JavaConversions API 'null' bug

nullbug.scala

/*
 * This demonstrates a bug that occurs in the collections `JavaConversions` API.
 * This is __not__ a bug with the type system.
 *
 * The conversions API does not consider that it could potentially try to convert a `null` value 
 * that has been cast as java collection to a scala collection. Being that conversion procedures
 * potentially involve calling functions upon the underlying collection __in order__ to achieve conversion
 * it is not possible for the caller to simply perform a check against the converted collection to see if it
 * is null, as the VM will throw a NullPointerException when any access is attempted to the underlying
 * java collection (which is really a null reference)
 *
 * This was noticed and tested with Scala 2.11.4
 * */
 
 import java.util.{List => JList}
 import scala.collection.JavaConversions._
 
 val badList: JList[String] /* Content type does not matter */ = null.asInstanceOf[JList[String]]
 val badSeq: Seq[String] = badList // The compiler will wrap this with a converter. Invocation of the converter will lead to the exception.