try the below code.. it worked for me...
public static void main(String[] args)
{
System.setProperty("webdriver.chrome.driver", "./drivers/chromedriver.exe");
WebDriver driver = new ChromeDriver();
driver.manage().window().maximize();
driver.manage().timeouts().implicitlyWait(10, TimeUnit.SECONDS);
driver.get("https://www.naukri.com/");
//Get the address of main window
String p = driver.getWindowHandle();
//get address of all windows
Set allWH = driver.getWindowHandles();
//get address of all windows and store it in ArrayList
ArrayList allWHCopy = new ArrayList(allWH);
//close the 2nd window
for(int i=0;i