Why collection literals?

Question

From the various online articles on Java 7 I have come to know that Java 7 will be having collection literals¹ like the following:

List

        

Answer 1

Another thing to note is that for lists this is very easy using var args, but have a little think about how you'd do it for a map. There is no way to supply pairs of arguments to a var args method, unless you introduce an extra Map.Entry object or something like that.

So using existing syntax you'd end up with

Map map = HashMap.of( new Entry( "key1", "value1" ), 
                                     new Entry( "key2", "value2" ) );

which would get very tiring very quickly.

Even if you go down the path of using a builder pattern (as we do) then it's pretty ugly

Map map = CollectionUtil.map()
                                        .put( "key1", "value1" )
                                        .put( "key2", "value2" )
                                        .map();