Test Automation in Selenium Using Page Object Model and Page Factory

View all articles

Writing automated tests is more than just a luxury for any agile software development team. It is a need, and is an essential tool to find bugs quickly during early phases of software development cycles. When there is a new feature that is still in development phase, developers can run automated tests and see how other parts of the system are affected by those changes.

Through test automation, it is possible to lower the cost of bug fixing and bring overall improvement to quality assurance (QA) process. With proper tests, developers get a chance at finding and resolving bugs even before it gets to QA. Test automation further helps us to automate test cases and features that are constantly regressing. This way QAs have more time in testing other parts of the application. Moreover, this helps in ensuring quality of the product in production releases. As a result, we get products that are effectively more stable, and a QA process that is more efficient.

Selenium simplifies test automation for web applications

Selenium simplifies test automation for web applications

Although writing automated tests may seem like an easy task for developers and engineers, there is still the possibility of ending up with poorly implemented tests, and the high cost of code maintenance in any agile process. Trying to constantly deliver changes or features in any agile development project can prove to be costly when tests are involved. Changing one element on a web page that 20 tests rely on will require one to go through these 20 test routines and update each one to adapt to this newly introduced change. Not only can this be really time consuming, but a serious de-motivating factor when it comes to implementing automated tests early on.

But, what if we could make the change in one place only, and have every relevant test routine use it? In this article, we will take a look at automated tests in Selenium, and how we can use Page Object models to write maintainable and reusable test routines.

Page Object Model in Selenium

Page Object model is an object design pattern in Selenium, where web pages are represented as classes, and the various elements on the page are defined as variables on the class. All possible user interactions can then be implemented as methods on the class:

clickLoginButton();
setCredentials(user_name,user_password);

Since well-named methods in classes are easy to read, this works as an elegant way to implement test routines that are both readable and easier to maintain or update in the future. For example:

In order to support Page Object model, we use Page Factory. Page Factory is an extension to Page Object and can be used in various ways. In this case we will use Page Factory to initialize web elements that are defined in web page classes or Page Objects.

Web page classes or Page Objects containing web elements need to be initialized using Page Factory before the web element variables can be used. This can be done simply through the use of initElements function on PageFactory:

LoginPage page = new LoginPage(driver);
PageFactory.initElements(driver, page);

Or, even simpler:

LoginPage page = PageFactory.intElements(driver,LoginPage.class)

Or, inside the web page class constructor:

public LoginPage(WebDriver driver) {           
         this.driver = driver; 
         PageFactory.initElements(driver, this);
}

Page Factory will initialize every WebElement variable with a reference to a corresponding element on the actual web page based on configured “locators”. This is done through the use of @FindBy annotations. With this annotation, we can define a strategy for looking up the element, along with the necessary information for identifying it:

@FindBy(how=How.NAME, using="username")
private WebElement user_name;

Every time a method is called on this WebElement variable, the driver will first find it on the current page and then simulate the interaction. In case we are working with a simple page, we know that we will find the element on the page every time we look for it, and we also know that we will eventually navigate away from this page and not return to it, we can cache the looked up field by using another simple annotation:

@FindBy(how=How.NAME, using="username")
@CacheLookup
private WebElement user_name;

This entire definition of the WebElement variable can be replaced with its much more concise form:

@FindBy(name="username")
private WebElement user_name;

The @FindBy annotation supports a handful of other strategies that make things a bit easier:

id, name, className, css, tagName, linkText, partialLinkText, xpath
@FindBy(id="username")
private WebElement user_name;


@FindBy(name="passsword")
private WebElement user_password;


@FindBy(className="h3")
 private WebElement label;


@FindBy(css=”#content”)
private WebElement text;

Once initialized, these WebElement variables can then be used to interact with the corresponding elements on the page. The following code will, for example:

user_password.sendKeys(password);

… send the given sequence of keystrokes to the password field on the page, and it is equivalent to:

driver.findElement(By.name(“user_password”)).sendKeys(password);

Moving on, you will often come across situations where you need to find a list of elements on a page, and that is when @FindBys comes in handy:

@FindBys(@FindBy(css=”div[class=’yt-lockup-tile yt-lockup-video’]”)))
private List<WebElement> videoElements;

