Index: trunk/src/org/openstreetmap/josm/data/vector/VectorWay.java
===================================================================
--- trunk/src/org/openstreetmap/josm/data/vector/VectorWay.java	(revision 18213)
+++ trunk/src/org/openstreetmap/josm/data/vector/VectorWay.java	(revision 18214)
@@ -74,6 +74,8 @@
         this.nodes.forEach(node -> node.removeReferrer(this));
         this.nodes.clear();
-        nodes.forEach(node -> node.addReferrer(this));
-        this.nodes.addAll(nodes);
+        if (nodes != null) {
+            nodes.forEach(node -> node.addReferrer(this));
+            this.nodes.addAll(nodes);
+        }
         this.cachedBBox = null;
     }