for #40: Allow UserGroup services to work for non-local users

JIDs on domains other than the local domain can be in groups. This commit adds support for that in the UserGroups endpoints, with the exception of an endpoint that would make the code iterate over all groups in the system.

src/java/org/jivesoftware/openfire/plugin/rest/controller/UserServiceController.java

@@ -401,6 +401,9 @@ public void deleteRosterItem(String username, String rosterJid) throws SharedGro
      */
     public List<String> getUserGroups(String username) throws ServiceException {
         log("Get user groups for user: " + username);
+        if (username.contains("@")) {
+            throw new ServiceException("This service cannot be used for non-local users.", username, ExceptionType.GROUP_NOT_FOUND, Response.Status.INTERNAL_SERVER_ERROR);
+        }
         User user = getAndCheckUser(username);
         Collection<Group> groups = GroupManager.getInstance().getGroups(user);
         List<String> groupNames = new ArrayList<String>();
@@ -438,7 +441,7 @@ public void addUserToGroups(String username, UserGroupsEntity userGroupsEntity)
                 groups.add(group);
             }
             for (Group group : groups) {
-                group.getMembers().add(server.createJID(username, null));
+                group.getMembers().add(username.contains("@") ? new JID(username) : XMPPServer.getInstance().createJID(username, null));
             }
         }
     }
@@ -461,7 +464,7 @@ public void addUserToGroup(String username, String groupName) throws ServiceExce
             group = GroupController.getInstance().createGroup(new GroupEntity(groupName, ""));
         }
 
-        group.getMembers().add(server.createJID(username, null));
+        group.getMembers().add(username.contains("@") ? new JID(username) : XMPPServer.getInstance().createJID(username, null));
     }
 
     /**
@@ -487,7 +490,7 @@ public void deleteUserFromGroups(String username, UserGroupsEntity userGroupsEnt
                             Response.Status.NOT_FOUND, e);
                 }
                 log("Removing user: " + username + " from the group: " + groupName);
-                group.getMembers().remove(server.createJID(username, null));
+                group.getMembers().remove(username.contains("@") ? new JID(username) : XMPPServer.getInstance().createJID(username, null));
             }
         }
     }
@@ -508,7 +511,7 @@ public void deleteUserFromGroup(String username, String groupName) throws Servic
             throw new ServiceException("Could not find group", groupName, ExceptionType.GROUP_NOT_FOUND,
                     Response.Status.NOT_FOUND, e);
         }
-        group.getMembers().remove(server.createJID(username, null));
+        group.getMembers().remove(username.contains("@") ? new JID(username) : XMPPServer.getInstance().createJID(username, null));
     }
 
     /**