How do you take a screenshot when a test fails in Selenium?

Answer

Auto-Screenshot on Test Failure

Capturing screenshots on failure helps identify exactly what the browser showed when the test broke — crucial for debugging in CI/CD.

Method 1 — TestNG @AfterMethod (Simple)

Java

import org.openqa.selenium.TakesScreenshot;
import org.openqa.selenium.OutputType;
import org.apache.commons.io.FileUtils;
import org.testng.ITestResult;
import java.io.File;

@AfterMethod
public void captureScreenshotOnFailure(ITestResult result) throws Exception {
    if (result.getStatus() == ITestResult.FAILURE) {
        TakesScreenshot ts = (TakesScreenshot) driver;
        File src  = ts.getScreenshotAs(OutputType.FILE);
        String timestamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());
        String path = "screenshots/" + result.getName() + "_" + timestamp + ".png";
        FileUtils.copyFile(src, new File(path));
        System.out.println("Screenshot saved: " + path);
    }
}

Method 2 — TestNG ITestListener (Framework-Level)

Java

public class ScreenshotListener implements ITestListener {

    @Override
    public void onTestFailure(ITestResult result) {
        WebDriver driver = DriverManager.getDriver(); // get driver from ThreadLocal
        TakesScreenshot ts = (TakesScreenshot) driver;
        byte[] screenshot = ts.getScreenshotAs(OutputType.BYTES);

        // Attach to Extent Report
        ExtentReportManager.getTest().addScreenCaptureFromBase64String(
            Base64.getEncoder().encodeToString(screenshot),
            "Failure Screenshot"
        );
    }
}

XML

<listeners>
    <listener class-name="listeners.ScreenshotListener"/>
</listeners>

Method 3 — Save with Timestamp

Java

public static String captureScreenshot(WebDriver driver, String testName) {
    String timestamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());
    String screenshotPath = "test-output/screenshots/" + testName + "_" + timestamp + ".png";

    File src  = ((TakesScreenshot) driver).getScreenshotAs(OutputType.FILE);
    File dest = new File(screenshotPath);
    try {
        FileUtils.copyFile(src, dest);
    } catch (IOException e) {
        e.printStackTrace();
    }
    return screenshotPath;
}

Best Practices

✓Always name screenshots with test name + timestamp to avoid overwrites
✓Save to a dedicated screenshots/ folder tracked by CI artifacts
✓Attach screenshots to ExtentReports or Allure for visual reports
✓Use Base64 encoding to embed screenshots directly in HTML reports
✓Take screenshot before driver.quit() in @AfterMethod