Connect locally via IP Address

Question

I am setting up a MAMP Pro development environment and I would like to use the feature that lets me share a website that I am working on over the internet. I would provide people with my IP Address and they would be able to see what I am working on.
The problem I am having is letting other computers see my iMac. I have a MacBook Air that I use as well but I can see that from the iMac just fine. I can type the IP address for the MacBook Air into the address bar of Chrome and I'll get a page that simply says, "It Works". I can also type 'mymacbokairexxx.local' into the address bar and establish a connection.
When type the local ip address of the iMac into the MacBook Air I get nothing; a can't connect page from Chrome. Same for the the joshs-imacxxx.local' routine.
I can use AIr Drop and Back to my Mac for both computers in both directions. I have checked the Time Capslue and nothing obvious pops out. I have made my iMac's sharing settings look like my MacBook Air's since those seem to work. Still nothing.

Answer 1

below is sample code for rmi client.
if you know the ip address of rmi registry, use that in place of ip_address_of _rmiregisty
if you only know a dns name of rmiregistry, you should use dns server or ask system administrator the ip address of rmiregistry.
if there's firewall between client and server, ask your system administrator.
if there's nat between client and server, I don't know exactly.
good luch ^^
import java.rmi.*;
public class HelloRMIClient {
    public static void main(String[] args)    throws Exception {
        if (System.getSecurityManager() == null) {
            System.setSecurityManager(new RMISecurityManager());
        IHello h =
                (IHello)Naming.lookup(
                          "rmi://ip_address_of _rmiregisty/object_identifier/b] "
String str = h.sayHello("John");
System.out.println(str);
} // main
} // HelloRMIClient class