Test class consuming page objects in Selenium Java - Build an Automation Script

Verify login functionality using page objects

Preconditions (2)

Step 1: Open the browser and navigate to 'https://example.com/login'

Step 2: Enter 'testuser' in the username input field

Step 3: Enter 'Test@1234' in the password input field

Step 4: Click the login button

Step 5: Wait for the dashboard page to load

✅ Expected Result: User is redirected to the dashboard page with URL containing '/dashboard' and a welcome message is displayed

Automation Requirements - Selenium WebDriver with JUnit 5

Assertions Needed:

Verify current URL contains '/dashboard'

Verify welcome message element is displayed and contains text 'Welcome, testuser'

Best Practices:

Use Page Object Model to separate page interactions

Use explicit waits to wait for elements

Use meaningful and stable locators (id, name, or CSS selectors)

Use JUnit 5 assertions

Close browser after test

Automated Solution

Selenium Java

import org.junit.jupiter.api.AfterEach;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;
import org.openqa.selenium.By;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.WebElement;
import org.openqa.selenium.chrome.ChromeDriver;
import org.openqa.selenium.support.ui.ExpectedConditions;
import org.openqa.selenium.support.ui.WebDriverWait;

import java.time.Duration;

import static org.junit.jupiter.api.Assertions.*;

// Page Object for Login Page
class LoginPage {
    private WebDriver driver;
    private WebDriverWait wait;

    private By usernameInput = By.id("username");
    private By passwordInput = By.id("password");
    private By loginButton = By.cssSelector("button[type='submit']");

    public LoginPage(WebDriver driver) {
        this.driver = driver;
        this.wait = new WebDriverWait(driver, Duration.ofSeconds(10));
    }

    public void enterUsername(String username) {
        WebElement userField = wait.until(ExpectedConditions.visibilityOfElementLocated(usernameInput));
        userField.clear();
        userField.sendKeys(username);
    }

    public void enterPassword(String password) {
        WebElement passField = wait.until(ExpectedConditions.visibilityOfElementLocated(passwordInput));
        passField.clear();
        passField.sendKeys(password);
    }

    public void clickLogin() {
        WebElement button = wait.until(ExpectedConditions.elementToBeClickable(loginButton));
        button.click();
    }

    public void loginAs(String username, String password) {
        enterUsername(username);
        enterPassword(password);
        clickLogin();
    }
}

// Page Object for Dashboard Page
class DashboardPage {
    private WebDriver driver;
    private WebDriverWait wait;

    private By welcomeMessage = By.id("welcome-msg");

    public DashboardPage(WebDriver driver) {
        this.driver = driver;
        this.wait = new WebDriverWait(driver, Duration.ofSeconds(10));
    }

    public boolean isWelcomeMessageDisplayed() {
        return wait.until(ExpectedConditions.visibilityOfElementLocated(welcomeMessage)).isDisplayed();
    }

    public String getWelcomeMessageText() {
        return driver.findElement(welcomeMessage).getText();
    }
}

public class LoginTest {
    private WebDriver driver;
    private LoginPage loginPage;
    private DashboardPage dashboardPage;

    @BeforeEach
    public void setUp() {
        driver = new ChromeDriver();
        driver.manage().window().maximize();
        driver.get("https://example.com/login");
        loginPage = new LoginPage(driver);
        dashboardPage = new DashboardPage(driver);
    }

    @Test
    public void testValidLogin() {
        loginPage.loginAs("testuser", "Test@1234");

        // Wait for URL to contain '/dashboard'
        new WebDriverWait(driver, Duration.ofSeconds(10))
                .until(ExpectedConditions.urlContains("/dashboard"));

        assertTrue(driver.getCurrentUrl().contains("/dashboard"), "URL should contain '/dashboard'");
        assertTrue(dashboardPage.isWelcomeMessageDisplayed(), "Welcome message should be displayed");
        assertEquals("Welcome, testuser", dashboardPage.getWelcomeMessageText(), "Welcome message text should match");
    }

    @AfterEach
    public void tearDown() {
        if (driver != null) {
            driver.quit();
        }
    }
}

The code uses the Page Object Model to separate page interactions from the test logic.

LoginPage class handles entering username, password, and clicking login with explicit waits to ensure elements are ready.

DashboardPage class checks for the welcome message presence and text.

The LoginTest class sets up the ChromeDriver, opens the login page, uses the page objects to perform login, then asserts the URL and welcome message.

Explicit waits ensure the test waits for the page to load and elements to appear before interacting or asserting.

Finally, the browser is closed in the tearDown method to clean up.

Common Mistakes - 4 Pitfalls

Using Thread.sleep() instead of explicit waits

Locating elements directly in the test class instead of using page objects

Using brittle locators like absolute XPath

Not closing the browser after tests

Bonus Challenge

Now add data-driven testing with 3 different sets of login credentials (valid and invalid) using JUnit 5 parameterized tests.

