Index: src/org/openstreetmap/josm/data/osm/DataSet.java
===================================================================
--- src/org/openstreetmap/josm/data/osm/DataSet.java	(revision 272)
+++ src/org/openstreetmap/josm/data/osm/DataSet.java	(revision 273)
@@ -108,5 +108,5 @@
 	public void setSelected(OsmPrimitive... osm) {
 		clearSelection();
-		if (osm.length == 0)
+		if (osm.length == 0 || (osm.length == 1 && osm[0] == null))
 			return;
 		for (OsmPrimitive o : osm)
Index: src/org/openstreetmap/josm/gui/dialogs/PropertiesDialog.java
===================================================================
--- src/org/openstreetmap/josm/gui/dialogs/PropertiesDialog.java	(revision 272)
+++ src/org/openstreetmap/josm/gui/dialogs/PropertiesDialog.java	(revision 273)
@@ -214,5 +214,5 @@
 		// Refresh the values model when focus is gained 
 		editor.addFocusListener(new FocusAdapter() {
-            public void focusGained(FocusEvent e) {
+            @Override public void focusGained(FocusEvent e) {
             	String key = keys.getEditor().getItem().toString();
             	if (allData.containsKey(key)) {
Index: src/org/openstreetmap/josm/tools/AutoCompleteComboBox.java
===================================================================
--- src/org/openstreetmap/josm/tools/AutoCompleteComboBox.java	(revision 272)
+++ src/org/openstreetmap/josm/tools/AutoCompleteComboBox.java	(revision 273)
@@ -29,5 +29,5 @@
 		}
 
-		public void remove(int offs, int len) throws BadLocationException {
+		@Override public void remove(int offs, int len) throws BadLocationException {
 			if (selecting)
 				return;
@@ -35,5 +35,5 @@
 		}
 
-		public void insertString(int offs, String str, AttributeSet a) throws BadLocationException {
+		@Override public void insertString(int offs, String str, AttributeSet a) throws BadLocationException {
 			super.insertString(offs, str, a);