How to use encode method of org.openqa.selenium.interactions.Interface Encodable class

It doesn't appear in the docs, but if you look at the source code you will see @Deprecated annotation

@Deprecated
public WebDriverWait(WebDriver driver, long timeoutInSeconds) {
    this(driver, Duration.ofSeconds(timeoutInSeconds));
}

In the constructor description you have the solution

@deprecated Instead, use {@link WebDriverWait#WebDriverWait(WebDriver, Duration)}.

Which is the constructor being called from the deprecated one in any case.

new WebDriverWait(driver, Duration.ofSeconds(10));

Write a method like this:

protected boolean isAlertPresent() {
        try {
          driver.switchTo().alert();
          return true;
        } catch (NoAlertPresentException e) {
          return false;
        }
      }

Call the above method to verify whether alert is present or not as below:

if(isAlertPresent()){
            System.out.println(isAlertPresent());
            driver.switchTo().alert().accept();
        }

First of all, I apologise because I had never worked on a grid before. I thought it will be a frame and will be easier to switch and then scroll to the element using JavascriptExecutor. But, alas! That's not the case for a grid.
And, there must be a table when a grid is involved.

Now, this is what has worked for me.

Note: Do not forget to give some sleep time after each scroll.

I have automated one sample grid, and have attached the sample working code below. Hope this helps in figuring out problem:

import java.io.IOException;

import org.openqa.selenium.By;
import org.openqa.selenium.JavascriptExecutor;
import org.openqa.selenium.Keys;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.WebElement;
import org.openqa.selenium.firefox.FirefoxDriver;

public class ScrollGrid{

    public static void main(String[] args) throws IOException, InterruptedException{


        WebDriver driver = new FirefoxDriver();
        driver.get("https://demos.devexpress.com/ASPxGridViewDemos/PagingAndScrolling/VirtualPaging.aspx");
        driver.manage().window().maximize();

        //Clicking on an element inside grid to get it into focus
        driver.findElement(By.xpath("//*[@id='ContentHolder_ASPxGridView1_DXMainTable']//td[.='9/30/1994']")).click();

        WebElement ele=null;
        int flag=0;
        int count=0;

        do{
            try{
                //element to search for while scrolling in grid
                ele = driver.findElement(By.xpath("//*[@id='ContentHolder_ASPxGridView1_DXMainTable']//td[.='3/28/1996']"));
                flag=1;
            } catch(Throwable e){
                //scrolling the grid using the grid's xpath
                driver.findElement(By.xpath("//*[@id='ContentHolder_ASPxGridView1']//div[2]")).sendKeys(Keys.PAGE_DOWN);
                Thread.sleep(3000);
            }
        }while((flag==0) || ((++count)==250));

        if(flag==1){
            System.out.println("Element has been found.!!");
        }else{
            System.out.println("Element has not been found.!!");
        }

        highlightElement(driver, ele); //For highlighting the element
        Thread.sleep(5000L); //to check if the element scrolled to is highlighted.
        driver.close();
    }

    //For highlighting the element to be located after scroll
    public static void highlightElement(WebDriver driver, WebElement ele) {
        try
        {
            for (int i = 0; i < 3; i++) 
            {
                JavascriptExecutor js = (JavascriptExecutor) driver;
                js.executeScript("arguments[0].setAttribute('style', arguments[1]);",ele, "color: red; border: 2px solid red;");
            }
        }
        catch(Throwable t)
        {
            System.err.println("Error came : " +t.getMessage());
        }
    }

}

Note: This works correctly now. It will come out of the loop in case the element is found, or if not found after 250 scrolls. '250' is a relative number. You can change it to the number of scrolls you want to perform on the grid.

Use a try/finally instead of a try/catch.

You don't want to catch the exception and then close the driver, you just want to close the driver at the end of the test, wherever that may be.

And example test method might look like:

public void exampleMethod() {
    WebDriver driver = new FirefoxDriver();

    try {
        //Steps in your test
    }
    finally {
        driver.quit();
    }
}

I've recently looked into BrowserStack with Selenium and the BrowserStack Plugin has made this task much easier.

Features

• Manage your BrowserStack credentials globally or per build job.
• Set up and tear down BrowserStack Local for testing internal, dev or staging environments.
• Embed BrowserStack Automate reports in your Jenkins job results.

Much easier integration all round.

The WebElementWait class as metioned above:

package org.openqa.selenium.support.ui;

import java.util.concurrent.TimeUnit;

import org.openqa.selenium.NotFoundException;
import org.openqa.selenium.WebElement;

public class WebElementWait  extends FluentWait<WebElement>  {
    public final static long DEFAULT_SLEEP_TIMEOUT = 500;

      public WebElementWait(WebElement element, long timeOutInSeconds) {
            this(element, new SystemClock(), Sleeper.SYSTEM_SLEEPER, timeOutInSeconds, DEFAULT_SLEEP_TIMEOUT);
      }

      public WebElementWait(WebElement element, long timeOutInSeconds, long sleepInMillis) {
            this(element, new SystemClock(), Sleeper.SYSTEM_SLEEPER, timeOutInSeconds, sleepInMillis);
      }

      protected WebElementWait(WebElement element, Clock clock, Sleeper sleeper, long timeOutInSeconds,
              long sleepTimeOut) {
            super(element, clock, sleeper);
            withTimeout(timeOutInSeconds, TimeUnit.SECONDS);
            pollingEvery(sleepTimeOut, TimeUnit.MILLISECONDS);
            ignoring(NotFoundException.class);
      }

}

It's the same as WebDriverWait, except that the WebDriver argument is replaced with WebElement.