Show Hint

Practice

1. What is the main purpose of a test class when it consumes page objects in Selenium Java?

easy

A. To locate web elements directly using Selenium locators

B. To manage browser driver setup and teardown only

C. To define the structure of the web page elements

D. To perform test steps and assertions using methods from page objects

Solution

1. Step 1: Understand roles of test class and page objects

   Page objects encapsulate web element locators and actions. Test classes use these to perform tests.

2. Step 2: Identify test class responsibility

   Test classes call page object methods to execute test steps and verify results with assertions.

3. Final Answer:

   To perform test steps and assertions using methods from page objects -> Option D

4. Quick Check:

   Test class runs tests using page objects [OK]

Hint: Test classes call page object methods to run tests [OK]

Common Mistakes:

• Trying to locate elements directly in test class
• Mixing page object code with test logic
• Using test class only for driver setup

2. Which of the following is the correct way to instantiate a page object in a Selenium Java test class?

easy

A. LoginPage login = new LoginPage(driver);

B. LoginPage login = LoginPage();

C. LoginPage login = new LoginPage();

D. LoginPage login = driver.get(LoginPage.class);

Solution

1. Step 1: Recall page object constructor usage

   Page objects usually require WebDriver passed to constructor for element initialization.

2. Step 2: Check each option for correct syntax

   LoginPage login = new LoginPage(driver); correctly uses 'new' with driver argument. Others miss driver or use invalid syntax.

3. Final Answer:

   LoginPage login = new LoginPage(driver); -> Option A

4. Quick Check:

   Use 'new' with driver parameter [OK]

Hint: Always pass driver to page object constructor [OK]

Common Mistakes:

• Forgetting to pass driver to constructor
• Using constructor without 'new' keyword
• Trying to get page object from driver directly

3. Given the following test class snippet, what will be the output if the login fails?

LoginPage login = new LoginPage(driver);
boolean result = login.login("wrongUser", "wrongPass");
System.out.println(result ? "Login Successful" : "Login Failed");

Assuming login() returns true on success and false on failure.

medium

A. Login Failed

B. Compilation error

C. Login Successful

D. Runtime exception

Solution

1. Step 1: Understand login method behavior

   login() returns true if credentials are correct, false otherwise.

2. Step 2: Analyze given credentials and output

   Credentials are wrong, so login() returns false, printing "Login Failed".

3. Final Answer:

   Login Failed -> Option A

4. Quick Check:

   False login returns "Login Failed" [OK]

Hint: Check boolean return to decide output [OK]

Common Mistakes:

• Assuming login returns exception on failure
• Confusing true/false return values
• Ignoring ternary operator logic

4. Identify the error in this test class code snippet that uses a page object:

public class LoginTest {
  WebDriver driver;
  LoginPage loginPage;

  @Before
  public void setup() {
    driver = new ChromeDriver();
    loginPage = new LoginPage();
  }

  @Test
  public void testLogin() {
    loginPage.login("user", "pass");
  }
}

medium

A. Test method missing assertion

B. WebDriver is not initialized before use

C. LoginPage constructor is called without passing driver

D. Missing @After method to quit driver

Solution

1. Step 1: Check page object instantiation

   LoginPage requires driver in constructor, but called without arguments here.

2. Step 2: Confirm driver initialization

   Driver is initialized correctly before page object creation, so no issue there.

3. Final Answer:

   LoginPage constructor is called without passing driver -> Option C

4. Quick Check:

   Page object needs driver in constructor [OK]

Hint: Always pass driver when creating page objects [OK]

Common Mistakes:

• Forgetting driver parameter in page object constructor
• Assuming driver auto-initializes in page object
• Ignoring missing assertions (not error here)

5. You want to write a test class that uses two page objects: HomePage and ProfilePage. You want to test the flow: login, navigate to profile, update info, and verify success message. Which approach best follows the test class consuming page objects pattern?

hard

A. Write all element locators and actions inside the test class without page objects

B. Instantiate both page objects with driver, call login on HomePage, then call updateProfile on ProfilePage, finally assert success message from ProfilePage

C. Create one page object combining HomePage and ProfilePage methods, then test all steps there

D. Use driver directly in test class to click and send keys for all steps

Solution

1. Step 1: Understand separation of concerns

   Page objects encapsulate page details; test class uses them to perform test steps and assertions.

2. Step 2: Evaluate options for best practice

   Instantiate both page objects with driver, call login on HomePage, then call updateProfile on ProfilePage, finally assert success message from ProfilePage correctly uses separate page objects and test class calls their methods in sequence.

3. Final Answer:

   Instantiate both page objects with driver, call login on HomePage, then call updateProfile on ProfilePage, finally assert success message from ProfilePage -> Option B

4. Quick Check:

   Test class calls page objects methods in flow [OK]

Hint: Use separate page objects, call their methods in test class [OK]

Common Mistakes:

• Putting all locators and actions in test class
• Combining unrelated page objects into one
• Using driver directly instead of page objects