Class cast exception on (CompoundEdit) UndoableEditEvent.getEdit()

FULL PRODUCT VERSION :
java version "9.0.1"
Java(TM) SE Runtime Environment (build 9.0.1+11)
Java HotSpot(TM) 64-Bit Server VM (build 9.0.1+11, mixed mode)

ADDITIONAL OS VERSION INFORMATION :
Microsoft Windows [Version 10.0.15063]

A DESCRIPTION OF THE PROBLEM :

Exception in thread "AWT-EventQueue-0" java.lang.ClassCastException: java.desktop/javax.swing.text.AbstractDocument$DefaultDocumentEventUndoableWrapper cannot be cast to java.desktop/javax.swing.undo.CompoundEdit
at CompoundEdit edit = (CompoundEdit) undoableEditEvent.getEdit();

Caused by addition of DefaultDocumentEventUnoableWrapper instead of DefaultDocumentEvent in javax.swing.text.AbstractDocument.java


REGRESSION. Last worked in version 8u151

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
1. Extend javax.swing.undo.UndoManager

2. Override public void undoableEditHappened(UndoableEditEvent e):
 
   javax.swing.undo.CompoundEdit edit = (javax.swing.undo.CompoundEdit)
   undoableEditEvent.getEdit();

3. Compile and execute



EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
No class cast exception in undoableEditHappened
ACTUAL -
Exception in thread "AWT-EventQueue-0" java.lang.ClassCastException: java.desktop/javax.swing.text.AbstractDocument$DefaultDocumentEventUndoableWrapper cannot be cast to java.desktop/javax.swing.undo.CompoundEdit

at CompoundEdit edit = (CompoundEdit) undoableEditEvent.getEdit();

REPRODUCIBILITY :
This bug can be reproduced always.

CUSTOMER SUBMITTED WORKAROUND :
None

I've seen this bug mentioned in another bug database but not here, so I'm writing this bug report in hopes that it will be fixed