findElement by cssSelector in Selenium Java - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ locator

intermediate

Identify the correct CSS selector to find a button with class 'submit-btn' inside a form with id 'loginForm'

Which CSS selector will correctly locate the submit button inside the form with id 'loginForm'?

A form#loginForm > button.submit-btn

B .submit-btn #loginForm

C #loginForm .submit-btn

D button#loginForm.submit-btn

💡 Hint

Remember that the selector should find an element with class inside the form with the given id.

The selector #loginForm .submit-btn finds any element with class submit-btn inside the element with id loginForm. Option C looks for an element with id inside a class, which is incorrect. Option C looks for a direct child button which may not always be correct if the button is nested deeper. Option C looks for a button with id 'loginForm' which is wrong.

❓ Predict Output

intermediate

What happens in this Selenium Java code snippet?

Given the following code, what will happen if no such element exists?

Selenium Java

WebElement element = driver.findElement(By.cssSelector("div.content > p.highlight"));
System.out.println(element.getText());

A Prints the text inside the first <p> with class 'highlight' inside a <div> with class 'content'

B Throws NoSuchElementException if no such element exists

C Prints the HTML of the <p> element

D Prints the tag name 'p'

💡 Hint

Consider what happens if the element is not found by findElement.

The findElement method throws NoSuchElementException if the element is not found. The code tries to print the text of the element, but if the element does not exist, it will not reach the print statement and instead throw an exception.

❓ assertion

advanced

Which assertion correctly verifies the presence of an element found by CSS selector?

You want to assert that an element with CSS selector '.nav-item.active' is displayed on the page. Which assertion is correct?

Selenium Java

WebElement element = driver.findElement(By.cssSelector(".nav-item.active"));

A assertFalse(element.isEnabled());

B assertEquals(element.getText(), "true");

C assertNotNull(driver.findElement(By.cssSelector(".nav-item.active")));

D assertTrue(element.isDisplayed());

💡 Hint

Check which method confirms the element is visible on the page.

element.isDisplayed() returns true if the element is visible. Using assertTrue with this method correctly asserts visibility. Option D wrongly compares text to "true". Option D only checks element is not null but does not confirm visibility. Option D asserts the element is disabled, which is unrelated.

🔧 Debug

advanced

Why does this CSS selector cause NoSuchElementException?

Given the HTML structure:

<ul id="menu">
  <li class="item">Home</li>
  <div>
    <li class="item active">About</li>
  </div>
</ul>

The code below throws NoSuchElementException. Why?

driver.findElement(By.cssSelector("ul#menu > li.active"));

A Because the selector should be "ul#menu li.active" without the > combinator

B Because the selector is correct but the element is not visible

C Because the id selector #menu is invalid

D Because the selector looks for a direct child <li> with class 'active', but the <li> has classes 'item active' and the space causes mismatch

💡 Hint

Check the relationship between

and
• elements and the meaning of > in CSS selectors.

The selector ul#menu > li.active looks for

elements with class 'active' that are direct children of

. In the HTML, the
• elements have classes 'item active', so the selector matches. However, if the
• is not a direct child (e.g., wrapped in another element), it won't match. If the
• is direct child, the selector is correct. But if the selector causes NoSuchElementException, likely the
• is not direct child or the selector is too strict. Using ul#menu li.active matches any descendant
• with class 'active'.

❓ framework

expert

How to implement a reusable method to find elements by CSS selector with timeout in Selenium Java?

You want to create a method that waits up to a given timeout for an element to be present using a CSS selector. Which implementation is correct?

A

public WebElement waitForElement(By selector, int timeoutSeconds) {
  WebDriverWait wait = new WebDriverWait(driver, Duration.ofSeconds(timeoutSeconds));
  return wait.until(ExpectedConditions.presenceOfElementLocated(selector));
}

B

public WebElement waitForElement(String cssSelector, int timeoutSeconds) {
  WebDriverWait wait = new WebDriverWait(driver, Duration.ofSeconds(timeoutSeconds));
  return wait.until(ExpectedConditions.elementToBeClickable(By.cssSelector(cssSelector)));
}

C

public WebElement waitForElement(String cssSelector, int timeoutSeconds) {
  WebDriverWait wait = new WebDriverWait(driver, timeoutSeconds);
  return wait.until(ExpectedConditions.visibilityOfElementLocated(By.cssSelector(cssSelector)));
}

D

public WebElement waitForElement(By selector, int timeoutSeconds) {
  WebDriverWait wait = new WebDriverWait(driver, Duration.ofSeconds(timeoutSeconds));
  return wait.until(ExpectedConditions.visibilityOfElementLocated(selector));
}

💡 Hint

Check the correct constructor usage of WebDriverWait and the expected condition for presence.

Option A correctly uses Duration.ofSeconds(timeoutSeconds) for the timeout and waits for presence of element located by the given selector. Option A uses an outdated constructor without Duration, which is deprecated. Option A waits for element to be clickable, which is more restrictive than presence. Option A waits for visibility, which may fail if element is present but hidden.