The above code will find all the div elements having two class names “yt-lockup-tile” and “yt-lockup-video”. We can simplify this even more by replacing it with the following:

@FindBy(how=How.CSS,using="div[class=’yt-lockup-tile yt-lockup-video’]")
private List<WebElement> videoElements;

Additionally, you can use @FindAll with multiple @FindBy annotations to look for elements that match any of the given locators:

@FindAll({@FindBy(how=How.ID, using=”username”),
	@FindBy(className=”username-field”)})
private WebElement user_name;

Now that we can represent web pages as Java classes and use Page Factory to initialize WebElement variables easily, it is time we see how we can write simple Selenium tests using PO and PF patterns.

Simple Test Automation Project in Java

For our simple project let’s automate developer sign up for Toptal. To do that, we need to automate the following steps:

  • Visit www.toptal.com

  • Click on the “Apply As A Developer” button

  • On Portal Page first check if it’s opened

  • Click on the “Join Toptal” button

  • Fill out the form

  • Submit the form by clicking on “Join Toptal” button

Setting Up a Project

  • Download and install Java JDK

  • Download and install InteliJ Idea

  • Create a new Maven project

  • Link “Project SDK” to your JDK, e.g.: on Windows “C:\Program Files\Java\jdkxxx”

  • Setup groupId and artifactId:

<groupId>SeleniumTEST</groupId>
<artifactId>Test</artifactId>
  • Add dependencies Selenium and JUnit Maven in your project POM file
   <dependencies>
        <!-- JUnit -->         
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>${junit.version}</version>
            <scope>test</scope>
        </dependency>

        <!-- Selenium -->

        <dependency>
            <groupId>org.seleniumhq.selenium</groupId>
            <artifactId>selenium-firefox-driver</artifactId>
            <version>${selenium.version}</version>
        </dependency>

        <dependency>
            <groupId>org.seleniumhq.selenium</groupId>
            <artifactId>selenium-support</artifactId>
            <version>${selenium.version}</version>
        </dependency>

        <dependency>
            <groupId>org.seleniumhq.selenium</groupId>
            <artifactId>selenium-java</artifactId>
            <version>${selenium.version}</version>
        </dependency>

    </dependencies>

Replace Selenium version and JUnit Version with latest version numbers that can be found by searching for JUnit Maven on Google and on Selenium site.

At this point, if auto build is enabled, dependencies should start downloading automatically. If not, just activate Plugins > install > install:install under the Maven Projects panel on the right side of your IntelliJ Idea IDE.

Once the project has been bootstrapped, we can start creating our test package under “src/test/java”. Name the package “com.toptal”, and create two more packages under it: “com.toptal.webpages” and “com.toptal.tests”.

We will keep our Page Object/Page Factory classes under “com.toptal.webpages” and the test routines under “com.toptal.tests”.

Now, we can start creating our Page Object classes.

HomePage Page Object

The very first one we need to implement is for Toptal’s homepage (www.toptal.com). Create a class under “com.toptal.webpages” and name it “HomePage”.

package com.toptal.webpages;

import org.openqa.selenium.WebDriver;
import org.openqa.selenium.WebElement;
import org.openqa.selenium.support.FindBy;
import org.openqa.selenium.support.How;
import org.openqa.selenium.support.PageFactory;

public class HomePage {
   private WebDriver driver;

   //Page URL
   private static String PAGE_URL="https://www.toptal.com";

   //Locators

   //Apply as Developer Button
   @FindBy(how = How.LINK_TEXT, using = "APPLY AS A DEVELOPER")
   private WebElement developerApplyButton;

   //Constructor
   public HomePage(WebDriver driver){
       this.driver=driver;
       driver.get(PAGE_URL);
       //Initialise Elements
       PageFactory.initElements(driver, this);
   }

   public void clickOnDeveloperApplyButton(){

       developerApplyButton.click();

   }
}

Determining Element Locators

On Toptal’s homepage we are interested about one element in particular, and that is the “Apply as a Developer” button. We can find this element by matching the text, which is what we are doing above. While modeling web pages as Page Object classes, finding and identifying elements can often become a chore. With Google Chrome or Firefox’s debugging tools, this can be made easier. By right clicking on any element on a page, you can activate the “Inspect Element” option from the context menu to find out detailed information about the element.

