Details
Major Description
Similar to SPARK-32238, the use of java.lang.Class.getSimpleName in TreeNode.nodeName is problematic because Scala classes may trigger java.lang.InternalError: Malformed class name.
This happens more often when using nested classes in Scala (or declaring classes in Scala REPL which implies class nesting).
Note that on newer versions of JDK the underlying malformed class name no longer reproduces, so it's less of an issue there. But on JDK8u this problem still exists so we still have to fix it.
