Initialization of an ArrayList in one line

Question

I wanted to create a list of options for testing purposes. At first, I did this:

ArrayList places = new ArrayList();
places.add(\         


        

Answer 1

In Java, you can't do

ArrayList places = new ArrayList( Arrays.asList("Buenos Aires", "Córdoba", "La Plata"));

As was pointed out, you'd need to do a double brace initialization:

List places = new ArrayList() {{ add("x"); add("y"); }};

But this may force you into adding an annotation @SuppressWarnings("serial") or generate a serial UUID which is annoying. Also most code formatters will unwrap that into multiple statements/lines.

Alternatively you can do

List places = Arrays.asList(new String[] {"x", "y" });

but then you may want to do a @SuppressWarnings("unchecked").

Also according to javadoc you should be able to do this:

List stooges = Arrays.asList("Larry", "Moe", "Curly");

But I'm not able to get it to compile with JDK 1.6.