@Override
    public boolean hasServerRoute(DomainPair pair) {
        return serversCache.containsKey(pair);
    }
Gets the non-negative session from a minimal priority.

@param sessions The sessions.
@param min      The minimal priority.
@return The filtered sessions.
xmppserver/src/main/java/org/jivesoftware/openfire/spi/RoutingTableImpl.java