src/Tools/jEdit/src-base/pide_docking_framework.scala

 package isabelle.jedit_base
 
 
 import isabelle._
 
+import java.util.{List => JList}
 import java.awt.event.{ActionListener, ActionEvent}
 import javax.swing.{JPopupMenu, JMenuItem}
 
 import org.gjt.sp.jedit.View
 import org.gjt.sp.jedit.gui.{DockableWindowManagerProvider, DockableWindowFactory,

               case dockable: Dockable => dockable.detach_operation
               case _ => None
             }
 
           case panel: PanelWindowContainer =>
-            val entries = Untyped.get[java.util.List[AnyRef]](panel, "dockables").toArray
+            val entries = Untyped.get[JList[AnyRef]](panel, "dockables").toArray
             val wins =
               (for {
                 entry <- entries.iterator
                 if Untyped.get[String](Untyped.get(entry, "factory"), "name") == dockable_name
                 win = Untyped.get[Any](entry, "win")