WebDriver

WebDriver
Uses Selenium’s javascript Selenium-Core. WebDriver does not depend on a javascript core embedded within the browser, therefore it is able to avoid some long-running Selenium limitations.

Sample:
package com.sample.tests;

import java.util.List;

import org.openqa.selenium.By;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.RenderedWebElement;
import org.openqa.selenium.WebElement;
import org.openqa.selenium.firefox.FirefoxDriver;

public class LoginPage {
   public static void main(String[] args) throws Exception {
       // The Firefox driver supports javascript
       WebDriver driver = new FirefoxDriver();

       // Open Loginpage
       driver.get("http://localhost:8220/login.jsp");

       // Enter the query string "Cheese"
       WebElement userId = driver.findElement(By.id("loginName"));
       WebElement password = driver.findElement(By.id("password"));
       WebElement submit = driver.findElement(By.id("submitbtn"));

       loginName.sendKeys("Maddy");
       password.sendKeys("pass");
       submit.click();
             try{
                 if(driver.findElement(By.id("LoggedusrNm"))!=null)
                    Assert.assertEquals("Done");
                }catch(NoSuchElementException e){
                  Assert.fail("No LoggedUser label available");
                     }
    }
}