diff -r 2c585bb9560c -r 995162143ef4 src/Pure/PIDE/xml.scala --- a/src/Pure/PIDE/xml.scala Thu Feb 20 14:17:28 2014 +0100 +++ b/src/Pure/PIDE/xml.scala Thu Feb 20 14:36:17 2014 +0100 @@ -7,6 +7,7 @@ package isabelle + import java.util.WeakHashMap import java.lang.ref.WeakReference import javax.xml.parsers.DocumentBuilderFactory