One common (and my preferred) way is to find elements using Firefox’s FireBug extension, in combination with Firefox web driver in Selenium. After installing and enabling FireBug extension, you can right click on the page and select “Inspect element with FireBug” to open FireBug. From the HTML tab of FireBug, you can copy the XPath, CSS Path, Tag name or “Id” (if available) of any element on the page.

By copying the XPath of the element in the screenshot above, we can create a WebElement field for it in our Page Object as follows:

@FindBy(xpath = "/html/body/div[1]/div/div/header/div/h1")
WebElement heading;

Or to keep things simple, we can use the tag name “h1” here, as long as it uniquely identifies the element we are interested in:

@FindBy(tagName = "h1")
WebElement heading;

DeveloperPortalPage Page Object

Next, we need a Page Object that represents the developer portal page, one that we can reach by clicking on the “Apply As A Developer” button.

On this page, we have two elements of interest. To determine if the page has loaded, we want to verify the existence of the heading. And we also want a WebElement field for the “Join Toptal” button.

package com.toptal.webpages;

import org.openqa.selenium.WebDriver;
import org.openqa.selenium.WebElement;
import org.openqa.selenium.support.FindBy;
import org.openqa.selenium.support.PageFactory;

public class DeveloperPortalPage {
   private WebDriver driver;

   @FindBy(xpath = "/html/body/div[1]/div/div/header/div/h1")
   private WebElement heading;

   @FindBy(linkText = "JOIN TOPTAL")
   private WebElement joinToptalButton;

   //Constructor
   public DeveloperPortalPage (WebDriver driver){
       this.driver=driver;

       //Initialise Elements
       PageFactory.initElements(driver, this);
   }

   //We will use this boolean for assertion. To check if page is opened
   public boolean isPageOpened(){
       return heading.getText().toString().contains("Developer portal");
   }

   public void clikOnJoin(){
       joinToptalButton.click();
   }
}

DeveloperApplyPage Page Object

And finally, for our third and last page object for this project, we define one that represents the page containing developer application form. Since we have to deal with a number of form fields here, we define one WebElement variable for every form field. We find each field by their “id” and we define special setter methods for every field that simulate keystrokes for the corresponding fields.

package com.toptal.webpages;

import org.openqa.selenium.WebDriver;
import org.openqa.selenium.WebElement;
import org.openqa.selenium.support.FindBy;
import org.openqa.selenium.support.PageFactory;

public class DeveloperApplyPage {
   private WebDriver driver;

   @FindBy(tagName = "h1")
   WebElement heading;

   @FindBy(id="developer_email")
   WebElement developer_email;

   @FindBy(id = "developer_password")
   WebElement developer_password;

   @FindBy(id = "developer_password_confirmation")
   WebElement developer_password_confirmation;

   @FindBy(id = "developer_full_name")
   WebElement developer_full_name;

   @FindBy(id = "developer_skype")
   WebElement developer_skype;

   @FindBy(id ="save_new_developer")
   WebElement join_toptal_button;


   //Constructor
   public DeveloperApplyPage(WebDriver driver){
       this.driver=driver;

       //Initialise Elements
       PageFactory.initElements(driver, this);
   }

   public void setDeveloper_email(String email){
       developer_email.clear();
       developer_email.sendKeys(email);
   }

   public void setDeveloper_password(String password){
       developer_password.clear();
       developer_password.sendKeys(password);
   }

public void  setDeveloper_password_confirmation(String password_confirmation){
       developer_password_confirmation.clear();
       developer_password_confirmation.sendKeys(password_confirmation);
   }

   public void setDeveloper_full_name (String fullname){
       developer_full_name.clear();
       developer_full_name.sendKeys(fullname);
   }

   public void setDeveloper_skype (String skype){
       developer_skype.clear();
       developer_skype.sendKeys(skype);
   }

   public void clickOnJoin(){
       join_toptal_button.click();
   }
   public boolean isPageOpened(){
       //Assertion
       return heading.getText().toString().contains("Apply to join our network as a developer");
   }
}

Writing a Simple Test

With Page Object classes representing our pages, and user interactions as their methods, we can now write our simple test routine as a series of simple method calls and assertions.

