src/Pure/System/cygwin.scala

 Accessing the Cygwin installation.
 */
 
 package isabelle
 
+import java.lang.System
 import java.lang.reflect.Method
 import java.io.File
 import java.net.URL
 import java.awt.Component
 

       error("Bad Cygwin installation: " + root.toString)
   }
 
   def check_root(): String =
   {
-    val this_cygwin = java.lang.System.getenv("THIS_CYGWIN")
+    val this_cygwin = System.getenv("THIS_CYGWIN")
     val root =
       if (this_cygwin != null && this_cygwin != "") this_cygwin
       else
         query_registry(CYGWIN_SETUP1, "rootdir") orElse
         query_registry(CYGWIN_SETUP2, "rootdir") getOrElse