Executing Headless test in Firefox driver

HeadlessFF.java

public static void main(String[] args) throws IOException {

        // Setup firefox binary to start in Xvfb        
        String Xport = System.getProperty(
                "lmportal.xvfb.id", ":1");
        final File firefoxPath = new File(System.getProperty(
                "lmportal.deploy.firefox.path", "/usr/bin/firefox"));
        FirefoxBinary firefoxBinary = new FirefoxBinary(firefoxPath);
        firefoxBinary.setEnvironmentProperty("DISPLAY", Xport);

        // Start Firefox driver
        WebDriver driver = new FirefoxDriver(firefoxBinary, null);
        driver.manage().timeouts().implicitlyWait(30, TimeUnit.SECONDS);
        driver.get("http://google.com/");

        // Take snapshot of browser
        File srcFile = ((TakesScreenshot)driver).getScreenshotAs(OutputType.FILE);
        FileUtils.copyFile(srcFile, new File("ffsnapshot.png"));
        driver.quit();
    }