Response failing over HTTPS in Java

问题:

We run crawlers on websites to keep our info up to date. Some websites like this one allow standard navigation with the browser, but they don't send responses when using standard Java libraries. Here's the code I'm using to access the home (index) page,

    try
    {
        URL my_url = new URL("https://www.capitallightingfixture.com");

        URLConnection u = my_url.openConnection();

        if ( u instanceof HttpURLConnection )
        {
            HttpURLConnection http_u = (HttpURLConnection)u;

            System.out.println(http_u.getResponseCode());
        }
    }
    catch (Exception e)
    {
        e.printStackTrace();
    }

When run, this program will throw the following error

javax.net.ssl.SSLHandshakeException: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target

From what I understand about the errors, they're thrown when Java can't validate the certificate provided by the server. However, as I mentioned above, Google Chrome has no problems navigating to the page, and it even verifies the certificate (no security errors are thrown).

Is there a way I can override Java and allow it to receive the response anyway?

回答1:

I think the ip you are trying to access is using the self signed certificate. Try the following two links.

How can I use different certificates on specific connections?

Using Self Signed certificate in java