How to switch window using Selenium

Selenium provides the function windowhandle for the driver. this functions can be used to find out all the available windows in a driver and then can be switched if it is different from the previously opened window.

Below is the logic which i have used:

String a = driver.getWindowHandle();

Set<String> b = driver.getWindowHandles();

if(b.size() > 1){
for(String windowHandle  : b)
       {
if(windowHandle.equals(a))
{
       //Do Nothing
}
else
{
driver.switchTo().window(windowHandle);
}

       }