From a552d88c5481accaf135c5315a994cad0944fbf7 Mon Sep 17 00:00:00 2001
From: Michael Jumper <mjumper@apache.org>
Date: Thu, 27 Sep 2018 20:06:18 -0700
Subject: [PATCH] GUACAMOLE-220: Clarify group rename validation logic.

---
 .../auth/jdbc/usergroup/UserGroupService.java      | 14 +++++---------
 1 file changed, 5 insertions(+), 9 deletions(-)

diff --git a/extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-base/src/main/java/org/apache/guacamole/auth/jdbc/usergroup/UserGroupService.java b/extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-base/src/main/java/org/apache/guacamole/auth/jdbc/usergroup/UserGroupService.java
index dfe1ef560..0f4a21683 100644
--- a/extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-base/src/main/java/org/apache/guacamole/auth/jdbc/usergroup/UserGroupService.java
+++ b/extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-base/src/main/java/org/apache/guacamole/auth/jdbc/usergroup/UserGroupService.java
@@ -162,19 +162,15 @@ public class UserGroupService extends ModeledDirectoryObjectService<ModeledUserG
 
         super.beforeUpdate(user, object, model);
         
-        // Username must not be blank
+        // Group names must not be blank
         if (model.getIdentifier() == null || model.getIdentifier().trim().isEmpty())
             throw new GuacamoleClientException("The group name must not be blank.");
         
-        // Check whether such a group is already present
+        // Do not allow groups to be renamed if the name collides with that of
+        // another, existing group
         UserGroupModel existing = userGroupMapper.selectOne(model.getIdentifier());
-        if (existing != null) {
-
-            // Do not rename to existing user group
-            if (!existing.getObjectID().equals(model.getObjectID()))
-                throw new GuacamoleClientException("Group \"" + model.getIdentifier() + "\" already exists.");
-            
-        }
+        if (existing != null && !existing.getObjectID().equals(model.getObjectID()))
+            throw new GuacamoleClientException("Group \"" + model.getIdentifier() + "\" already exists.");
 
     }