How to Capture Screenshots for Failed Test Cases in Selenium

Before you start capturing screenshots of failed test cases in automated testing, Understanding Most Common Reasons for Test Case Failures

1. The locator used to find a web element is incorrect or outdated, causing Selenium to be unable to locate the element on the page.

2. The application may not be fully loaded when the test tries to interact with elements, leading toStaleElementReferenceException or NoSuchElementException

3. Updates or changes to the application’s UI or functionality can break existing tests, making them fail unexpectedly.

Capturing screenshots for failed test cases in Selenium WebDriver is essential for debugging and understanding why test cases fail. 

ExampleCode:

import org.openqa.selenium.OutputType;
import org.openqa.selenium.TakesScreenshot;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.chrome.ChromeDriver;
import org.apache.commons.io.FileUtils; // You need Apache Commons IO dependency for this

import java.io.File;
import java.io.IOException;

public class TakeScreenshotForFailedTestCase {

    private WebDriver driver;

    public void setUp() {
        System.setProperty("webdriver.chrome.driver", "/path/to/chromedriver");
        driver = new ChromeDriver();
    }

    public void tearDown() {
        driver.quit();
    }

    public void captureScreenshot(String testName) {
        // Capture screenshot
        File screenshot = ((TakesScreenshot) driver).getScreenshotAs(OutputType.FILE);
        try {
            // Save the screenshot to a specific location
            FileUtils.copyFile(screenshot, new File("screenshots/" + testName + ".png"));
        } catch (IOException e) {
            System.out.println("Failed to save screenshot: " + e.getMessage());
        }
    }

    public void testExample() {
        setUp();
        try {
            driver.get("https://example.com");
            // Simulating a test failure
            if (driver.getTitle().equals("Expected Title")) {
                System.out.println("Test Passed");
            } else {
                throw new Exception("Title did not match");
            }
        } catch (Exception e) {
            System.out.println("Test Failed: " + e.getMessage());
            captureScreenshot("testExample"); // Capture screenshot on failure
        } finally {
            tearDown();
        }
    }

    public static void main(String[] args) {
        TakeScreenshotForFailedTestCase example = new TakeScreenshotForFailedTestCase();
        example.testExample();
    }
}

TakesScreenshot Interface: This interface allows you to capture screenshots in Selenium WebDriver.

OutputType.FILE: Specifies the output type as a file.

Apache Commons IO: The FileUtils.copyFile() method from Apache Commons IO is used to save the screenshot. 

Add dependency 

<dependency>
    <groupId>commons-io</groupId>
    <artifactId>commons-io</artifactId>
    <version>2.8.0</version> <!-- Use the latest version -->
</dependency>

I believe the content of this blog article will be beneficial for your interview success and for enhancing your automation test framework.