Inheriting WebDriver Throughout Your Page Object Classes

Inheriting WebDriver Throughout Your Page Object Classes

I’ve seen (and written) several automation projects where each page class requires a constructor that takes a WebDriver object so that the page classes can access the current browser instance. There’s nothing particularly wrong with this, but I do find it a bit annoying to pass around the WebDriver like a hot potato. Instead, you can use inheritance.

My preferred approach is to create a base test class which defines a WebDriver object, instantiates it, and then sets it in a base page. Subsequent page classes then inherit from the base page, thus automatically having access to the driver.

package tests;
import org.junit.AfterClass;
import org.junit.BeforeClass;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.chrome.ChromeDriver;

import pages.Page;

public class BaseTest {

	private static WebDriver webDriver;
	protected static Page basePage;
	
	private static final String APP_URL = "http://store.demoqa.com";

	@BeforeClass
	public static void launchApplication(){
		setChromeDriverProperty();
		webDriver = new ChromeDriver();
		webDriver.get(APP_URL);
		basePage = new Page();
		basePage.setWebDriver(webDriver);
	}

	@AfterClass
	public static void closeBrowser(){
		webDriver.quit();
	}

	private static void setChromeDriverProperty(){
		System.setProperty("webdriver.chrome.driver", "resources/chromedriver");
	}

}

package tests;

import org.junit.AfterClass;

import org.junit.BeforeClass;

import org.openqa.selenium.WebDriver;

import org.openqa.selenium.chrome.ChromeDriver;

import pages.Page;

public class BaseTest {

private static WebDriver webDriver;

protected static Page basePage;

private static final String APP_URL = "http://store.demoqa.com";

@BeforeClass

public static void launchApplication(){

setChromeDriverProperty();

webDriver = new ChromeDriver();

webDriver.get(APP_URL);

basePage = new Page();

basePage.setWebDriver(webDriver);

}

@AfterClass

public static void closeBrowser(){

webDriver.quit();

}

private static void setChromeDriverProperty(){

System.setProperty("webdriver.chrome.driver", "resources/chromedriver");

}

Notice that here in the base test class, in addition to instantiating the WebDriver, we also create a handle to the base page and set the WebDriver in that page. By doing this, no tests need to touch the WebDriver.

Here’s an example of the Page class

package pages;

import org.openqa.selenium.By;
import org.openqa.selenium.Keys;
import org.openqa.selenium.WebDriver;

public class Page {
	
	protected static WebDriver driver;
	
	private static final String SEARCH_FIELD_CLASS = "s";
	private static final String CART_LINK_CLASS = "cart_icon";
	
	public void setWebDriver(WebDriver driver) {
		Page.driver = driver;
	}
	
	public void search(String query) {
		driver.findElement(By.className(SEARCH_FIELD_CLASS)).sendKeys(query + Keys.ENTER);
	}
	
	public CartPage clickCheckoutLink() {
		driver.findElement(By.className(CART_LINK_CLASS)).click();
		return new CartPage();
	}
}

package pages;

import org.openqa.selenium.By;

import org.openqa.selenium.Keys;

import org.openqa.selenium.WebDriver;

public class Page {

protected static WebDriver driver;

private static final String SEARCH_FIELD_CLASS = "s";

private static final String CART_LINK_CLASS = "cart_icon";

public void setWebDriver(WebDriver driver) {

Page.driver = driver;

}

public void search(String query) {

driver.findElement(By.className(SEARCH_FIELD_CLASS)).sendKeys(query + Keys.ENTER);

}

public CartPage clickCheckoutLink() {

driver.findElement(By.className(CART_LINK_CLASS)).click();

return new CartPage();

}

I use the Page class as a base that contains functionality that is available on any page within the application, such as the search and clickCheckoutLink functions. Then any new page object class I create, can simply inherit from this class, thus gaining access to the WebDriver. Notice there’s no need for a constructor that accepts the WebDriver object in this page class.

