src/Pure/GUI/color_value.scala

 
 package isabelle
 
 
 import java.awt.Color
+import java.util.Locale
 
 
 object Color_Value
 {
   private var cache = Map.empty[String, Color]

   {
     val r = new java.lang.Integer(c.getRed)
     val g = new java.lang.Integer(c.getGreen)
     val b = new java.lang.Integer(c.getBlue)
     val a = new java.lang.Integer(c.getAlpha)
-    Word.uppercase(String.format("%02x%02x%02x%02x", r, g, b, a))
+    Word.uppercase(String.format(Locale.ROOT, "%02x%02x%02x%02x", r, g, b, a))
   }
 
   def apply(s: String): Color =
     synchronized {
       cache.get(s) match {