public void run() { for (SenderEntry val : send_table.values()) { Table<Message> buf = val != null ? val.sent_msgs : null; if (buf != null && !buf.isEmpty()) { long from = buf.getHighestDelivered() + 1, to = buf.getHighestReceived(); List<Message> list = buf.get(from, to); if (list != null) { for (Message msg : list) retransmit(msg); } } } }