WebDriver driver = new FirefoxDriver（）是编译时绑定还是运行时绑定？

Question

It looks like I got a bit confused in my core Java concepts .Please have a look below .

    class A{
       public void func1()
       {
           System.out.println("Hello A");
       }
    }
    class B extends A{
       public void func1(){
           System.out.println("Hello B");
       }
     }
   class C {
        public static void main( String args[]) {

           A myobj = new B();
           myobj.func1();
       }
}

As we know Webdriver is an interface & FirefoxDriver is the implementing class for Webdriver , so based on the above example is it right to assume that the statement : WebDriver driver=new FirefoxDriver() is an example of late binding.

Answer 1

WebDriver driver=new FirefoxDriver() is this compile-time or runtime binding?

That's compile-time binding to the class called FirefoxDriver . It will use whatever FirefoxDriver class is in the classpath. This is just about as compile-time as Java gets, as Java works from the classpath at compile-time and also at runtime.

Here's an example of runtime binding:

String driverName = /*...get the name from somewhere, like a properties file...*/;
WebDriver driver = Class.forName(driverName).newInstance();