How to convert a Collection to List?

Question

I am using TreeBidiMap from the Apache Collections library. I want to sort this on the values which are doubles.

My method is to retrieve a

Answer 1

List list = new ArrayList(coll);
Collections.sort(list);

As Erel Segal Halevi says below, if coll is already a list, you can skip step one. But that would depend on the internals of TreeBidiMap.

List list;
if (coll instanceof List)
  list = (List)coll;
else
  list = new ArrayList(coll);