Prevent program from running multiple times

boolean isexist;
        final String PID = "Start";
        try {
            JUnique.acquireLock(PID);
            isexist = false;
        } catch (AlreadyLockedException e1) {
            isexist = true;
        }
        if (isexist) {
            Log.OutLog("%s已开启，无需再次启动。", PID);
            System.exit(0);
        }

it.sauronsoftware.junique.JUnique