Why doesn't java.util.HashSet have a get(Object o) method?

Question

I\'ve seen other questions about getting objects from Set\'s based on index value and I understand why that is not possible. But I haven\'t been able to find a

Answer 1

get(Object o) is useful when we have one information linked to other information just like key value pair found in HashMap .So using get() method on one information we can get the second information or vice-versa.

Now, if HashSet provides get(Object o) method you need to pass an object. So if you have the object to pass to the get(Object o) method that means you already have the object, then what is need of get(Object o) method.