Validate Html example in selenium script

Question

I'm writing an automated test framework where after each action (loading a new page etc) I want to validate the html that is produced. I am writing the framework in java and the tests may be run in an environment which is sitting behind a firewall etc.

I currently have the html in string format so I am looking for a way to verify that the html in the string is valid. I was looking at jTidy but I can't find a good example of how to do this. Does anyone have any idea?

Also further down the track I might look at validating the css files, so if suggestions could take that into consideration.

Thanks in advance, James

Edit:

I have something working in JTidy now, hoping someone more knowlegable can verify it. How can I print out the errors from it?

tidy = new Tidy();
    ByteArrayOutputStream os = new ByteArrayOutputStream();
    String html = ScenarioFramework.driver.getHtml();
    try {
        Node node = tidy.parse(new ByteArrayInputStream(html.getBytes("UTF-8")), os);
    } catch (UnsupportedEncodingException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
        return false;
    } 

    if ((tidy.getParseErrors() > 0) || (tidy.getParseWarnings() > 0)) { 

        System.out.println("Tidy Parser errors: " + tidy.getParseErrors());
        System.out.println("Tidy Parser warnings: " + tidy.getParseWarnings());
        return false;
    } else{
        //return with no error
        return true;
    }

Answer 1

Depending on how good you want the validation to be. I've seen someone integrate their tests with http://validator.w3.org/docs/api.html ... just by doing HTTP posts to the service I believe. Would give more details that jTidy.

They also have the equivalent for CSS.

Sorry, but I don't have the code, just a demo I saw once that I thought would be cool to emulate some day.

Be nice to the service though ... you might want to avoid validating if you can tell the HTML hasn't changed.