Difference between Map<String, String> and Map<>?

Question

What is he difference between two approaches of instantiating a map:

  Map<String, String> map = new TreeMap<String, String>();

and

  Map<String, String> map = new TreeMap<>();

and which one is better?

Eran · Accepted Answer · 2015-09-17 11:54:44Z

11

They are equivalent. The second syntax (known as the diamond operator) was added in Java 7 and allows you to type less code.

answered Sep 17, 2015 at 11:54

Eran

395k57 gold badges726 silver badges793 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

Dhanesh Khurana Over a year ago

I have one more question why Map<String, Map<String, String>> map = new TreeMap<String, HashMap<String, String>>() produces compile time error whilst Map<String, Map<String, String>> map = new TreeMap<>() does not!

Eran Over a year ago

@DhaneshKhurana In Map<String, Map<String, String>> map = new TreeMap<String, HashMap<String, String>>(); the assigned instance doesn't match the type of the variable. It should be Map<String, Map<String, String>> map = new TreeMap<String, Map<String, String>>();

Collectives™ on Stack Overflow

Difference between Map<String, String> and Map<>?

1 Answer 1

2 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

2 Comments

Your Answer

Sign up or log in

Post as a guest

Related