Java ArrayList and HashMap on-the-fly

Question

Can someone please provide an example of creating a Java ArrayList and HashMap on the fly? So instead of doing an add() or put()

Answer 1

Arrays can be converted to Lists:

List al = Arrays.asList("vote", "for", "me"); //pandering

Note that this does not return an ArrayList but an arbitrary List instance (in this case it’s an Array.ArrayList)!

Bruno's approach works best and could be considered on the fly for maps. I prefer the other method for lists though (seen above):

Map map = new HashMap() {
 {
    put("key1", "value1");
    put("key2", "value2");
 }
};