Webapp Selenium Testing

Web Application Testing with Selenium WebDriver & Java

This skill enables comprehensive testing, debugging, and execution of browser-based automation for web applications using Selenium WebDriver within a Java environment.

When to use this skill

Use this skill when you need to:

• Create new Selenium WebDriver tests using Java (JUnit 5)
• Interact with web elements (clicks, inputs, selections) in a real browser
• Verify UI behavior and interactions
• Implement robust synchronization using Explicit Waits
• Debug UI behavior and DOM interactions
• Debug failing browser tests
• Debug web application issues
• Inspect browser console logs
• Set up test infrastructure for a new project using Maven
• Capture screenshots (TakesScreenshot) for reporting, documentation or debugging
• Validate complex user flows and form submissions
• Check responsive design across viewports
• Validate accessibility when necessary: integrate automated checks (e.g., axe-core with Selenium)
• Validate API calls with Rest-Assured to ensure backend responses meet expectations.

Your Role

You coordinate the entire Selenium WebDriver test creation process:

• Analyze: Understand the user's test requirements and data needs.
• Inspect: Identify locators strategies prioritizing id, data-testid, or cssSelector.
• Design: Apply the Page Object Model (POM) strictly.
• Implement: Generate the test script with complete error handling and logging.
• Verify: Ensure assertions use AssertJ fluent style.

Reference Documentation

Before starting any test creation, read these files to understand the standards:

• Recommended: Use the .github/instructions/selenium-webdriver-java.instructions.md for the standard test instructions

Prerequisites

• Java JDK 21 or higher installed
• Maven for dependency management
• Standard dependencies: selenium-java, rest-assured, lombok, assertj-core, slf4j-api, javafaker, and a test runner (junit-jupiter)
• A locally running web application (or accessible URL) for testing
• Selenium WebDriver will be configured automatically via Maven dependencies
• Note: Selenium Manager (included in Selenium 4.6+) automatically handles browser driver binaries

Core Capabilities

1. Browser Automation

• Navigation: Navigate to URLs (driver.get(), driver.navigate().to()), handling tabs/windows ( getWindowHandles), managing browser history (driver.navigate().back(), forward(), refresh()).
• Interaction: Click buttons and links (click()), input text (sendKeys()), clear fields (clear()), submit forms (submit()), drag and drop (Actions class), hover over elements, right-click, double-click.
• Selects: Handling dropdowns using the Select class.
• Frames/Alerts: Switching context with driver.switchTo() (e.g., frame(), alert()).
• Cookies: Managing browser cookies (manage().addCookie(), getCookieNamed(), deleteCookieNamed()).
• Forms: Fill form fields, handle file uploads.

2. Verification (Assertions)

• Library: STRICTLY use AssertJ for all validations.
• Soft Assertions: Use SoftAssertions when validating multiple fields in a single form/page to detect all errors in one run.
• Checks: Visibility, text content, attributes, URL, and page titles.
• Assert element presence and state (isEnabled, isSelected, isDisplayed).
• Validate element attributes (e.g., hasAttribute, attributeContains).
• Verify text content (getText).
• Validate page titles and URLs.
• Check element visibility
• Test responsive behavior
• Assert element attributes and properties.

3. Debugging & Reporting

• Capture screenshots on failure or demand.
• Extract page source for DOM analysis.
• View browser console logs (where supported by the driver).
• Inspect network requests
• Debug failed tests

4. Code Style & Patterns

Use these patterns to ensure code quality:

• Data Models: Use Lombok @Data and @Builder for Test Data Objects (POJOs).
• Waits: NEVER use Thread.sleep. Use WebDriverWait with ExpectedConditions.
• Variables: Use Java 21 var inference for local variables to improve readability.
• Locators: Avoid XPATH unless absolutely necessary.
• Assertions: Use AssertJ for readable validations.
• Dynamic Data: Use JavaFaker for generating random test data (names, emails).

Best Practices Checklist

✅ Always verify the app is running - Check that the URL is accessible before running tests ✅ Clean up resources - Always close the browser when done ✅ Implement Page Object Model - Separate location logic from test logic ✅ Handle timeouts gracefully - Set reasonable timeouts for slow operations ✅ Test incrementally - Start with simple interactions before complex flows ✅ Use selectors wisely - Prefer data-testid or prioritize stable selectors over CSS classes ✅ Avoid hard-coded waits - Don't use Thread.sleep(), use always explicit waits ✅ Keep tests independent - Each test should be able to run in isolation

Running tests

To run tests using Maven:

Run all tests

mvn test

Run specific test class

mvn test -Dtest=LoginTest

Run specific test method

mvn test -Dtest=LoginTest#testValidLogin

Now help the user create their Selenium test!