Window handles (getWindowHandles) in Selenium Java - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

What is the output of getWindowHandles() after opening a new tab?

Consider the following Selenium Java code snippet:

WebDriver driver = new ChromeDriver();
driver.get("https://example.com");
String originalHandle = driver.getWindowHandle();
((JavascriptExecutor)driver).executeScript("window.open('https://google.com','_blank');");
Set<String> handles = driver.getWindowHandles();
System.out.println(handles.size());

What will be printed?

Selenium Java

WebDriver driver = new ChromeDriver();
driver.get("https://example.com");
String originalHandle = driver.getWindowHandle();
((JavascriptExecutor)driver).executeScript("window.open('https://google.com','_blank');");
Set<String> handles = driver.getWindowHandles();
System.out.println(handles.size());

A 1

B 0

C 2

D Throws NoSuchWindowException

💡 Hint

Remember that getWindowHandles() returns all open windows and tabs.

Initially, there is one window. After opening a new tab, there are two windows/tabs. So getWindowHandles() returns a set of size 2.

❓ assertion

intermediate

Which assertion correctly verifies the number of open windows?

You want to assert that exactly three browser windows are open after some actions. Which assertion is correct?

Selenium Java

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

A assertNull(handles.size() - 3);

B assertEquals(3, handles.size());

C assertFalse(handles.size() != 3);

D assertTrue(handles.size() == 3);

💡 Hint

Use the assertion that clearly compares expected and actual values.

assertEquals(3, handles.size()); directly checks that the size is 3. Option B also works logically but is less clear. Option B is invalid because handles.size() - 3 is an int, never null.

🔧 Debug

advanced

Why does switching to a window handle cause NoSuchWindowException?

Given this code snippet:

Set<String> handles = driver.getWindowHandles();
for (String handle : handles) {
    driver.switchTo().window(handle);
    driver.close();
}
driver.switchTo().window(handles.iterator().next());

Why does the last line throw NoSuchWindowException?

A Because all windows were closed in the loop, so the handle is invalid.

B Because <code>handles.iterator().next()</code> returns null after closing windows.

C Because <code>switchTo()</code> requires a frame, not a window handle.

D Because <code>driver.close()</code> does not close windows, only tabs.

💡 Hint

Think about what happens to window handles after closing windows.

The loop closes all windows, so no window handles remain valid. Trying to switch to any handle after closing all windows causes NoSuchWindowException.

🧠 Conceptual

advanced

What is the main difference between getWindowHandle() and getWindowHandles()?

Choose the best explanation:

A <code>getWindowHandle()</code> returns the handle of the current window; <code>getWindowHandles()</code> returns handles of all open windows/tabs.

B <code>getWindowHandle()</code> returns all window handles; <code>getWindowHandles()</code> returns the current window handle.

C Both methods return the same set of window handles.

D <code>getWindowHandle()</code> returns handles of all frames; <code>getWindowHandles()</code> returns handles of all windows.

💡 Hint

Think about singular vs plural in the method names.

getWindowHandle() returns a single String for the current window. getWindowHandles() returns a Set of Strings for all open windows/tabs.

❓ framework

expert

How to safely switch to a newly opened window in Selenium Java?

You have a test that opens a new window. Which code snippet correctly switches to the new window without errors?

Selenium Java

String originalHandle = driver.getWindowHandle();
// code that opens new window
Set<String> allHandles = driver.getWindowHandles();

A driver.switchTo().frame(allHandles.iterator().next());

B driver.switchTo().window(allHandles.iterator().next());

C driver.switchTo().window(originalHandle);

D

for (String handle : allHandles) {
  if (!handle.equals(originalHandle)) {
    driver.switchTo().window(handle);
    break;
  }
}

💡 Hint

Remember to avoid switching back to the original window.

Option D loops through all handles and switches to the one that is not the original. Option D may switch back to the original window. Option D switches to the original window, not the new one. Option D tries to switch to a frame using a window handle, causing an error.