Redeclaration of parameters

Question

While looking through the Selenium source code I noticed the following in the PageFactory:

public static <T> T initElements(WebDriver driver, Class<T> pageClassToProxy) {
  T page = instantiatePage(driver, pageClassToProxy);
  initElements(driver, page);
  return page;
}

public static void initElements(WebDriver driver, Object page) {
  final WebDriver driverRef = driver;
  initElements(new DefaultElementLocatorFactory(driverRef), page);
}

What is the benefit of having the following line?

final WebDriver driverRef = driver;

Wouldn't it have made sense to just make the parameter final, and then passing that along to the next method without declaring the new reference?

Answer 1

Well, the answer is that setting final on a variable and only use it as an argument to a function is completely useless. In the DefaultElementLocatorFactory constructor, the variable related to the input argument can be freely reassigned, since it is a copy of the original reference.

P.S. ... unless of course, as suggested by the OP, the input argument is instead declared final.

Answer 2

The best thing I can come up with (under the assumption that the selene devs have more than a basic understanding of how java works - which I think is given):

Presumably before there was a DefaultElementLocatorFactory class, the method used an anonymous inner function and when the code was refactored some parts were just overlooked.