ProxyServer proxy = new ProxyServer(4444);
proxy.start();
// configure it as a desired capability
DesiredCapabilities capabilities = new DesiredCapabilities();
capabilities.setCapability(CapabilityType.PROXY, proxy.seleniumProxy());
FirefoxDriver driver = new FirefoxDriver(capabilities);
driver.manage().timeouts().implicitlyWait(10, TimeUnit.SECONDS);
// start capture