Index: trunk/src/org/openstreetmap/josm/gui/preferences/PreferenceSetting.java
===================================================================
--- trunk/src/org/openstreetmap/josm/gui/preferences/PreferenceSetting.java	(revision 4987)
+++ trunk/src/org/openstreetmap/josm/gui/preferences/PreferenceSetting.java	(revision 4989)
@@ -2,4 +2,8 @@
 package org.openstreetmap.josm.gui.preferences;
 
+/**
+ * Base interface of Preferences settings, should not be directly implemented, 
+ * see {@link TabPreferenceSetting} and {@link SubPreferenceSetting}.
+ */
 public interface PreferenceSetting {
     /**
Index: trunk/src/org/openstreetmap/josm/gui/preferences/TabPreferenceSetting.java
===================================================================
--- trunk/src/org/openstreetmap/josm/gui/preferences/TabPreferenceSetting.java	(revision 4987)
+++ trunk/src/org/openstreetmap/josm/gui/preferences/TabPreferenceSetting.java	(revision 4989)
@@ -2,4 +2,9 @@
 package org.openstreetmap.josm.gui.preferences;
 
+/**
+ * Preference settings, that display a top level tab.
+ *
+ * This preference setting's addGui method is called after the user clicked the tab.
+ */
 public interface TabPreferenceSetting extends PreferenceSetting {