Source:How to use java.net.URLConnection to fire and handle HTTP requests
File pathToBinary = new File("C:\\Program Files\\Mozilla Firefox\\firefox.exe");
FirefoxBinary ffBinary = new FirefoxBinary(pathToBinary);
FirefoxProfile firefoxProfile = new FirefoxProfile();
System.setProperty("webdriver.gecko.driver","C:\\Users\\Downloads\\selenium-java-3.0.1\\geckodriver.exe");
WebDriver driver = new FirefoxDriver(ffBinary,firefoxProfile);