Disable Reconnect
You can disable automatic reconnect with connection options:
// Disable reconnect attempts
nc, err := nats.Connect("demo.nats.io", nats.NoReconnect())
if err != nil {
	log.Fatal(err)
}
defer nc.Close()
// Do something with the connection
Options options = new Options.Builder().
                            server("nats://demo.nats.io:4222").
                            noReconnect(). // Disable reconnect attempts
                            build();
Connection nc = Nats.connect(options);
// Do something with the connection
nc.close();
nc = NATS()
await nc.connect(
   servers=[
      "nats://demo.nats.io:1222",
      "nats://demo.nats.io:1223",
      "nats://demo.nats.io:1224"
      ],
   allow_reconnect=False,
   )
# Do something with the connection
await nc.close()