diff --git a/src/main/java/caosdb/server/CaosAuthenticator.java b/src/main/java/caosdb/server/CaosAuthenticator.java
index efe02c151eb3ce77e973ea5e8d95a779dd912a57..0cc6cc3ddfedf6e45a708d3eeed2ed99b1b076d2 100644
--- a/src/main/java/caosdb/server/CaosAuthenticator.java
+++ b/src/main/java/caosdb/server/CaosAuthenticator.java
@@ -66,7 +66,7 @@ public class CaosAuthenticator extends Authenticator {
     // anonymous users
     if (!subject.isAuthenticated()
         && CaosDBServer.getServerProperty(ServerProperties.KEY_AUTH_OPTIONAL)
-        .equalsIgnoreCase("TRUE")) {
+            .equalsIgnoreCase("TRUE")) {
       subject.login(AuthenticationUtils.ANONYMOUS_USER);
     }
     return subject.isAuthenticated();
diff --git a/src/main/java/caosdb/server/CaosDBServer.java b/src/main/java/caosdb/server/CaosDBServer.java
index c5ab6286d1160638075d40857027e66eb285b431..2aa6ad3a5b6d89aa74bc10d2654327f5919aca45 100644
--- a/src/main/java/caosdb/server/CaosDBServer.java
+++ b/src/main/java/caosdb/server/CaosDBServer.java
@@ -277,7 +277,9 @@ public class CaosDBServer extends Application {
 
     // Create an application (this class).
     final Application application = new CaosDBServer();
-    application.getStatusService().setContactEmail(getServerProperty(ServerProperties.KEY_ADMIN_EMAIL));
+    application
+        .getStatusService()
+        .setContactEmail(getServerProperty(ServerProperties.KEY_ADMIN_EMAIL));
     application
         .getStatusService()
         .setHomeRef(new Reference(getServerProperty(ServerProperties.KEY_CONTEXT_ROOT) + "/"));
diff --git a/src/main/java/caosdb/server/resource/AbstractCaosDBServerResource.java b/src/main/java/caosdb/server/resource/AbstractCaosDBServerResource.java
index e8bc5f4932f4c3972b6e64bd5d234e8c7898794b..709825c8176e0e759249efb41c5e8fd075829959 100644
--- a/src/main/java/caosdb/server/resource/AbstractCaosDBServerResource.java
+++ b/src/main/java/caosdb/server/resource/AbstractCaosDBServerResource.java
@@ -38,6 +38,7 @@ import java.io.UnsupportedEncodingException;
 import java.security.NoSuchAlgorithmException;
 import java.sql.SQLException;
 import java.util.ArrayList;
+import java.util.Collection;
 import java.util.HashMap;
 import java.util.LinkedList;
 import java.util.NoSuchElementException;
@@ -199,13 +200,15 @@ public abstract class AbstractCaosDBServerResource extends ServerResource {
    * @param user
    */
   private void addRoles(Element userInfo, Subject user) {
-    Element roles = new Element("Roles");
-    for (String role : UserSources.resolve(user.getPrincipals())) {
+    Collection<String> roles = UserSources.resolve(user.getPrincipals());
+    if (roles == null) return;
+    Element rs = new Element("Roles");
+    for (String role : roles) {
       Element r = new Element("Role");
       r.addContent(role);
-      roles.addContent(r);
+      rs.addContent(r);
     }
-    userInfo.addContent(roles);
+    userInfo.addContent(rs);
   }
 
   /**