Socket throws an exception, although the port is free

Asked Aug 01 '19 at 19:56

Active Aug 01 '19 at 19:56

Viewed 86 times

I have the method, that should return true, if the socket port is free.

The implementation of the method:

  private def isPortFree(host: String, port: Int): Boolean = {
    import java.net.Socket
    try {
      // Socket try to open a REMOTE port
      new Socket(host, port).close()
      true
    } catch {
      case _: Exception => false
    }
  }

When the object gets initialized, then it throws an exception:

Connection refused (Connection refused)

although the port is available. The host is "0.0.0.0".

I am trying to validate, if the given port is free or not.

asked Aug 01 '19 at 19:56

softshipper

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Did you mean `ServerSocket`? – chrylis -cautiouslyoptimistic- Aug 01 '19 at 20:09
Possible duplicate of [Sockets: Discover port availability using Java](https://stackoverflow.com/questions/434718/sockets-discover-port-availability-using-java) – Mikhail Ionkin Aug 01 '19 at 20:26
I think you should first open socket, like in try-with-resiurces. See link upper – Mikhail Ionkin Aug 01 '19 at 20:29
Why not show the code that is throwing the "Connection Refused" exception? It's hard to imagine what you're doing because you just opened and immediately closed the connection, so there is no connection anymore to be "refused". – President James K. Polk Aug 02 '19 at 03:12
If you create a socket, you are connecting to something. As you mention that the port is free, then there is nothing to connect to. Hence the 'connection refused' error. – Mark Rotteveel Aug 02 '19 at 17:58

Socket throws an exception, although the port is free

0 Answers0