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

You mean like this?

public List buildList(String first, String second)
{
     List ret = new ArrayList();
     ret.add(first);
     ret.add(second);
     return ret;
}

...

List names = buildList("Jon", "Marc");

Or are you interested in the ArrayList constructor which takes a Collection? For example:

String[] items = new String[] { "First", "Second", "Third" };
// Here's one way of creating a List...
Collection itemCollection = Arrays.asList(items);
// And here's another
ArrayList itemList = new ArrayList(itemCollection);