Induce WebDriverWait and elementToBeClickable to click on the element.

Try the following options.

WebDriverWait wait = new WebDriverWait(driver, 30);
WebElement selectGender = wait.until(ExpectedConditions.elementToBeClickable(By.id("id_gender1")));
selectGender.click()

OR

WebDriverWait wait = new WebDriverWait(driver, 30);
WebElement selectGender = wait.until(ExpectedConditions.elementToBeClickable(By.xpath("//div[@class='radio-inline']/label[@for='id_gender1']")));
selectGender.click()

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.

In your settings enable "Launch AVD" and enter the name of the Android Virtual Device you created. This will start the emulator (if it's not already started) whenever you start a test.

Update:

You need to set the AVD capability. Simply add this line to your code capabilities.setCapability("avd","AndroidTestDevice");

Unfortunately

this is not possible with native Selenium API.

But using Javascript you can:

You can use some javascript support, using Seleniums' JavascriptExecutor.executeScript functionality.

The necessary js code can be found here and here(as proposed by @Mahsum Akbas)

Now here is the Java/Selenium Code that will return you a string in the form of "css-attribute01:value01; css-attribute02:value02;".

Be aware that this will return ALL css-attributes on the element.

WebElement we = driver.findElement(By.tagName("div"));
JavascriptExecutor executor = (JavascriptExecutor)driver;
String script = "var s = '';" +
                "var o = getComputedStyle(arguments[0]);" +
                "for(var i = 0; i < o.length; i++){" +
                "s+=o[i] + ':' + o.getPropertyValue(o[i])+';';}" + 
                "return s;";

System.out.println(executor.executeScript(script, we));

You can change the script according to your needs. For example you could return a string that ONLY has all the values without the attributes. Feel free to change and experiment.

Update

If you would be interested in only the inline-styles of the element, then you can use "native" Selenium as pointed out by @JeffC in the comments:

driver.findElement(By.tagName("div")).getAttribute("style")

BUT!:

This will give you only the "inline styles" and NOT all the css-styles that are applied to an element. If you run both versions after one another and print the results you will see the immense difference.

Agree with Subir Kumar Sao and Faiz.

element_enter.findElement(By.xpath("//html/body/div[1]/div[3]/div[1]/form/div/div/input")).sendKeys(barcode);

First the update ¹

execute_cdp_cmd(): With the availability of execute_cdp_cmd(cmd, cmd_args) command now you can easily execute google-chrome-devtools commands using Selenium. Using this feature you can modify the navigator.webdriver easily to prevent Selenium from getting detected.

Preventing Detection ²

To prevent Selenium driven WebDriver getting detected a niche approach would include either / all of the below mentioned steps:

• Adding the argument --disable-blink-features=AutomationControlled

  from selenium import webdriver
  
  options = webdriver.ChromeOptions() 
  options.add_argument('--disable-blink-features=AutomationControlled')
  driver = webdriver.Chrome(options=options, executable_path=r'C:\WebDrivers\chromedriver.exe')
  driver.get("https://www.website.com")
  

You can find a relevant detailed discussion in Selenium can't open a second page

• Rotating the user-agent through execute_cdp_cmd() command as follows:

  #Setting up Chrome/83.0.4103.53 as useragent
  driver.execute_cdp_cmd('Network.setUserAgentOverride', {"userAgent": 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/83.0.4103.53 Safari/537.36'})
  

• Change the property value of the navigator for webdriver to undefined

  driver.execute_script("Object.defineProperty(navigator, 'webdriver', {get: () => undefined})")
  

• Exclude the collection of enable-automation switches

  options.add_experimental_option("excludeSwitches", ["enable-automation"])
  

• Turn-off useAutomationExtension

  options.add_experimental_option('useAutomationExtension', False)
  

Sample Code ³

Clubbing up all the steps mentioned above and effective code block will be:

from selenium import webdriver

options = webdriver.ChromeOptions() 
options.add_argument("start-maximized")
options.add_experimental_option("excludeSwitches", ["enable-automation"])
options.add_experimental_option('useAutomationExtension', False)
driver = webdriver.Chrome(options=options, executable_path=r'C:\WebDrivers\chromedriver.exe')
driver.execute_script("Object.defineProperty(navigator, 'webdriver', {get: () => undefined})")
driver.execute_cdp_cmd('Network.setUserAgentOverride', {"userAgent": 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/83.0.4103.53 Safari/537.36'})
print(driver.execute_script("return navigator.userAgent;"))
driver.get('https://www.httpbin.org/headers')

History

As per the W3C Editor's Draft the current implementation strictly mentions:

The webdriver-active flag is set to true when the user agent is under remote control which is initially set to false.

