How to use setHttpProxy method of org.openqa.selenium.Proxy class

Use inheritance.

public class TestBase {

    protected WebDriver driver;

    @BeforeClass
    public void setUp(){
        System.out.println("I am in setUp method.");

        //WebDriver instantiation etc.
        System.setProperty("webdriver.chrome.driver", "/path/to/chromedriver");
        ChromeOptions options = new ChromeOptions();
        options.addArguments("--start-maximized", "--disable-cache");
        driver = new ChromeDriver(options);
        driver.manage().timeouts().implicitlyWait(10, TimeUnit.SECONDS);
    }

    @AfterClass
    public void tearDown(){
        System.out.println("I am in tearDown method.");

        //You can clean up after tests.
        driver.close();
    }
}

And then inheritance can be used. Pay attention to the extends keyword:

public class ParticularTest extends TestBase {

   @Test
   public void testMethod() {
       System.out.println("I am in testMethod.");

       //Your driver from TestBase is accessible here.
       //Your assertions come here.
   }
}

Later on you can just execute ParticularTest.java. Output:

I am in setUp method.
I am in testMethod.
I am in tearDown method.

Take a look at the section about filling in forms using webdriver in the selenium documentation and the javadoc for the Select class.

To select an option based on the label:

Select select = new Select(driver.findElement(By.xpath("//path_to_drop_down")));
select.deselectAll();
select.selectByVisibleText("Value1");

To get the first selected value:

WebElement option = select.getFirstSelectedOption()

Your stopwatch function should work. In addition, for Selenium to capture the load time at reasonable precision, reduce the amount of wait time between commands. I, typically, use the following logic -

StopWatch s = new StopWatch();
s.start();
while (selenium.isElementPresent("element_locator")) {
   selenium.setSpeed("10");
   Thread.sleep(10);
}
s.stop();
System.out.println("elapsed time in milliseconds: " + s.getElapsedTime());

Here is some more information on the StopWatch class.

The problem was with my IE settings. The problem was resolved when the security settings in IE was changed to "Enable Protected Mode" for "Internet", "Local Intranet", "Trusted Sites" and "Restricted Sites". You can change it by going to Internet Options security tab and enable check box "Enable Protected Mode" for all the zones. I was able to get these information from the link http://jimevansmusic.blogspot.in/2012/08/youre-doing-it-wrong-protected-mode-and.html

You can create a listener implementing IMethodInterceptor interface. Which will give you an ability to access groups list from your @Test and manage your "tests to execute list" as you need. At same time ITestContext parameter allows you to access the data from testNg xml. So, you can set groups to run in default testNg manner (suite xml file); but run them depending on algorithm you implement. Something like:

import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

import org.testng.IMethodInstance;
import org.testng.IMethodInterceptor;
import org.testng.ITestContext;
import org.testng.annotations.Test;

public class Interceptor implements IMethodInterceptor
{

    @Override
    public List<IMethodInstance> intercept(List<IMethodInstance> methods, ITestContext context)
    {
        int methCount = methods.size();
        List<IMethodInstance> result = new ArrayList<IMethodInstance>();

        for (int i = 0; i < methCount; i++)
        {
            IMethodInstance instns = methods.get(i);
            List<String> grps = Arrays.asList(instns.getMethod().getConstructorOrMethod().getMethod().getAnnotation(Test.class).groups());
//get these groups from testng.xml via context method parameter                         
            if (grps.contains("A") && grps.contains("B"))
            {
                result.add(instns);
            }                       
        }                       
        return result;
    }
}

The proper way is to wait explicitly for the product to be added to the cart. Something changes on the page after the operation finishes, right? So wait for that change to occur! I don't know your webpage, obviously, but something along the lines:

// earlier
import static org.openqa.selenium.support.ui.ExpectedConditions.*;

// also earlier, if you want, but you can move it to the loop
WebDriverWait wait = new WebDriverWait(driver, 10);

Iterator<WebElement> button = T2.iterator();
while(button.hasNext()) {
    // find the current number of products in the cart
    String numberOfProductsInCart = driver.findElement(By.id("cartItems")).getText();
    button.next().click();
    // wait for the number of items in cart to change
    wait.until(not(textToBePresentInElement(By.id("cartItems"), numberOfProductsInCart)));
}

I found a workaround about this. My problem was:

1. Selenium inputted 'Mandaluyong' to an auto-suggest location field
2. The auto-suggest field appears together with the matched option
3. Then selenium left the auto-suggest drop-down open not selecting the matched option.

What I did was:

        driver.findElement(By.name("fromLocation")).sendKeys("Mandaluyong");
        driver.findElement(By.name("fromLocation")).sendKeys(Keys.TAB);

This is because on a manual test, when I try to press TAB key, two things were done by the system:

1. Picks the matched option from the auto-suggest drop-down
2. Closes the auto-suggest drop-down

Use the reflected method to get the group of the test as below :

@BeforeMethod
public void befMet(Method m){
        Test t = m.getAnnotation(Test.class);
        System.out.println(t.groups()[0]);//or however you want to use it.
}

I also got the same exception:

I tried the following steps:

1. In Eclipse> Project > Clean. (The Exception remained)

2. I ran another project(The testng.xml ran successfully)

After running another project, I ran the project in which I was getting the Exception, and fortunately it worked for me, with no errors.