In NB 7.4 a new "Test Connection" was introduced in Options Panel.

When I press this button I get "connect: Address is invalid on local machine, or port is not valid on remote machine".

Rather strange as I do not have a proxy between my workstation and the Internet. In fact I don't mess with these settings in NB at all since there's no need. I think the problem here is that the NB developer has been too focused on the case about testing with a Proxy that the simple case - when there's no proxy - has been kind of forgotten. The button says "Test connection" which leads me to believe that it is a GENERAL test of Internet connectivity, not one specifically for the case when there's a proxy involved.

Digging further into the NB Platform source code and log file it seems the problem arises when NB tries to figure out which port to use for the test against http://netbeans.org (which is the address that NB uses for the test).

NB will try to retrieve the port for the test via Preferences. As there are no Preferences the port will default to "" (empty string) which cannot be translated to integer which results in a NumberFormatException and is probably the true cause of the somewhat misleading UI error message when then "Test Connection" button is pressed.

I believe the logic for figuring out the host (via Preferences) is similarly flawed.

All in all I believe the problem can be fixed in org.netbeans.coreProxySettings.java, currently:

    public static String getTestSystemHttpHost() {
        return getPreferences().get(TEST_SYSTEM_PROXY_HTTP_HOST, "");
    }
    
    public static String getTestSystemHttpPort() {
        return getPreferences().get(TEST_SYSTEM_PROXY_HTTP_PORT, "");
    }


could/should be replaced with:


    public static String getTestSystemHttpHost() {
        return getPreferences().get(TEST_SYSTEM_PROXY_HTTP_HOST, HTTP_CONNECTION_TEST_URL);
    }
    
    public static String getTestSystemHttpPort() {
        return getPreferences().get(TEST_SYSTEM_PROXY_HTTP_PORT, "80");
    }


although I cannot say for sure.

Actually I first discovered the problem on an RCP application but the problem of course applies equally to the IDE.