the reason for this.

Please check the issue:

<https://issues.apache.org/jira/browse/SPARK-24421>