对 By/BySelector 使用 Optional 的空检查

Question

I want to re-write my null checking code, and use Optional instead.

public BySelector select(BySelector bySelector, Boolean value) {
  return (bySelector == null) ? By.checkable(value) : bySelector.checkable(value);
}

The above is my original code. I have no idea how to replace to Optional. I've tried the following but it is not working. Please advise. Thank you.

public BySelector select(BySelector bySelector, Boolean value) {
  return Optional.ofNullable(bySelector.checkable(value).orElse(By.checkable(value);
}

Answer 1

There is no need to use Optional in your case as it is less clear than your simple null check, but this is how I would do :

Optional.ofNullable(bySelector)
        .map(x -> By.checkable(value))
        .orElse(BySelector.checkable(value));

Maybe you want your method to return an optional, which makes more sense.