package com.toptal.tests;

import com.toptal.webpages.DeveloperApplyPage;
import com.toptal.webpages.DeveloperPortalPage;
import com.toptal.webpages.HomePage;
import org.junit.After;
import org.junit.Assert;
import org.junit.Before;
import org.junit.Test;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.firefox.FirefoxDriver;

import java.net.URL;
import java.util.concurrent.TimeUnit;

public class ApplyAsDeveloperTest {
   WebDriver driver;

   @Before
   public void setup(){
       //use FF Driver
       driver = new FirefoxDriver();
       driver.manage().timeouts().implicitlyWait(10, TimeUnit.SECONDS);
   }

   @Test
   public void applyAsDeveloper() {
       //Create object of HomePage Class
       HomePage home = new HomePage(driver);
       home.clickOnDeveloperApplyButton();

       //Create object of DeveloperPortalPage
       DeveloperPortalPage devportal= new DeveloperPortalPage(driver);

       //Check if page is opened
       Assert.assertTrue(devportal.isPageOpened());

       //Click on Join Toptal
       devportal.clikOnJoin();

       //Create object of DeveloperApplyPage
       DeveloperApplyPage applyPage =new DeveloperApplyPage(driver);

       //Check if page is opened
       Assert.assertTrue(applyPage.isPageOpened());

       //Fill up data
       applyPage.setDeveloper_email("dejan@toptal.com");
       applyPage.setDeveloper_full_name("Dejan Zivanovic Automated Test");
       applyPage.setDeveloper_password("password123");
       applyPage.setDeveloper_password_confirmation("password123");
       applyPage.setDeveloper_skype("automated_test_skype");

       //Click on join
       //applyPage.clickOnJoin(); 
   }

    @After
    public void close(){
          driver.close();
       }
   }

Running the Test

At this point, your project structure should look like this:

If you want to run the test, select “ApplyAsDeveloperTest” from the tree, right click on it and then select Run ‘ApplyAsDeveloperTest’.

Once the test has been run, you can see the results in the lower-left corner of your IDE:

Conclusion

Page Object and Page Factory make it easy to model web pages in Selenium and test them automatically and make the life of both developers and QAs much more simpler. When done right, these Page Object classes can be reused across your entire test suite and to give yourself the opportunity to implement automated Selenium tests for your projects early on, without compromising agile development. By abstracting away user interactions in your page object models and keeping your test routines light and simple, you can adapt your test suite to changing requirements with little effort.

I hope I have managed to show you how to write nice and clean test code that is easy to maintain. I will end the article with my favorite QA quote:

Think twice, code once!

About the author

Dejan Zivanovic, Serbia
member since May 25, 2014
Dejan is a senior test automation expert with significant experience in web and mobile testing. He has also worked extensively on Android app development, providing him with a strong combination of development and QA skills, and has worked as a QA Lead for a Toptal client. [click to continue...]
Hiring? Meet the Top 10 Freelance Selenium Developers for Hire in September 2016