Further,

Navigator includes NavigatorAutomationInformation;

It is to be noted that:

The NavigatorAutomationInformation interface should not be exposed on WorkerNavigator.

The NavigatorAutomationInformation interface is defined as:

interface mixin NavigatorAutomationInformation {
    readonly attribute boolean webdriver;
};

which returns true if webdriver-active flag is set, false otherwise.

Finally, the navigator.webdriver defines a standard way for co-operating user agents to inform the document that it is controlled by WebDriver, so that alternate code paths can be triggered during automation.

Caution: Altering/tweaking the above mentioned parameters may block the navigation and get the WebDriver instance detected.

Update (6-Nov-2019)

As of the current implementation an ideal way to access a web page without getting detected would be to use the ChromeOptions() class to add a couple of arguments to:

• Exclude the collection of enable-automation switches
• Turn-off useAutomationExtension

through an instance of ChromeOptions as follows:

• Java Example:

  System.setProperty("webdriver.chrome.driver", "C:\\Utility\\BrowserDrivers\\chromedriver.exe");
  ChromeOptions options = new ChromeOptions();
  options.setExperimentalOption("excludeSwitches", Collections.singletonList("enable-automation"));
  options.setExperimentalOption("useAutomationExtension", false);
  WebDriver driver =  new ChromeDriver(options);
  driver.get("https://www.google.com/");
  

• Python Example

  from selenium import webdriver
  
  options = webdriver.ChromeOptions()
  options.add_experimental_option("excludeSwitches", ["enable-automation"])
  options.add_experimental_option('useAutomationExtension', False)
  driver = webdriver.Chrome(options=options, executable_path=r'C:\path\to\chromedriver.exe')
  driver.get("https://www.google.com/")
  

• Ruby Example

    options = Selenium::WebDriver::Chrome::Options.new
    options.add_argument("--disable-blink-features=AutomationControlled")
    driver = Selenium::WebDriver.for :chrome, options: options
  

Legends

¹: Applies to Selenium's Python clients only.

²: Applies to Selenium's Python clients only.

³: Applies to Selenium's Python clients only.

The typical solution to this is a try/catch against a wait. E.g. if the next step is to click a button that shows once loading completes:

    WebDriverWait wait = new WebDriverWait(driver, LOADING_TIMEOUT);

    WebElement webElement;
    try {
        webElement = wait.until(elementToBeClickable(By.id(id)));
    } catch (TimeoutException ex) {
        // Close loading window
        return;
    }

    webElement.click();

However, there is a common problem if you are using implicit timeouts in Selenium. This doesn't work too well, particularly if the implicit timeout is longer than the LOADING_TIMEOUT, as this slows down the polling cycle in the wait.until().

In this case, the simplest solution is to temporarily reduce the implicit timeout:

    WebDriverWait wait = new WebDriverWait(driver, LOADING_TIMEOUT);

    WebElement webElement;
    try {
        driver.manage().timeouts().implicitlyWait(1, TimeUnit.SECONDS);
        webElement = wait.until(elementToBeClickable(By.id(id)));
    } catch (TimeoutException ex) {
        // Delay any further interaction until the timeout has been restored
        webElement = null;
    } finally {
        driver.manage().timeouts().implicitlyWait(DEFAULT_TIMEOUT,
                TimeUnit.SECONDS);
    }

    if (webElement != null)
        webElement.click();
    else
        // Close loading window

WebDriver is an interface.

FirefoxDriver is the implementation.

To understand better, please do read docs on Java Interface.

Your locator is correct. Try getAttribute("innerHTML") instead of getText()

driver.findElement(By.xpath("//table[@id='myTable']/tbody/tr/td")).getAttribute("innerHTML");