diff --git a/src/Tools/jEdit/jedit_main/scala_console.scala b/src/Tools/jEdit/jedit_main/scala_console.scala
--- a/src/Tools/jEdit/jedit_main/scala_console.scala
+++ b/src/Tools/jEdit/jedit_main/scala_console.scala
@@ -1,182 +1,182 @@
 /*  Title:      Tools/jEdit/jedit_main/scala_console.scala
     Author:     Makarius
 
 Scala instance of Console plugin.
 */
 
 package isabelle.jedit_main
 
 
 import isabelle._
 import isabelle.jedit._
 
 import console.{Console, ConsolePane, Shell, Output}
 import org.gjt.sp.jedit.JARClassLoader
 import java.io.{OutputStream, Writer, PrintWriter}
 
 
 class Scala_Console extends Shell("Scala")
 {
   /* global state -- owned by GUI thread */
 
   @volatile private var interpreters = Map.empty[Console, Interpreter]
 
   @volatile private var global_console: Console = null
   @volatile private var global_out: Output = null
   @volatile private var global_err: Output = null
 
   private val console_stream = new OutputStream
   {
     val buf = new StringBuilder(100)
 
     override def flush(): Unit =
     {
       val s = buf.synchronized { val s = buf.toString; buf.clear(); s }
       val str = UTF8.decode_permissive(s)
       GUI_Thread.later {
-        if (global_out == null) System.out.print(str)
+        if (global_out == null) java.lang.System.out.print(str)
         else global_out.writeAttrs(null, str)
       }
       Time.seconds(0.01).sleep()  // FIXME adhoc delay to avoid loosing output
     }
 
     override def close(): Unit = flush()
 
     def write(byte: Int): Unit =
     {
       val c = byte.toChar
       buf.synchronized { buf.append(c) }
       if (c == '\n') flush()
     }
   }
 
   private val console_writer = new Writer
   {
     def flush(): Unit = console_stream.flush()
     def close(): Unit = console_stream.flush()
 
     def write(cbuf: Array[Char], off: Int, len: Int): Unit =
     {
       if (len > 0) {
         UTF8.bytes(new String(cbuf.slice(off, off + len))).foreach(console_stream.write(_))
       }
     }
   }
 
   private def with_console[A](console: Console, out: Output, err: Output)(e: => A): A =
   {
     global_console = console
     global_out = out
     global_err = if (err == null) out else err
     try {
       scala.Console.withErr(console_stream) {
         scala.Console.withOut(console_stream) { e }
       }
     }
     finally {
       console_stream.flush
       global_console = null
       global_out = null
       global_err = null
     }
   }
 
   private def report_error(str: String): Unit =
   {
     if (global_console == null || global_err == null) isabelle.Output.writeln(str)
     else GUI_Thread.later { global_err.print(global_console.getErrorColor, str) }
   }
 
 
   /* interpreter thread */
 
   private abstract class Request
   private case class Start(console: Console) extends Request
   private case class Execute(console: Console, out: Output, err: Output, command: String)
     extends Request
 
   private class Interpreter
   {
     private val running = Synchronized[Option[Thread]](None)
     def interrupt(): Unit = running.change(opt => { opt.foreach(_.interrupt()); opt })
 
     private val interp =
       Scala.Compiler.context(error = report_error, jar_dirs = JEdit_Lib.directories).
         interpreter(
           print_writer = new PrintWriter(console_writer, true),
           class_loader = new JARClassLoader)
 
     val thread: Consumer_Thread[Request] = Consumer_Thread.fork("Scala_Console")
     {
       case Start(console) =>
         interp.bind("view", "org.gjt.sp.jedit.View", console.getView)
         interp.bind("console", "console.Console", console)
         interp.interpret("import isabelle._; import isabelle.jedit._")
         true
 
       case Execute(console, out, err, command) =>
         with_console(console, out, err) {
           try {
             running.change(_ => Some(Thread.currentThread()))
             interp.interpret(command)
           }
           finally {
             running.change(_ => None)
             Exn.Interrupt.dispose()
           }
           GUI_Thread.later {
             if (err != null) err.commandDone()
             out.commandDone()
           }
           true
         }
     }
   }
 
 
   /* jEdit console methods */
 
   override def openConsole(console: Console): Unit =
   {
     val interp = new Interpreter
     interp.thread.send(Start(console))
     interpreters += (console -> interp)
   }
 
   override def closeConsole(console: Console): Unit =
   {
     interpreters.get(console) match {
       case Some(interp) =>
         interp.interrupt()
         interp.thread.shutdown()
         interpreters -= console
       case None =>
     }
   }
 
   override def printInfoMessage(out: Output): Unit =
   {
     out.print(null,
      "This shell evaluates Isabelle/Scala expressions.\n\n" +
      "The contents of package isabelle and isabelle.jedit are imported.\n" +
      "The following special toplevel bindings are provided:\n" +
      "  view    -- current jEdit/Swing view (e.g. view.getBuffer, view.getTextArea)\n" +
      "  console -- jEdit Console plugin\n" +
      "  PIDE    -- Isabelle/PIDE plugin (e.g. PIDE.session, PIDE.snapshot, PIDE.rendering)\n")
   }
 
   override def printPrompt(console: Console, out: Output): Unit =
   {
     out.writeAttrs(ConsolePane.colorAttributes(console.getInfoColor), "scala>")
     out.writeAttrs(ConsolePane.colorAttributes(console.getPlainColor), " ")
   }
 
   override def execute(
     console: Console, input: String, out: Output, err: Output, command: String): Unit =
   {
     interpreters(console).thread.send(Execute(console, out, err, command))
   }
 
   override def stop(console: Console): Unit =
     interpreters.get(console).foreach(_.interrupt())
 }