Properties file for configuration in Selenium Java - Build an Automation Script

Verify login functionality using credentials from properties file

Preconditions (2)

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

Step 2: Read 'username' and 'password' values from config.properties file

Step 3: Enter the username into the username input field with id 'username'

Step 4: Enter the password into the password input field with id 'password'

Step 5: Click the login button with id 'loginBtn'

Step 6: Wait for the page to load and verify the URL is http://example.com/dashboard

✅ Expected Result: User is successfully logged in and redirected to the dashboard page

Automation Requirements - Selenium WebDriver with TestNG

Assertions Needed:

Verify the current URL after login matches http://example.com/dashboard

Best Practices:

Use explicit waits to wait for page load or elements

Load configuration from properties file using java.util.Properties

Use Page Object Model to separate page elements and actions

Close the browser after test execution

Automated Solution

Selenium Java

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 org.testng.Assert;
import org.testng.annotations.AfterClass;
import org.testng.annotations.BeforeClass;
import org.testng.annotations.Test;

import java.io.FileInputStream;
import java.io.IOException;
import java.time.Duration;
import java.util.Properties;

public class LoginTest {
    private WebDriver driver;
    private WebDriverWait wait;
    private Properties config;

    @BeforeClass
    public void setUp() throws IOException {
        // Load properties file
        config = new Properties();
        FileInputStream fis = new FileInputStream("config.properties");
        config.load(fis);
        fis.close();

        // Setup WebDriver
        driver = new ChromeDriver();
        wait = new WebDriverWait(driver, Duration.ofSeconds(10));
    }

    @Test
    public void testLoginWithProperties() {
        driver.get("http://example.com/login");

        // Enter username
        WebElement usernameInput = wait.until(ExpectedConditions.visibilityOfElementLocated(By.id("username")));
        usernameInput.sendKeys(config.getProperty("username"));

        // Enter password
        WebElement passwordInput = driver.findElement(By.id("password"));
        passwordInput.sendKeys(config.getProperty("password"));

        // Click login button
        WebElement loginButton = driver.findElement(By.id("loginBtn"));
        loginButton.click();

        // Wait for URL to change to dashboard
        wait.until(ExpectedConditions.urlToBe("http://example.com/dashboard"));

        // Assert URL
        String currentUrl = driver.getCurrentUrl();
        Assert.assertEquals(currentUrl, "http://example.com/dashboard", "User should be redirected to dashboard after login");
    }

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

This test class uses Selenium WebDriver with TestNG to automate login using credentials from a properties file.

setUp(): Loads the config.properties file using Properties class and initializes the ChromeDriver and explicit wait.

testLoginWithProperties(): Opens the login page, waits for username input to be visible, enters username and password from the properties file, clicks login, waits until the URL changes to the dashboard URL, then asserts the URL is correct.

tearDown(): Closes the browser after the test finishes.

Explicit waits ensure elements are ready before interacting. Using properties file keeps credentials outside the code for easy updates.

Common Mistakes - 4 Pitfalls

Hardcoding username and password in the test code

Using Thread.sleep() instead of explicit waits

Not closing the FileInputStream after loading properties

Using brittle XPath selectors instead of stable IDs

Bonus Challenge

Now add data-driven testing with 3 different username and password combinations from the properties file

Show Hint