findElement by className in Selenium Java - Cheat Sheet & Quick Revision

Recall & Review

beginner

What does findElement(By.className("className")) do in Selenium?

It finds the first web element on the page that has the specified CSS class name.

intermediate

Why should you avoid using findElement(By.className()) with multiple classes separated by spaces?

Because <code>By.className</code> accepts only a single class name, not multiple classes separated by spaces. Using multiple classes will cause an error.

beginner

How do you handle the situation if findElement(By.className()) does not find any matching element?

It throws a NoSuchElementException. You can handle it by using try-catch or by checking if elements exist before accessing.

beginner

Write a simple Java code snippet using Selenium to find an element by class name "button-primary" and click it.

WebElement button = driver.findElement(By.className("button-primary")); button.click();

intermediate

What is a better alternative locator if you want to find an element with multiple classes?

Use By.cssSelector with a CSS selector combining classes, e.g., By.cssSelector(".class1.class2").

What will happen if you use findElement(By.className("btn primary")) in Selenium?

A It throws an error because multiple classes are not allowed.

B It finds the element with class name 'btn primary' as a single class.

C It finds the element with both classes 'btn' and 'primary'.

D It returns null without error.

By.className accepts only a single class name without spaces. Using multiple classes separated by spaces causes an error.

Which Selenium method is best to find an element by a single CSS class?

A findElement(By.xpath())

B findElement(By.id())

C findElement(By.tagName())

D findElement(By.className())

By.className is designed to find elements by a single CSS class.

If findElement(By.className("menu")) finds multiple elements, which one is returned?

A All elements with class 'menu'.

B The first element with class 'menu'.

C A random element with class 'menu'.

D No element, it throws an exception.

findElement returns the first matching element found in the DOM.

What exception does Selenium throw if findElement(By.className()) finds no element?

A NoSuchElementException

B ElementNotVisibleException

C TimeoutException

D StaleElementReferenceException

NoSuchElementException is thrown when no matching element is found.

Which locator is better to find an element with multiple classes 'btn' and 'active'?

A By.className("btn active")

B By.tagName("btn active")

C By.cssSelector(".btn.active")

D By.id("btn active")

By.cssSelector with combined classes is the correct way to find elements with multiple classes.

Explain how to use findElement(By.className()) in Selenium and mention its limitations.

Think about how CSS classes work and Selenium's locator rules.

Describe how you would handle a situation where findElement(By.className()) does not find any element during test execution.

Consider exception handling best practices in Selenium.

Practice

1. What does the Selenium method findElement(By.className("btn-primary")) do in a test script?

easy

A. It finds an element by its HTML tag name "btn-primary".

B. It finds all web elements with the CSS class "btn-primary" on the page.

C. It finds the first web element with the CSS class "btn-primary" on the page.

D. It finds an element by its ID "btn-primary".

Solution

1. Step 1: Understand the method purpose

   The method findElement locates a single element on the page.

2. Step 2: Analyze the locator type

   Using By.className("btn-primary") targets elements with the CSS class "btn-primary".

3. Final Answer:

   It finds the first web element with the CSS class "btn-primary" on the page. -> Option C

4. Quick Check:

   findElement + className = first matching element [OK]

Hint: findElement with className returns first matching element [OK]

Common Mistakes:

• Confusing findElement with findElements (plural)
• Using className to find by ID or tag
• Expecting multiple elements returned

2. Which of the following is the correct syntax to find an element by class name "login-button" in Selenium Java?

easy

A. driver.findElement(By.classname("login-button"));

B. driver.findElement(By.className("login-button"));

C. driver.findElement(By.class_name("login-button"));

D. driver.findElement(By.class("login-button"));

Solution

1. Step 1: Recall correct method usage

   The correct method to locate by class name is By.className() with capital N.

2. Step 2: Check syntax correctness

   driver.findElement(By.className("login-button")); uses the exact correct syntax: By.className("login-button").

3. Final Answer:

   driver.findElement(By.className("login-button")); -> Option B

4. Quick Check:

   Correct method name is className with capital N [OK]

Hint: Use By.className with capital N for correct syntax [OK]

Common Mistakes:

• Using By.class instead of By.className
• Wrong method casing like class_name or classname
• Missing quotes around class name

3. Given the HTML snippet:

<button class="submit-btn primary">Submit</button>

What will the following code return?

WebElement btn = driver.findElement(By.className("primary"));
System.out.println(btn.getText());

medium

A. Submit

B. primary

C. submit-btn

D. NoSuchElementException

Solution

1. Step 1: Locate element by class name "primary"

   The button has class "primary" among others, so it matches.

2. Step 2: Get the text of the found element

   The getText() method returns the visible text inside the button, which is "Submit".

3. Final Answer:

   Submit -> Option A

4. Quick Check:

   findElement by className finds element, getText returns inner text [OK]

Hint: getText() returns visible text inside found element [OK]

Common Mistakes:

• Expecting class name as text output
• Confusing class attribute with element text
• Assuming exception if multiple classes present

4. What is wrong with this Selenium Java code snippet?

WebElement element = driver.findElement(By.className("btn primary"));

It tries to find an element with classes "btn" and "primary".

medium

A. The syntax is correct; it finds elements with both classes.

B. It should use findElements instead of findElement.

C. It should use By.id instead of By.className.

D. className locator cannot contain spaces; it matches only one class.

Solution

1. Step 1: Understand className locator rules

   The By.className locator accepts only a single class name without spaces.

2. Step 2: Identify the error in locator usage

   Using "btn primary" with space is invalid and causes an error; it cannot find elements with multiple classes this way.

3. Final Answer:

   className locator cannot contain spaces; it matches only one class. -> Option D

4. Quick Check:

   className accepts single class only, no spaces [OK]

Hint: Use single class name without spaces in className locator [OK]

Common Mistakes:

• Trying to find multiple classes with space-separated string
• Expecting findElement to accept compound class selectors
• Confusing className with CSS selector syntax

5. You want to click the first button with class "nav-item active" on a page. Which is the best way to do this using Selenium Java?

hard

A. driver.findElement(By.cssSelector(".nav-item.active")).click();

B. driver.findElement(By.className("nav-item active")).click();

C. driver.findElement(By.className("nav-item")).click();

D. driver.findElement(By.xpath("//button[@class='nav-item active']")).click();

Solution

1. Step 1: Understand limitation of className locator

   The By.className locator cannot handle multiple classes separated by spaces.

2. Step 2: Use CSS selector for multiple classes

   The CSS selector .nav-item.active matches elements with both classes and works correctly.

3. Step 3: Compare other options

   driver.findElement(By.className("nav-item active")).click(); is invalid due to space in className; driver.findElement(By.className("nav-item")).click(); matches only one class; driver.findElement(By.xpath("//button[@class='nav-item active']")).click(); uses XPath but is less concise.

4. Final Answer:

   driver.findElement(By.cssSelector(".nav-item.active")).click(); -> Option A

5. Quick Check:

   Use CSS selector for multiple classes, not className [OK]

Hint: Use CSS selector for multiple classes, not className [OK]

Common Mistakes:

• Using className with multiple classes separated by space
• Using only one class when both are needed
• Ignoring CSS selectors as a better alternative