java - Which one is more efficient of using array list? -

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which 1 more efficient instantiate list ?

list<type> list = new arraylist<type>(2); list.add(new type("one")); list.add(new type("two"));

or

list<type> list = arrays.aslist(new type("one"), new type("two"));

they create different types of objects. new arraylist<>() creates java.util.arraylist, can added to, etc.

arrays.aslist() uses type happens called arraylist, nested type (java.util.arrays$arraylist) , doesn't allow elements added or removed. just wraps array.

now, if don't care differences, end 2 roughly-equivalent implementations, both wrapping array in list<> interface. surprised see them differ in performance in significant way - ever, if have specific performance concerns, should test them in particular context.


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