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

Challenge - 5 Problems

❓ Predict Output

intermediate

What is the output of this Selenium Java code snippet?

Consider the following Selenium Java code that tries to find an element by ID and print its text. What will be printed if the element with ID "submitBtn" contains the text "Submit"?

Selenium Java

WebElement button = driver.findElement(By.id("submitBtn"));
System.out.println(button.getText());

A Submit

B submitBtn

C null

D NoSuchElementException

💡 Hint

The getText() method returns the visible text of the element.

The findElement(By.id("submitBtn")) locates the element with ID 'submitBtn'. Calling getText() on this element returns its visible text, which is 'Submit'.

❓ assertion

intermediate

Which assertion correctly verifies the text of an element found by ID?

You want to verify that the element with ID "welcomeMsg" contains the text "Welcome User". Which assertion is correct in JUnit?

Selenium Java

WebElement message = driver.findElement(By.id("welcomeMsg"));

A assertFalse(message.getText().equals("Welcome User"));

B assertTrue(message.getText() == "Welcome User");

C assertEquals("Welcome User", message.getText());

D assertNull(message.getText());

💡 Hint

Use assertEquals to compare strings in JUnit.

assertEquals(expected, actual) correctly compares the expected string with the actual text. Using '==' compares references, which is incorrect for strings.

❓ locator

advanced

Which locator correctly finds an element by ID in Selenium Java?

You want to find an element with the ID "loginInput". Which locator code is correct?

A driver.findElement(By.id("loginInput"));

B driver.findElement(By.name("loginInput"));

C driver.findElement(By.className("loginInput"));

D driver.findElement(By.tagName("loginInput"));

💡 Hint

ID is unique and located with By.id.

By.id("loginInput") finds the element with the exact ID. Other locators search by different attributes or tags.

🔧 Debug

advanced

What error occurs if findElement(By.id) does not find any element?

If the element with ID "nonExistent" is not present on the page, what happens when this code runs? WebElement elem = driver.findElement(By.id("nonExistent"));

Selenium Java

WebElement elem = driver.findElement(By.id("nonExistent"));

A NullPointerException

B NoSuchElementException

C TimeoutException

D ElementNotVisibleException

💡 Hint

findElement throws an exception if no element is found.

findElement throws NoSuchElementException immediately if the element is not found. It does not return null.

❓ framework

expert

In a Selenium Java test framework, which method best waits for an element by ID before interacting?

You want to wait up to 10 seconds for an element with ID "submitBtn" to be clickable before clicking it. Which code snippet correctly uses WebDriverWait?

A driver.findElement(By.id("submitBtn")).click();

B driver.manage().timeouts().implicitlyWait(Duration.ofSeconds(10)); driver.findElement(By.id("submitBtn")).click();

C Thread.sleep(10000); driver.findElement(By.id("submitBtn")).click();

D new WebDriverWait(driver, Duration.ofSeconds(10)).until(ExpectedConditions.elementToBeClickable(By.id("submitBtn"))).click();

💡 Hint

Explicit waits wait for specific conditions before proceeding.

Option D uses explicit wait with WebDriverWait and ExpectedConditions to wait until the element is clickable, then clicks it. Option D clicks immediately and may fail if element not ready. Option D uses fixed sleep which is inefficient. Option D sets implicit wait but does not wait for clickability.

Practice

1. What does the Selenium method findElement(By.id("submitBtn")) do?

easy

A. Finds elements by their tag name "submitBtn".

B. Finds the first element on the page with the ID "submitBtn".

C. Finds elements by their class name "submitBtn".

D. Finds all elements with the ID "submitBtn".

Solution

1. Step 1: Understand the method purpose

   The method findElement locates a single web element on the page.

2. Step 2: Analyze the locator used

   Using By.id("submitBtn") means it looks for an element with the exact ID "submitBtn".

3. Final Answer:

   Finds the first element on the page with the ID "submitBtn". -> Option B

4. Quick Check:

   findElement + By.id = single element by ID [OK]

Hint: findElement(By.id) always returns one element by unique ID [OK]

Common Mistakes:

• Confusing findElement with findElements (plural)
• Using class name or tag name instead of ID
• Assuming it returns multiple elements

2. Which of the following is the correct syntax to find an element with ID "username" in Selenium Java?

easy

A. driver.findElement(By.id="username");

B. driver.findElement(By.Id("username"));

C. driver.findElement(By.ID("username"));

D. driver.findElement(By.id("username"));

Solution

1. Step 1: Recall correct method syntax

   The method By.id is called with parentheses and a string argument, like By.id("username").

2. Step 2: Check Java case sensitivity

   Java is case-sensitive, so By.id must be lowercase 'id', and parentheses are required.