Comments

Uros Gavric
Excellent article about POM. Thank you!
Dejan Zivanovic
Thanks
Melissa Pontes
Really nice article.
Igor Khrol
https://github.com/yandex-qatools/htmlelements There is a nice library which greatly extends described approach.
Dejan Zivanovic
Thanks
Dejan Zivanovic
Thank you
muhin
Thanks for the nice article. But one point if multiple @Test present than I have to again create the same page object? like DeveloperPortalPage devportal= new DeveloperPortalPage(driver)
Radek
Good article. I'm just putting your advice into practice :) Thanks
Bruno Santos
Great article and good example on Selenium and PageObjects infrastructure. The test though, is in my opinion, a bad test example: 1. Test method is too long 2. More than one single feature is being tested in the same method This is a normal issue when TDD/BDD is not in place. I would recommend writing your requirements in Gherkin first. If you are writing Acceptance Tests (which is what Selenium tests are supposed to do), then use a Gherkin based framework such as Cucumber, JBehave or COLA Tests. If you are just writing normal tests, Gherkin based frameworks are still a good option, but it might be simpler to just use a normal JUnit test with some simple comments to identify the Given, When, Then structure. In time this becomes very simple to use and follow. Here is an example of an Acceptance Test using COLA Tests: https://github.com/bmsantos/cola-tests/wiki/Tutorial-%28Java-&-Selenium%29 And here is an example of a simple unit tests still following the Given, When, Then structure: https://github.com/bmsantos/cola-tests/blob/master/cola-tests/src/test/java/com/github/bmsantos/core/cola/filters/FilterProcessorTest.java Disclaimer: I'am the developer of COLA Tests and I've provided such examples without trying to be biased about it. I'm really just trying to show good practices. It's important to get tests right, not only because they test a given feature, but also because they are the entry point for any feature developer to understand what a given feature is trying to do... a huge part of the so called "living documentation".
Nikolay Advolodkin
Sweet article, I learned a good bit from it!
Nikolay Advolodkin
Dejan, what do you think is the advantage of using the PageFactory with InitElements over something like: By button = Driver.FindElement(By.Id("pooper")); button.Click(); adn then performing actions without the page factory?
Dejan Zivanovic
Hi Yes
Dejan Zivanovic
maybe :)
Dejan Zivanovic
Yes Cucumber is great, I use it, and it's best practice. My topic was PO and PF. You can see nice article in here https://jamesheppinstall.wordpress.com/2012/09/24/behavioural-testing-in-net-with-specflow-and-selenium-part-1/ for .NET, Gerhin....
Dejan Zivanovic
Use it !
Dejan Zivanovic
Changing one element on a web page that 20 tests rely on will require one to go through these 20 test routines and update each one to adapt to this newly introduced change.
Sinaru
Nice article on POM.
Dejan Zivanovic
thanks
Prasanna K C Dommalapati
This article is really helped me in Creating and maintaining POM. Thanq very much.
Dejan Zivanovic
Thanks :)
Dejan Zivanovic
yes it's needs to be private :)
Dejan Zivanovic
there is no difference, but if you change you find to css you can easy change with How....
Bruno Santos
Dejan, Not sure what makes you say that, but Gherkin feature/stories must be written before anything else as their real purpose is to provide a specification to serve as baseline or requirements between business needs and wants. I would recommend reading "Specification by example" by Gojko Adzic. https://www.manning.com/books/specification-by-example
Dejan Zivanovic
No problem :)
sona
When I trying to run a testsuite some testcases are failed they are unstable.Is the POM and page factory solution for that
Dejan Zivanovic
@FindBy(xpath=".//*[@id='profile_Profile']/table/tbody/tr[1]/td[1]") WebElement homePageUserName; or @FindBys({ @FindBy(id = "profile_Profile"), }) public List<WebElement> allElementsInList; or something like: @FindBys({ @FindBy(xpath=".//*[@id='profile_Profile']/table/tbody/tr[1]"), }) public List<WebElement> allElementsInList;
Dejan Zivanovic
@FindBys({ @FindBy(id = "profile_Profile"), }) public List<webelement> allElementsInList;
Dejan Zivanovic
use implicit wait for element
Andrejs88
Hi Dejan. I appreciated the the post and information sharing, and I certainly understand that it's meant as a basic example, but even a simple example should promote best practices where appropriate. This post, however, demonstrates several important issues: - "Flaky test": Using text to click on element (buttons) + "isPageOpened" method: text changes often (and it did) so it's better to use other ways - "Not DRY": Not abstracting setup and teardown into @beforeclass and @afterclass to run with every test - "Unclear diagnostics": If the test fails, you just get "java.lang.AssertionError" and you have to go through the stack to understand what went wrong. Using an "asssertTrue" with a different signature --> (String message, boolean condition) and adding a custom message makes debugging much easier. Of course there are many many other things that are outside of the scope for an "intro" article, but the above require little extra code but would avoid several anti-patterns. Regards
comments powered by Disqus
Subscribe
The #1 Blog for Engineers
Get the latest content first.
No spam. Just great engineering and design posts.
The #1 Blog for Engineers
Get the latest content first.
Thank you for subscribing!
You can edit your subscription preferences here.
Trending articles
Relevant technologies
About the author
Dejan Zivanovic
Automation Testing Developer
Dejan is a senior test automation expert with significant experience in web and mobile testing. He has also worked extensively on Android app development, providing him with a strong combination of development and QA skills, and has worked as a QA Lead for a Toptal client.