“Is Java Set ordered or not? ” is the most popular question asked when you interview for a Java Developer position. Many fail to answer it, and I have to admit I was one of the many.I have known the answer is “Yes and No” for a long time.No. HashSet is not ordered.Yes.TreeSet is ordered.If the interviewer continues with some follow up questions, I’m not confident that I know the answer then.Why is TreeSet ordered?Are there any other ordered Set implementations?As a growth-minded developer that always wants to improve, it is necessary to absorb some ...