package pages;

import org.openqa.selenium.By;

public class CartPage extends Page {

	private static final String PRODUCT_TABLE = "//table[@class='checkout_cart']";
	private static final String PRODUCT_TABLE_ROWS = PRODUCT_TABLE + "/tbody/tr[contains(@class, 'product_row')]";
	
	public int getNumberOfProductsInCart() {
		return driver.findElements(By.xpath(PRODUCT_TABLE_ROWS)).size();
	}
}

package pages;

import org.openqa.selenium.By;

public class CartPage extends Page {

private static final String PRODUCT_TABLE = "//table[@class='checkout_cart']";

private static final String PRODUCT_TABLE_ROWS = PRODUCT_TABLE + "/tbody/tr[contains(@class, 'product_row')]";

public int getNumberOfProductsInCart() {

return driver.findElements(By.xpath(PRODUCT_TABLE_ROWS)).size();

}

Here’s an example of a simple test just to make sure everything works. Test classes that extend from BaseTest will not need to instantiate a page class to get started, as they inherit the basePage instance from BaseTest.

package tests;

import org.junit.Test;

import org.junit.Assert;
import pages.CartPage;

public class CartTests extends BaseTest {
	
	@Test
	public void testEmptyCart() {
		CartPage cart = basePage.clickCheckoutLink();
		Assert.assertEquals("Cart should be empty", 0, cart.getNumberOfProductsInCart());
	}
}

package tests;

import org.junit.Test;

import org.junit.Assert;

import pages.CartPage;

public class CartTests extends BaseTest {

@Test

public void testEmptyCart() {

CartPage cart = basePage.clickCheckoutLink();

Assert.assertEquals("Cart should be empty", 0, cart.getNumberOfProductsInCart());

}

NON-STATIC WEBDRIVER

I received a question on Twitter asking is there a way to do this without making the WebDriver static.

@techgirl1908 Hi, how do you make webdriver as non static and make it available throughout the project. Can you point me to framework or project where webdriver is made non- static.

— @sreeaga (@sreeagasth) December 11, 2017

If using Junit which comes with the Selenium dependencies, their Before and After methods are static and therefore force some things upon us. We can still get around making the WebDriver static but it takes a bit of wizardry. You can essentially make a static instance to the BaseTest class itself, and create a non-default constructor that does what your static setup method would have.

package tests;
import org.junit.AfterClass;
import org.junit.BeforeClass;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.chrome.ChromeDriver;

import pages.Page;

public class BaseTest {

	private WebDriver webDriver;
	private static BaseTest baseTest;
	protected static Page basePage;
	private final String APP_URL = "http://store.demoqa.com";
	
	public BaseTest() { 
		this(false); 
	}
	
	public BaseTest(boolean launch) {
		if(launch) {
			setChromeDriverProperty();
			webDriver = new ChromeDriver();
			webDriver.get(APP_URL);
			basePage = new Page();
			basePage.setWebDriver(webDriver);
		}
	}

	@BeforeClass
	public static void launchApplication(){
		baseTest = new BaseTest(true);
	}

	@AfterClass
	public static void closeBrowser(){
		baseTest.webDriver.close();
	}

	private static void setChromeDriverProperty(){
		System.setProperty("webdriver.chrome.driver", "resources/chromedriver");
	}

}

package tests;

import org.junit.AfterClass;

import org.junit.BeforeClass;

import org.openqa.selenium.WebDriver;

import org.openqa.selenium.chrome.ChromeDriver;

import pages.Page;

public class BaseTest {

private WebDriver webDriver;

private static BaseTest baseTest;

protected static Page basePage;

private final String APP_URL = "http://store.demoqa.com";

public BaseTest() {

this(false);

}

public BaseTest(boolean launch) {

if(launch) {

setChromeDriverProperty();

webDriver = new ChromeDriver();

webDriver.get(APP_URL);

basePage = new Page();

basePage.setWebDriver(webDriver);

}

@BeforeClass

public static void launchApplication(){

baseTest = new BaseTest(true);

}

@AfterClass

public static void closeBrowser(){

baseTest.webDriver.close();

}

private static void setChromeDriverProperty(){

System.setProperty("webdriver.chrome.driver", "resources/chromedriver");

}

All other classes remain the same. This works, but feels hacky to me, which is why I prefer the first approach. But I understand people’s projects may require different things. Another alternative would be to use TestNG or another assertion tool that does not require static Before and After methods.

