Index: trunk/src/org/openstreetmap/josm/gui/mappaint/DividedScale.java
===================================================================
--- trunk/src/org/openstreetmap/josm/gui/mappaint/DividedScale.java	(revision 10235)
+++ trunk/src/org/openstreetmap/josm/gui/mappaint/DividedScale.java	(revision 10236)
@@ -23,10 +23,12 @@
 public class DividedScale<T> {
 
-    // this exception type is for debugging #8997 and can later be replaced
-    // by AssertionError
-    public static class RangeViolatedError extends Error {
-        public RangeViolatedError() {
-        }
-
+    /**
+     * This exception type is for debugging #8997 and can later be replaced by AssertionError
+     */
+    public static class RangeViolatedError extends RuntimeException {
+        /**
+         * Constructs a new {@code RangeViolatedError}
+         * @param message error message
+         */
         public RangeViolatedError(String message) {
             super(message);