Added missing serialVersionUIDs

src/main/java/org/rometools/certiorem/example/HubServlet.java

@@ -18,8 +18,11 @@ import com.google.inject.Singleton;
 @Singleton
 public class HubServlet extends AbstractHubServlet {
 
+    private static final long serialVersionUID = 1L;
+
     @Inject
     public HubServlet(final Hub hub) {
         super(hub);
     }
+
 }

src/main/java/org/rometools/certiorem/example/NotifyTest.java

@@ -25,6 +25,8 @@ import com.google.inject.Singleton;
 @Singleton
 public class NotifyTest extends HttpServlet {
 
+    private static final long serialVersionUID = 1L;
+
     @Override
     public void doGet(final HttpServletRequest request, final HttpServletResponse response) throws ServletException {
         final Publisher pub = new Publisher();
@@ -35,4 +37,5 @@ public class NotifyTest extends HttpServlet {
             throw new ServletException(ex);
         }
     }
+
 }

src/main/java/org/rometools/certiorem/example/SubServlet.java

@@ -18,6 +18,8 @@ import com.google.inject.Singleton;
 @Singleton
 public class SubServlet extends AbstractSubServlet {
 
+    private static final long serialVersionUID = 1L;
+
     @Inject
     public SubServlet(final Subscriptions subscriptions) {
         super(subscriptions);

src/main/java/org/rometools/certiorem/example/SubTest.java

@@ -24,6 +24,8 @@ import com.google.inject.Singleton;
 @Singleton
 public class SubTest extends HttpServlet {
 
+    private static final long serialVersionUID = 1L;
+
     private final Subscriptions subs;
 
     @Inject