How to handle same multiple windows e.g. google in Selenium WebDriver with Java

You can get a handle to your window via driver.getWindowHandle()and you can switch to a window with driver.switchTo().window("handle");.

If you want to open a new window you can click on a link with target="_blank" on the website or execute JavaScript to open a new window. Then you'll find another handle in driver.getWindowHandles(). A possible way could be:

WebDriver driver = new FirefoxDriver();
driver.get("https://www.google.com");
List<String> knownHandles = new ArrayList<String>();
knownHandles.add(driver.getWindowHandle());
((JavascriptExecutor)driver).executeScript("window.open();");
// find the new handle. we are getting a set 
for (String handle : driver.getWindowHandles()) {
    if (!knownHandles.contains(handle)) {
        knownHandles.add(handle);
        break;
    }
}
String newHandle = knownHandles.get(knownHandles.size() -1 );
driver.switchTo().window(newHandle);
driver.get("https://www.google.com");

Another way is to inject the anchor and click it via JavaScript.

//Store the current window handle

String winHandleBefore = driver.getWindowHandle();

//Switch to new window opened

for(String winHandle : driver.getWindowHandles()){
    driver.switchTo().window(winHandle);
}

// Perform the actions on new window

driver.manage().window().maximize();

//Close the new window, if that window no more required

driver.close();

//Switch back to original browser (first window)

driver.switchTo().window(winHandleBefore);

Here is a sample example handling multiple windows:

public class Mytesting {
 WebDriver driver = new FirefoxDriver();

 @Before
 public void beforetest() {
  driver.manage().window().maximize();
  driver.get("http://only-testing-blog.blogspot.in/2014/01/textbox.html");
 }

@Test
  public void test () throws InterruptedException 
  {
  driver.manage().timeouts().implicitlyWait(15, TimeUnit.SECONDS);
  driver.findElement(By.xpath("//b[contains(.,'Open New Page')]")).click();

  // Get and store both window handles in array
  Set<String> AllWindowHandles = driver.getWindowHandles();
  String window1 = (String) AllWindowHandles.toArray()[0];
  System.out.print("window1 handle code = "+AllWindowHandles.toArray()[0]);
  String window2 = (String) AllWindowHandles.toArray()[1];
  System.out.print("\nwindow2 handle code = "+AllWindowHandles.toArray()[1]);

  //Switch to window2(child window) and performing actions on it.
  driver.switchTo().window(window2);
  driver.findElement(By.xpath("//input[@name='fname']")).sendKeys("My Name");
  driver.findElement(By.xpath("//input[@value='Bike']")).click();
  driver.findElement(By.xpath("//input[@value='Car']")).click();
  driver.findElement(By.xpath("//input[@value='Boat']")).click();
  driver.findElement(By.xpath("//input[@value='male']")).click();
  Thread.sleep(5000);

  //Switch to window1(parent window) and performing actions on it.
  driver.switchTo().window(window1);
  driver.findElement(By.xpath("//option[@id='country6']")).click();
  driver.findElement(By.xpath("//input[@value='female']")).click();
  driver.findElement(By.xpath("//input[@value='Show Me Alert']")).click();
  driver.switchTo().alert().accept();
  Thread.sleep(5000);

  //Once Again switch to window2(child window) and performing actions on it.
  driver.switchTo().window(window2);
  driver.findElement(By.xpath("//input[@name='fname']")).clear();
  driver.findElement(By.xpath("//input[@name='fname']")).sendKeys("Name Changed");
  Thread.sleep(5000);
  driver.close();


  //Once Again switch to window1(parent window) and performing actions on it.
  driver.switchTo().window(window1);
  driver.findElement(By.xpath("//input[@value='male']")).click();
  Thread.sleep(5000);

  }