public boolean isOnlyShared() {
        return isShared() && groups.isEmpty();
    }
Returns true if this item belongs ONLY to shared groups. This means that the item is
considered to be "only shared" if it doesn't belong to a personal group but only to shared
groups.

@return true if this item belongs ONLY to shared groups.
xmppserver/src/main/java/org/jivesoftware/openfire/roster/RosterItem.java