Question

My new laptop (Alienware m17x) throws a java.net.SocketException: Invalid argument: connect when I run the following basic code:

Server.java:

public static void main (String[] args) throws Exception {
        
    ServerSocket serverSocket = new ServerSocket (8888);
    Socket socket = serverSocket.accept();
}

Client.java:

public static void main (String[] args) throws Exception {
    Socket socket = new Socket ("localhost", 8888);
}

Every time I run Client.java (after starting Server.java) I get this socket exception. Here’s the full trace of the exception:

Exception in thread "main" java.net.SocketException: Invalid argument: connect
    at java.net.DualStackPlainSocketImpl.connect0(Native Method)
    at java.net.DualStackPlainSocketImpl.socketConnect(Unknown Source)
    at java.net.AbstractPlainSocketImpl.doConnect(Unknown Source)
    at java.net.AbstractPlainSocketImpl.connectToAddress(Unknown Source)
    at java.net.AbstractPlainSocketImpl.connect(Unknown Source)
    at java.net.PlainSocketImpl.connect(Unknown Source)
    at java.net.SocksSocketImpl.connect(Unknown Source)
    at java.net.Socket.connect(Unknown Source)
    at java.net.Socket.connect(Unknown Source)
    at java.net.Socket.<init>(Unknown Source)
    at java.net.Socket.<init>(Unknown Source)
    at Client.main(Client.java:5)

I’ve tried a few things, but no luck the exception is always thrown. Here’s what I have concluded:

• Changing the port numbers changes nothing.
• It’s not a problem with the network. I have gotten the exception at school and at home.
• I’ve reinstalled the JVM and the JDK but no luck.
• This only occurs on one machine. I have run the same code on my desktop and I have not gotten any exceptions. I am using Windows 7 on both.
• It is not blocked by a firewall. I have turned my firewalls off and I still have this issue.

What should I do or check for to resolve this issue?

EDIT:
route print outputs:

===========================================================================
Interface List
 15...e4 d5 3d 08 cb 83 ......Killer Wireless-N 1103 Network Adapter
 13...d0 df 9a b5 73 dc ......Bluetooth Device (Personal Area Network)
 11...d4 be d9 00 10 65 ......Atheros AR8151 PCI-E Gigabit Ethernet Controller (NDIS 6.20)
  1...........................Software Loopback Interface 1
 17...00 00 00 00 00 00 00 e0 Teredo Tunneling Pseudo-Interface
 16...00 00 00 00 00 00 00 e0 Microsoft ISATAP Adapter #2
 18...00 00 00 00 00 00 00 e0 Microsoft ISATAP Adapter
 19...00 00 00 00 00 00 00 e0 Microsoft ISATAP Adapter #3
===========================================================================

IPv4 Route Table
===========================================================================
Active Routes:
Network Destination        Netmask          Gateway       Interface  Metric
          0.0.0.0          0.0.0.0      192.168.0.1    192.168.0.191     25
        127.0.0.0        255.0.0.0         On-link         127.0.0.1    306
        127.0.0.1  255.255.255.255         On-link         127.0.0.1    306
  127.255.255.255  255.255.255.255         On-link         127.0.0.1    306
      192.168.0.0    255.255.255.0         On-link     192.168.0.191    281
    192.168.0.191  255.255.255.255         On-link     192.168.0.191    281
    192.168.0.255  255.255.255.255         On-link     192.168.0.191    281
        224.0.0.0        240.0.0.0         On-link         127.0.0.1    306
        224.0.0.0        240.0.0.0         On-link     192.168.0.191    281
  255.255.255.255  255.255.255.255         On-link         127.0.0.1    306
  255.255.255.255  255.255.255.255         On-link     192.168.0.191    281
===========================================================================
Persistent Routes:
  None

IPv6 Route Table
===========================================================================
Active Routes:
 If Metric Network Destination      Gateway
 17     58 ::/0                     On-link
  1    306 ::1/128                  On-link
 17     58 2001::/32                On-link
 17    306 2001:0:4137:9e76:28f3:2721:524f:e2ef/128
                                    On-link
 15    281 fe80::/64                On-link
 17    306 fe80::/64                On-link
 17    306 fe80::28f3:2721:524f:e2ef/128
                                    On-link
 15    281 fe80::68c1:bc79:fefa:88a2/128
                                    On-link
  1    306 ff00::/8                 On-link
 17    306 ff00::/8                 On-link
 15    281 ff00::/8                 On-link
===========================================================================
Persistent Routes:
  None

EDIT: As @PhilippeLM and @beny23 made me realize, setting the java system variable java.net.preferIPv4Stack to true solves my problem. However I want a permanent fix. I don’t want to specify the system variable every time I run a java application.

Here’s what I’ve tried with no luck once again:

• Setting my machine preferences to prefer IPv4 by following these steps
• Adding the line java.net.preferIPv4Stack=true to the net.properties file in %JAVA_HOME%\jre\lib.

Is there anything else I can try?

Answer 1

I have an Alienware m17x R3 and I found that I had the exact same error with Java, though I encountered it with Minecraft. Installing older Java6u33 fixed the issue but I found that newer updates of Java7 still weren’t working even after waiting several months. So I eventually went to the Dell website and downloaded the most recent network drivers for my Alienware laptop (since Alienware is now owned by Dell) and that fixed the problem right away.