findElement by ID in Selenium Java

Introduction

We use findElement by ID to quickly find a single web page element using its unique ID. This helps us interact with that element in tests.

When you want to click a button with a unique ID on a webpage.

When you need to enter text into a text box identified by its ID.

When you want to check if a specific element with a known ID is visible.

When you want to verify the content of an element identified by its ID.

When automating form submission where fields have unique IDs.

Syntax

Selenium Java

WebElement element = driver.findElement(By.id("elementID"));

The By.id locator finds the first element with the matching ID attribute.

ID values should be unique on the page for this to work reliably.

Examples

Finds the button with ID loginBtn to click or check.

Selenium Java

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

Finds the username input box by its ID username.

Selenium Java

WebElement usernameField = driver.findElement(By.id("username"));

Finds an error message element by its ID error-msg to verify its text.

Selenium Java

WebElement errorMessage = driver.findElement(By.id("error-msg"));

Sample Program

This test opens a login page, enters username and password by locating inputs with their IDs, clicks the login button, then checks if the success message with a specific ID appears with expected text.

Selenium Java

import org.openqa.selenium.By;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.WebElement;
import org.openqa.selenium.chrome.ChromeDriver;

public class FindElementByIdExample {
    public static void main(String[] args) {
        System.setProperty("webdriver.chrome.driver", "path/to/chromedriver");
        WebDriver driver = new ChromeDriver();
        try {
            driver.get("https://example.com/login");

            // Find username input by ID and enter text
            WebElement username = driver.findElement(By.id("username"));
            username.sendKeys("testuser");

            // Find password input by ID and enter text
            WebElement password = driver.findElement(By.id("password"));
            password.sendKeys("mypassword");

            // Find login button by ID and click
            WebElement loginBtn = driver.findElement(By.id("loginBtn"));
            loginBtn.click();

            // Verify login success message by ID
            WebElement successMsg = driver.findElement(By.id("successMsg"));
            String message = successMsg.getText();
            if (message.equals("Login successful")) {
                System.out.println("Test Passed: Login success message found.");
            } else {
                System.out.println("Test Failed: Unexpected message: " + message);
            }
        } finally {
            driver.quit();
        }
    }
}

Important Notes

Always ensure the ID you use is unique on the page to avoid unexpected results.

If the element with the given ID is not found, Selenium throws a NoSuchElementException.

Use explicit waits if the element may take time to appear before interacting.

Summary

findElement by ID locates a single element using its unique ID attribute.

It is fast and reliable when IDs are unique and stable.

Use it to interact with buttons, inputs, or any element with a known ID.

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