Index: /trunk/src/org/openstreetmap/josm/actions/downloadtasks/DownloadReferrersTask.java
===================================================================
--- /trunk/src/org/openstreetmap/josm/actions/downloadtasks/DownloadReferrersTask.java	(revision 10305)
+++ /trunk/src/org/openstreetmap/josm/actions/downloadtasks/DownloadReferrersTask.java	(revision 10306)
@@ -45,9 +45,9 @@
     private OsmServerReader reader;
     /** the target layer */
-    private OsmDataLayer targetLayer;
+    private final OsmDataLayer targetLayer;
     /** the collection of child primitives */
-    private Map<Long, OsmPrimitiveType> children;
+    private final Map<Long, OsmPrimitiveType> children;
     /** the parents */
-    private DataSet parents;
+    private final DataSet parents;
 
     /**
Index: /trunk/src/org/openstreetmap/josm/data/preferences/PreferencesReader.java
===================================================================
--- /trunk/src/org/openstreetmap/josm/data/preferences/PreferencesReader.java	(revision 10305)
+++ /trunk/src/org/openstreetmap/josm/data/preferences/PreferencesReader.java	(revision 10306)
@@ -42,6 +42,6 @@
     private XMLStreamReader parser;
     private int version;
-    private Reader reader;
-    private File file;
+    private final Reader reader;
+    private final File file;
 
     private final boolean defaults;
Index: /trunk/src/org/openstreetmap/josm/gui/dialogs/RelationListDialog.java
===================================================================
--- /trunk/src/org/openstreetmap/josm/gui/dialogs/RelationListDialog.java	(revision 10305)
+++ /trunk/src/org/openstreetmap/josm/gui/dialogs/RelationListDialog.java	(revision 10306)
@@ -124,5 +124,5 @@
     private final transient HighlightHelper highlightHelper = new HighlightHelper();
     private final boolean highlightEnabled = Main.pref.getBoolean("draw.target-highlight", true);
-    private transient RecentRelationsAction recentRelationsAction;
+    private final transient RecentRelationsAction recentRelationsAction;
 
     /**
Index: /trunk/src/org/openstreetmap/josm/gui/dialogs/layer/LayerVisibilityAction.java
===================================================================
--- /trunk/src/org/openstreetmap/josm/gui/dialogs/layer/LayerVisibilityAction.java	(revision 10305)
+++ /trunk/src/org/openstreetmap/josm/gui/dialogs/layer/LayerVisibilityAction.java	(revision 10306)
@@ -45,5 +45,5 @@
     private final JPopupMenu popup;
     private SideButton sideButton;
-    private JCheckBox visibilityCheckbox;
+    private final JCheckBox visibilityCheckbox;
     final OpacitySlider opacitySlider = new OpacitySlider();
     private final ArrayList<FilterSlider<?>> sliders = new ArrayList<>();
Index: /trunk/src/org/openstreetmap/josm/gui/dialogs/properties/TagEditHelper.java
===================================================================
--- /trunk/src/org/openstreetmap/josm/gui/dialogs/properties/TagEditHelper.java	(revision 10305)
+++ /trunk/src/org/openstreetmap/josm/gui/dialogs/properties/TagEditHelper.java	(revision 10306)
@@ -656,5 +656,5 @@
         private final List<JosmAction> recentTagsActions = new ArrayList<>();
         protected final transient FocusAdapter focus;
-        private JPanel mainPanel;
+        private final JPanel mainPanel;
         private JPanel recentTagsPanel;
 
Index: /trunk/src/org/openstreetmap/josm/gui/dialogs/relation/RelationTreeModel.java
===================================================================
--- /trunk/src/org/openstreetmap/josm/gui/dialogs/relation/RelationTreeModel.java	(revision 10305)
+++ /trunk/src/org/openstreetmap/josm/gui/dialogs/relation/RelationTreeModel.java	(revision 10306)
@@ -20,5 +20,5 @@
  * {@link #populate(Relation)} and {@link #populate(List)} respectively.
  *
- *
+ * @since 1828
  */
 public class RelationTreeModel implements TreeModel {
@@ -27,5 +27,5 @@
 
     /** the tree model listeners */
-    private CopyOnWriteArrayList<TreeModelListener> listeners;
+    private final CopyOnWriteArrayList<TreeModelListener> listeners;
 
     /**
@@ -34,26 +34,4 @@
     public RelationTreeModel() {
         this.root = null;
-        listeners = new CopyOnWriteArrayList<>();
-    }
-
-    /**
-     * constructor
-     * @param root the root relation
-     */
-    public RelationTreeModel(Relation root) {
-        this.root = root;
-        listeners = new CopyOnWriteArrayList<>();
-    }
-
-    /**
-     * constructor
-     *
-     * @param members a list of members
-     */
-    public RelationTreeModel(List<RelationMember> members) {
-        if (members == null) return;
-        Relation root = new Relation();
-        root.setMembers(members);
-        this.root = root;
         listeners = new CopyOnWriteArrayList<>();
     }
Index: /trunk/src/org/openstreetmap/josm/gui/layer/NativeScaleLayer.java
===================================================================
--- /trunk/src/org/openstreetmap/josm/gui/layer/NativeScaleLayer.java	(revision 10305)
+++ /trunk/src/org/openstreetmap/josm/gui/layer/NativeScaleLayer.java	(revision 10306)
@@ -27,12 +27,12 @@
          * Scale factor, same unit as in {@link NavigatableComponent}
          */
-        private double scale;
+        private final double scale;
 