December 21, 2017

15 Comments

Timothy Western

This is similar to am approach I’ve used several times. It allows a lot of setup to happen consistently through the parent constructor. And it does so while allowing the possibility of extension not for social cases without to much trouble.

December 23, 2017 at 9:11 am Reply
Samreen Chughtai

How can I implement it in PageFactory. Where to initiate page object elements??

May 28, 2018 at 6:31 am Reply
- Eliezer
  
  Use this in the main Page.
  
  package com.Pages;
  
  import com.Global.Global;
  
  import org.openqa.selenium.WebDriver;
  
  import org.openqa.selenium.support.PageFactory;
  
  public class GlobalPage extends Global {
  
  protected static WebDriver driver;
  
  public void setWebDriver(WebDriver driver) {
  
  GlobalPage.driver = driver;
  
  PageFactory.initElements(driver, this);
  
  }
  
  }
  
  March 5, 2021 at 12:19 pm Reply
Sivasankaramalan

If you want to use (

WebDriverWait wait = new WebDriverWait( driver , 30);) in different class file how we inheriting the WebDriver??

May 17, 2019 at 4:15 pm Reply
Bi Chand

Can u please do similar example with PageFactory?

July 29, 2019 at 8:00 pm Reply
- Eliezer
  
  package com.Pages;
  
  import com.Global.Global;
  
  import org.openqa.selenium.WebDriver;
  
  import org.openqa.selenium.support.PageFactory;
  
  public class GlobalPage extends Global {
  
  protected static WebDriver driver;
  
  public void setWebDriver(WebDriver driver) {
  
  GlobalPage.driver = driver;
  
  PageFactory.initElements(driver, this);
  
  }
  
  }
  
  March 5, 2021 at 11:31 am Reply
Zoé Thivet

Used it in my new project. Thanks for this tip

December 25, 2019 at 8:31 pm Reply
Madhuri R Gaddam

Please can you share how to use this using Testng.

January 7, 2020 at 12:08 pm Reply
- Angie Jones
  
  Check out this chapter of my course. Start the video at 4.26 for where TestNG starts
  
  https://testautomationu.applitools.com/selenium-webdriver-tutorial-java/chapter4.2.html
  
  January 7, 2020 at 2:03 pm Reply
  - Madhuri R Gaddam
    
    Angie , I appreciate your quick response I am able to implement this.
    
    January 8, 2020 at 5:34 am Reply
Ifeoma Emodi

Am not sure if this is the right question but in the BaseTest class above, you did add

protected static Page basePage ;

Do I have to do this for every class, that I will create or not

e.g.

protected static Login loginPage;

protected static Registration registrationPage;

If so the BaseTest class will be clogged up

March 11, 2020 at 9:26 am Reply
- Angie Jones
  
  No, I only do it for Page which is a super class for all other pages.
  
  March 29, 2020 at 9:04 pm Reply
Owyn Dwight

Hey Angie,

Is there a particular reason you don’t use the @FindBy annotation/pagefactory in general, I was always taught to use POM this way but I see you do this using traditional ‘findElement()’. Or maybe I have missed another article :D.

Thank you in advance

September 29, 2020 at 2:22 am Reply
- Angie Jones
  
  Yes, the Selenium project lead, Simon Stewart advises against using it and has said it was a mistake to add it to the project. It’s even been deprecated in some of the languages.
  https://sqa.stackexchange.com/questions/37553/pagefactory-is-deprecated-in-c-net-what-to-use-instead-of-that
  
  October 2, 2020 at 8:48 pm Reply
Rahul

Please send the demo project for same approach which you used.

July 23, 2021 at 7:55 am Reply

Inheriting WebDriver Throughout Your Page Object Classes