How do we configure proxy to our browser?

If we need to use a proxy. How do we configure that?

Proxy configuration is done via the org.openqa.selenium.Proxy class like so:

Proxy settings need to set, when an application runs under proxy. And also we can set

the Desired Capabilities for any given browser. 

Proxy proxy = new Proxy();
proxy.setProxyAutoconfigUrl("http://youdomain/config");
// We use firefox as an example here.
DesiredCapabilities capabilities = DesiredCapabilities.firefox();
capabilities.setCapability(CapabilityType.PROXY, proxy);
// You could use any webdriver implementation here
WebDriver driver = new FirefoxDriver(capabilities);