套接字创建超时

Question

I'm working on an assignment for my Distributed Computing course, which deals with basic sockets and I'm having a bit of a problem. My code executes and runs properly via SSH on university computers but from my laptop it doesn't.

I have a server java file that is running on a university computer via SSH. If I start another SSH session and run my code from that computer everything runs smoothly. However, if I execute that code off of my local machine I get a Socket Timed Out error.

Here's the code for the Client file, which throws the error:

try {
    addr = InetAddress.getByName("___IP_Here____");
    sock = new Socket(addr,3165);
} catch (Exception e) {
    System.err.println("Creating Socket failed.");
    System.out.println(e);
    System.exit(1);
}

Here's the Server code for creating the server:

try {
    addr = InetAddress.getLocalHost();
    sock = new ServerSocket(3165,3,addr);
} catch (Exception e) {
    System.err.println("Creating ServerSocket failed.");
    System.out.println(e);
    System.exit(1);
}

I thought that it might be a problem with the Firewall and I added exceptions to allow Java in both inbound and outbound. Does anyone have an idea of what could possibly be wrong?

EDIT: The server socket has a timeout of 0, which is infinity. http://download.java.net/jdk7/archive/b123/docs/api/java/net/ServerSocket.html#getSoTimeout()

EDIT: This is actually a university security issue.

Answer 1

Firewall might be your problem. Allowing java might be not enough, check for ports and rules with higher priority. If you are in a safe environment, or disconnected you might try to turn it off to confirm if it is the firewall or not. BTW, close your resources or consider using try-with-resources instead of simple try and catch, this other thing to look for, try to kill your process and check if you can connect.