How to lowercase every element of a collection efficiently?

Question

What\'s the most efficient way to lower case every element of a List or Set?

My idea for a List:

final List strings = new ArrayList<         


        

Answer 1

Well, there is no real elegant solution due to two facts:

• Strings in Java are immutable
• Java gives you no real nice map(f, list) function as you have in functional languages.

Asymptotically speaking, you can't get a better run time than your current method. You will have to create a new string using toLowerCase() and you will need to iterate by yourself over the list and generate each new lower-case string, replacing it with the existing one.