How to open specific browser using selenium webdriver

Question

I am using lang :java framework: testNG

my system has 3-4 versions of Mozilla installed, how can i open instance of specific version of Mozilla. Suppose i have 3.5, 3.6,

Answer 1

System.setProperty("webdriver.chrome.driver", "./chromedriver.exe");  //for chrome
driver = new ChromeDriver();
driver.manage().window().maximize();
driver.get("WebsiteURL");


System.setProperty("webdriver.gecko.driver", "./geckodriver.exe");  //for firefox
driver=new FirefoxDriver();
driver.manage().window().maximize();
driver.get("WebsiteURL");