What is the best way of using Arrays.asList() to initialize a List [duplicate]

Answer 1

Case 2 is better performance-wise BUT: it returns a List with an immutable size. Meaning you cannot add/remove elements to/from it:

Returns a fixed-size list backed by the specified array. (Changes to the returned list "write through" to the array.)

Arrays#asList

Answer 2

I think case 2 is like creating new String[10]. You cannot change size but you can change elements. Case 1 allows you to do both.

This shows what you can do with case 2: http://grepcode.com/file/repository.grepcode.com/java/root/jdk/openjdk/8u40-b25/java/util/Arrays.java#Arrays.ArrayList