JUnit Parallel Testing - selenium

Question

I'm trying to run a piece of code that I found online to run JUnit test in parallel but the only thing I've modified is the URL to hit my local host. Problem is I'm constantly getting the following error and even though I've setup selenium grid many times and know how to set paths etc. I don't know how to fix this one.
org.openqa.selenium.WebDriverException: The path to the driver executable must be set by the webdriver.ie.driver system property; for more information, see http://code.google.com/p/selenium/wiki/InternetExplorerDriver.
here's the code
package AutomationFrameWork;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.TimeUnit;
import org.junit.runners.Parameterized;
import org.junit.runners.model.RunnerScheduler;
public class Parallelized extends Parameterized {
private static class ThreadPoolScheduler implements RunnerScheduler {
private ExecutorService executor;
public ThreadPoolScheduler() {
String threads = System.getProperty("junit.parallel.threads", "16");
int numThreads = Integer.parseInt(threads);
executor = Executors.newFixedThreadPool(numThreads);
}
#Override
public void finished() {
executor.shutdown();
try {
executor.awaitTermination(10, TimeUnit.MINUTES);
} catch (InterruptedException exc) {
throw new RuntimeException(exc);
}
}
#Override
public void schedule(Runnable childStatement) {
executor.submit(childStatement);
}
}
public Parallelized(Class<?> klass) throws Throwable {
super(klass);
setScheduler(new ThreadPoolScheduler());
}
}
package AutomationFrameWork;
import java.io.File;
import java.io.IOException;
import java.net.URL;
import java.util.LinkedList;
import org.apache.commons.io.FileUtils;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.Parameterized;
import org.openqa.selenium.By;
import org.openqa.selenium.OutputType;
import org.openqa.selenium.Platform;
import org.openqa.selenium.TakesScreenshot;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.WebElement;
import org.openqa.selenium.remote.Augmenter;
import org.openqa.selenium.remote.DesiredCapabilities;
import org.openqa.selenium.remote.RemoteWebDriver;
#RunWith(Parallelized.class)
public class JUnitParallel {
private String platform;
private String browserName;
private String browserVersion;
private WebDriver driver;
#Parameterized.Parameters
public static LinkedList<String[]> getEnvironments() throws Exception {
LinkedList<String[]> env = new LinkedList<String[]>();
env.add(new String[]{Platform.WINDOWS.toString(), "chrome", "27"});
env.add(new String[]{Platform.WINDOWS.toString(),"firefox","20"});
env.add(new String[]{Platform.WINDOWS.toString(),"ie","11"});
env.add(new String[]{Platform.WINDOWS.toString(),"safari","5.1.7"});
//add more browsers here
return env;
}
public JUnitParallel(String platform, String browserName, String browserVersion) {
this.platform = platform;
this.browserName = browserName;
this.browserVersion = browserVersion;
}
#Before
public void setUp() throws Exception {
DesiredCapabilities capability = new DesiredCapabilities();
capability.setCapability("platform", platform);
capability.setCapability("browser", browserName);
capability.setCapability("browserVersion", browserVersion);
capability.setCapability("build", "JUnit-Parallel");
capability.setCapability("InternetExplorerDriverServer.IE_ENSURE_CLEAN_SESSION",true);
System.setProperty("webdriver.ie.driver",
"C:\\Users\\path to driver\\IEDriverServer.exe");
driver = new RemoteWebDriver(
new URL("http://localhost:7777".concat("/wd/hub")),
capability
);
}
#Test
public void testSimple() throws Exception {
driver.get("http://www.google.com");
String title = driver.getTitle();
System.out.println("Page title is: " + title);
WebElement element = driver.findElement(By.name("q"));
element.sendKeys("BrowserStack");
element.submit();
driver = new Augmenter().augment(driver);
File srcFile = ((TakesScreenshot) driver).getScreenshotAs(OutputType.FILE);
try {
FileUtils.copyFile(srcFile, new File("Screenshot.png"));
} catch (IOException e) {
e.printStackTrace();
}
}
#After
public void tearDown() throws Exception {
driver.quit();
}
}