Then, the isValid method:

//import com.google.common.base.Function;
    //import org.openqa.selenium.TimeoutException;

public boolean isValid(WebElement e) {
    try {
        WebElementWait wait = new WebElementWait(e, 1);
        //@SuppressWarnings("unused")
        //WebElement icon = 
        wait.until(new Function<WebElement, WebElement>() {
                    public WebElement apply(WebElement d) {
                        return d.findElement(By
                                .xpath("./following-sibling::div[class='invalid-icon']"));
                    }
                });
        return false;
    } catch (TimeoutException exception) {
        return true;
    }
}

You can enable JavaScript by doing either

• new HtmlUnitDriver(true);
• driver.setJavascriptEnabled(true);

What you need to do is to wait until the JavaScript is executed after get(url).

You can use Thread.sleep() method for adding some delay.

HtmlUnitDriver driver = new HtmlUnitDriver(BrowserVersion.FIREFOX_3_6);
driver.setJavascriptEnabled(true);
driver.get(url);

Thread.sleep(100);

runTest();

Update

As @Corey indicated in the comments, it could be nicer to use Explicit and Implicit Waits instead of Thread.sleep(). As I don't use them these days, I cannot confirm, though. It would be great if someone test them and update this answer.

If quit() has been called, driver.toString() returns null:

>>> FirefoxDriver: firefox on XP (null))

Otherwise, it returns a hashcode of the object:

>>> FirefoxDriver: firefox on XP (9f897f52-3a13-40d4-800b-7dec26a0c84d)

so you could check for null when assigning a boolean:

boolean hasQuit = driver.toString().contains("(null)");

I feel like your misunderstanding the purposes of WebDriver, Grid and a multi-threaded environment.

Selenium WebDriver is just a test framework that kicks off tests onto a browser. It uses drivers such as geckodriver, and chromedriver to open (and close) browser instances and then hits those instances with actions.

Selenium Grid is a stand-alone server that will run your WebDriver tests remotely on a node and reports back. So if you wanted to use another machines resources to run your test-suite you would be able to do so. It also allows you to combine multiple machines resources by assigning each a node and Selenium Grid will distribute your tests evenly.

As far as your questions about multi-threading,

Is it recommended to use Grid over Selenium WebDriver in a multithreaded environment?

Grid is just a remote-runner of WebDriver. WebDriver is the test-framework. I assume your goal is to reduce your test-suite's run-time by running tests in parallel? Parallel testing can be done on your local machine using WebDriver or can be configured on a Selenium Grid. In my experience, I have gotten more lucky on my local machine than on Grid but both essentially face the same problem. The main danger for parallel testing using WebDriver is thread-safety. JUnit 4.7 onwards and Test-NG RELEASE allow for parallel testing. I highly suggest using Test-NG instead of JUnit for this purpose.

To prevent concurrency issues, your main goal will be to make all your shared resources isolated within each thread. A secondary goal is to limit the scope of all variables to its method. This can be done using a static instance of ThreadLocal It is also really useful to force the initializing of driver instances to be frozen in synchronized methods.

Creating Resources

public class DriverFactory {

    private static String grid = "http://localhost:4444/wd/hub";
    public static ThreadLocal<WebDriver> drivers = new ThreadLocal<WebDriver>();

    public static synchronized void newDriver() {
        ChromeOptions options = new ChromeOptions(); // Assuming Chrome use
            options.addArguments("--start-maximized");

        // USE THIS FOR LOCAL
        // tlDriver.set(new ChromeDriver(options));

        // USE THIS FOR GRID
        try {
            drivers.set(new RemoteWebDriver(new URL(grid),options));
        } catch (MalformedURLException e) {
            e.printStackTrace();
        }
    }

    public static synchronized WebDriver getDriver() {
        return drivers.get();
    }
}

Test Class

public class GoogleTest {
    @BeforeMethod
    public void setup() {
         DriverFactory.newDriver();
    }

    @Test
    public void test1() {
        WebDriver driver = DriverFactory.getDriver();
        driver.navigate().to("https:\\www.google.com");
        Assert.assertEquals(driver.getTitle(), "Google");
    }

    @Test
    public void test2() {
        WebDriver driver = DriverFactory.getDriver();
        driver.navigate().to("https:\\www.google.com");
        Assert.assertEquals(driver.getTitle(), "Google");
    }


    @AfterMethod
    public void tearDown() {
        WebDriver driver = DriverFactory.getDriver();
        driver.quit();
    }
}

TestNG.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE suite SYSTEM "http://testng.org/testng-1.0.dtd">
<!-- thread-count should be = to maxSessions on your Grid -->
<suite name="Whatever" parallel="methods" thread-count="5">
  <test name="Sample">
    <classes>
      <class name="GoogleTest"/>
    </classes>
  </test>
</suite>

Source: Making your Tests Thread-Safe, Full Guide
Versions Used: TestNG 6.14.3, Selenium 3.11, Selenium Grid 3.14.3

Also, would Selenium Grid take responsibility of cleaning any stale browser instances in its nodes (out of the box)?

Selenium Grid has timeout and a browserTimeout features to free up nodes and close browser instances. Although in my experience I would implore you to control any expected timeouts in your test-cases and have WebDriver close the browser instance, not Selenium Grid. You really want to prevent this from happening and eliminate all causes of un-expected hanging. Test-suites are designed to be quick feedback and are only useful if failures are indicative of an actual failure, not just a dirty test-suite. Also stale nodes/browsers can force you to have to constantly reset your grid + nodes which is a major detriment.