Index: trunk/src/org/openstreetmap/josm/data/osm/DataSet.java
===================================================================
--- trunk/src/org/openstreetmap/josm/data/osm/DataSet.java	(revision 6284)
+++ trunk/src/org/openstreetmap/josm/data/osm/DataSet.java	(revision 6285)
@@ -88,5 +88,5 @@
  * @author imi
  */
-public class DataSet implements Cloneable, ProjectionChangeListener {
+public final class DataSet implements Cloneable, ProjectionChangeListener {
 
     /**
Index: trunk/src/org/openstreetmap/josm/gui/mappaint/Cascade.java
===================================================================
--- trunk/src/org/openstreetmap/josm/gui/mappaint/Cascade.java	(revision 6284)
+++ trunk/src/org/openstreetmap/josm/gui/mappaint/Cascade.java	(revision 6285)
@@ -18,5 +18,5 @@
  * Simple map of properties with dynamic typing.
  */
-public class Cascade implements Cloneable {
+public final class Cascade implements Cloneable {
 
     public static final Cascade EMPTY_CASCADE = new Cascade();