3. Final Answer:

   driver.findElement(By.id("username")); -> Option D

4. Quick Check:

   Correct method call syntax = driver.findElement(By.id("username")); [OK]

Hint: Use By.id("value") with parentheses and lowercase 'id' [OK]

Common Mistakes:

• Using assignment '=' instead of parentheses
• Wrong capitalization like By.ID or By.Id
• Missing parentheses around the ID string

3. What will happen when the following code runs if no element with ID "loginBtn" exists on the page?

WebElement button = driver.findElement(By.id("loginBtn"));
button.click();

medium

A. Throws NoSuchElementException at findElement line.

B. Throws NullPointerException at button.click().

C. The code clicks the button successfully.

D. Returns null and skips the click.

Solution

1. Step 1: Understand findElement behavior when element missing

   If no element matches the ID, findElement throws NoSuchElementException immediately.

2. Step 2: Analyze code flow

   The exception occurs at the findElement line, so button.click() is never reached.

3. Final Answer:

   Throws NoSuchElementException at findElement line. -> Option A

4. Quick Check:

   Missing element causes NoSuchElementException [OK]

Hint: findElement throws exception if ID not found, no null returned [OK]

Common Mistakes:

• Assuming findElement returns null if element missing
• Expecting NullPointerException instead
• Thinking click() runs even if element not found

4. Identify the error in this Selenium Java code snippet:

WebElement input = driver.findElement(By.id("email"));
input.sendKeys("[e-mail]");
WebElement submit = driver.findElement(By.id("submit"));
submit.click();

Assuming the page has no element with ID "submit".

medium

A. Throws ElementNotInteractableException at sendKeys line.

B. No error; code runs fine.

C. Throws NoSuchElementException at finding "submit" element.

D. Throws StaleElementReferenceException at click line.

Solution

1. Step 1: Check element existence for each findElement

   The element with ID "email" exists, so sendKeys works fine.

2. Step 2: Analyze finding "submit" element

   Since "submit" ID does not exist, findElement(By.id("submit")) throws NoSuchElementException.

3. Final Answer:

   Throws NoSuchElementException at finding "submit" element. -> Option C

4. Quick Check:

   Missing ID causes NoSuchElementException [OK]

Hint: Missing ID in findElement causes NoSuchElementException [OK]

Common Mistakes:

• Assuming sendKeys fails if element missing later
• Confusing exceptions thrown at different lines
• Expecting click() to throw error instead of findElement

5. You want to fill a form field with ID "userEmail" and then click a button with ID "submitBtn". Which code snippet correctly handles the possibility that the button might not be present, avoiding test failure?

hard

A. driver.findElement(By.id("userEmail")).sendKeys("[e-mail]");
try {
driver.findElement(By.id("submitBtn")).click();
} catch (NoSuchElementException e) {
System.out.println("Button not found, skipping click.");
}

B. driver.findElement(By.id("userEmail")).sendKeys("[e-mail]");
WebElement btn = driver.findElement(By.id("submitBtn"));
if(btn != null) {
btn.click();
}

C. driver.findElement(By.id("userEmail")).sendKeys("[e-mail]");
driver.findElement(By.id("submitBtn")).click();

D. driver.findElement(By.id("userEmail")).sendKeys("[e-mail]");
WebElement btn = null;
btn.click();

Solution

1. Step 1: Understand the problem

   The button with ID "submitBtn" might not exist, so clicking it directly may cause an exception.

2. Step 2: Evaluate each option

   driver.findElement(By.id("userEmail")).sendKeys("[e-mail]"); driver.findElement(By.id("submitBtn")).click(); clicks without checking, risking failure. driver.findElement(By.id("userEmail")).sendKeys("[e-mail]"); WebElement btn = driver.findElement(By.id("submitBtn")); if(btn != null) { btn.click(); } attempts null check but throws NoSuchElementException at findElement since it never returns null. driver.findElement(By.id("userEmail")).sendKeys("[e-mail]"); try { driver.findElement(By.id("submitBtn")).click(); } catch (NoSuchElementException e) { System.out.println("Button not found, skipping click."); } uses try-catch to handle missing button gracefully. driver.findElement(By.id("userEmail")).sendKeys("[e-mail]"); WebElement btn = null; btn.click(); assigns null and calls click(), causing NullPointerException.

3. Final Answer:

   Use try-catch to handle missing element and avoid failure. -> Option A

4. Quick Check:

   Try-catch handles missing element safely [OK]

Hint: Use try-catch to handle missing elements safely [OK]

Common Mistakes:

• Not handling missing elements causing test failure
• Calling click() on null element
• Assuming findElement returns null if element is missing