Index: trunk/src/org/openstreetmap/josm/tools/ImageResizeMode.java
===================================================================
--- trunk/src/org/openstreetmap/josm/tools/ImageResizeMode.java	(revision 17073)
+++ trunk/src/org/openstreetmap/josm/tools/ImageResizeMode.java	(revision 17074)
@@ -90,4 +90,5 @@
      * @param sourceIcon the source icon to draw
      * @return a new buffered image
+     * @throws IllegalArgumentException if renderer or sourceIcon is null
      */
     BufferedImage createBufferedImage(Dimension dim, Dimension icon, Consumer<Graphics2D> renderer, Image sourceIcon) {
@@ -103,5 +104,5 @@
             g.drawImage(sourceIcon, 0, 0, null);
         } else {
-            throw new NullPointerException("renderer or sourceIcon");
+            throw new IllegalArgumentException("renderer or sourceIcon");
         }
         return bufferedImage;