         /**
          * True if this scale is native resolution for data source.
          */
-        private boolean isNative;
-
-        private int index;
+        private final boolean isNative;
+
+        private final int index;
 
         /**
@@ -78,15 +78,8 @@
 
     /**
-     * List of scales, may include intermediate steps
-     * between native resolutions
+     * List of scales, may include intermediate steps between native resolutions
      */
     class ScaleList  {
-        private List<Scale> scales = new ArrayList<>();
-
-        protected ScaleList(double[] scales) {
-            for (int i = 0; i < scales.length; i++) {
-                this.scales.add(new Scale(scales[i], i));
-            }
-        }
+        private final List<Scale> scales = new ArrayList<>();
 
         protected ScaleList() {
Index: /trunk/src/org/openstreetmap/josm/gui/preferences/projection/ProjectionPreference.java
===================================================================
--- /trunk/src/org/openstreetmap/josm/gui/preferences/projection/ProjectionPreference.java	(revision 10305)
+++ /trunk/src/org/openstreetmap/josm/gui/preferences/projection/ProjectionPreference.java	(revision 10306)
@@ -300,6 +300,6 @@
     private final JPanel projSubPrefPanelWrapper = new JPanel(new GridBagLayout());
 
-    private JLabel projectionCodeLabel = new JLabel(tr("Projection code"));
-    private Component projectionCodeGlue = GBC.glue(5, 0);
+    private final JLabel projectionCodeLabel = new JLabel(tr("Projection code"));
+    private final Component projectionCodeGlue = GBC.glue(5, 0);
     private final JLabel projectionCode = new JLabel();
     private final JLabel projectionNameLabel = new JLabel(tr("Projection name"));
Index: /trunk/src/org/openstreetmap/josm/gui/preferences/server/OverpassServerPreference.java
===================================================================
--- /trunk/src/org/openstreetmap/josm/gui/preferences/server/OverpassServerPreference.java	(revision 10305)
+++ /trunk/src/org/openstreetmap/josm/gui/preferences/server/OverpassServerPreference.java	(revision 10306)
@@ -37,5 +37,5 @@
     private static final BooleanProperty FOR_MULTI_FETCH = new BooleanProperty("download.overpass.for-multi-fetch", false);
 
-    private HistoryComboBox overpassServer = new HistoryComboBox();
+    private final HistoryComboBox overpassServer = new HistoryComboBox();
     private final JCheckBox forMultiFetch = new JCheckBox(tr("Use Overpass server for object downloads"));
 
Index: /trunk/src/org/openstreetmap/josm/tools/bugreport/DebugTextDisplay.java
===================================================================
--- /trunk/src/org/openstreetmap/josm/tools/bugreport/DebugTextDisplay.java	(revision 10305)
+++ /trunk/src/org/openstreetmap/josm/tools/bugreport/DebugTextDisplay.java	(revision 10306)
@@ -15,5 +15,5 @@
  */
 public class DebugTextDisplay extends JScrollPane {
-    private String text;
+    private final String text;
 
     /**
Index: /trunk/src/org/openstreetmap/josm/tools/bugreport/ReportedException.java
===================================================================
--- /trunk/src/org/openstreetmap/josm/tools/bugreport/ReportedException.java	(revision 10305)
+++ /trunk/src/org/openstreetmap/josm/tools/bugreport/ReportedException.java	(revision 10306)
@@ -251,6 +251,6 @@
     private static class Section {
 
-        private String sectionName;
-        private ArrayList<SectionEntry> entries = new ArrayList<>();
+        private final String sectionName;
+        private final ArrayList<SectionEntry> entries = new ArrayList<>();
 
         Section(String sectionName) {
Index: /trunk/test/unit/org/openstreetmap/josm/gui/layer/NativeScaleLayerTest.java
===================================================================
--- /trunk/test/unit/org/openstreetmap/josm/gui/layer/NativeScaleLayerTest.java	(revision 10305)
+++ /trunk/test/unit/org/openstreetmap/josm/gui/layer/NativeScaleLayerTest.java	(revision 10306)
@@ -29,5 +29,4 @@
     public void testTicket12255() {
         assertNull(new NativeScaleLayer.ScaleList(Collections.<Double>emptyList()).getSnapScale(10, 2, false));
-        assertNull(new NativeScaleLayer.ScaleList(new double[0]).getSnapScale(10, 2, false));
     }
 }
