Converting a TreeSet to ArrayList?

ArrayList has a convenience method addAll that fits the bill nicely:

final Set<Object> set = ...
List<Object> list = new ArrayList<Object>(someBigNum);
list.addAll(set);

How about this:

new ArrayList<T>(set);

For Java 7 and later, this can be simplified, as type arguments <T> can be replaced with diamond type <>:

new ArrayList<>(set);

In case one uses Eclipse Collections, which has super-powers and is developed by Goldman Sachs, there is toList():

MutableSortedSet<Object> set = SortedSets.mutable.empty();
...
return set.toList();

Providing a comparator is also possible:

MutableSortedSet<Object> set = SortedSets.mutable.of(comparator);
...
return set.toList();

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