Lists.newArrayList vs new ArrayList

java generics guava
asela38 picture asela38 · Apr 2, 2012 · Viewed 91.2k times · Source

What is the best construction for creating a List of Strings? Is it Lists.newArrayList() (from guava) or new ArrayList()?

is it just a personal preference?
or is it just Type generic type inference?
or is there any theoretical or practical value in using Lists.newArrayList()?

Answer

Bozho picture Bozho · Apr 2, 2012

The guava builder saves typing the type arguments multiple times. Compare:

List<Foo<Bar, Baz>> list = Lists.newArrayList();
List<Foo<Bar, Baz>> list = new ArrayList<Foo<Bar, Baz>>();

In Java 7 it's a bit obsolete though, because you have the diamond operator:

List<Foo<Bar, Baz>> list = new ArrayList<>();

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