To connect in your code you use:
Socket socket = new Socket(server_IP,server_Port);
So you could use:
Socket socket = new Socket("192.168.1.4", 5555);
It looks like you have this in your code so I'm not sure what problem you're having.
Don't forget that you have to setup your router to forward ports if it is located outside of your local network.
Don't forget that if you are running a firewall, this can also interfere with the connection.