How do I sort a set in Java?

In Java, I have a set, and I want to turn it into a sorted list. Is there a method in the collections package that will do this for me?

From stackoverflow

• There's no single method to do that. Use this:

  @SuppressWarnings("unchecked")
  public static <T extends Comparable> List<T> asSortedList(Collection<T> collection) {
    T[] array = collection.toArray(
      (T[])new Comparable[collection.size()]);
    Arrays.sort(array);
    return Arrays.asList(array);
  }
  

  CookieOfFortune : There is also a Collections.sort function, but I think it does the same thing. +1 anyways.

  Jeremy Stein : Collections.sort takes a list as a parameter.

• sorted set:
  return new TreeSet(setIWantSorted)

  Alex B : This was my first thought, but the asker wanted a List

  Jonik : @Alex: This approach can still be used; return new ArrayList(new TreeSet(setIWantSorted))

• ...you answered your own question 38 seconds after you had asked it?

  List myList = new ArrayList(collection); Collections.sort(myList); should do the trick however. Add flavour with Generics where applicable.

  Jeremy Stein : I had a useful snippet I wanted to donate to the community. When I searched for the information, I couldn't find it. I was trying to make the next person's job easier. http://stackoverflow.com/questions/18557/how-does-stackoverflow-work-the-unofficial-faq#119658

  Seb : Yeah, sure, but that link you provided is actually talking about a _real_ questions (i.e. those for which don't have the answer, then find it). Your question here was only to give the answer... I could actually enter hundreds of questions and answer myself; that's not the point!

  Michael Myers : @Seb: I disagree. I don't see anything wrong with this question. It obviously wasn't an extremely simple question, and now he knows a better way than he did before!

  Jeremy Stein : It *was* a real question, but I found the answer myself after Google came up short. Stackoverflow didn't exist at the time. I had it posted on my website and it helped someone else, so I thought it might be useful here.

• The answer provided by the OP is not the best. It is inefficient, as it creates a new List and an unnecessary new array. Also, it raises "unchecked" warnings because of the type safety issues around generic arrays.

  Instead, use something like this:

  public static
  <T extends Comparable<? super T>> List<T> asSortedList(Collection<T> c) {
    List<T> list = new ArrayList<T>(c);
    java.util.Collections.sort(list);
    return list;
  }
  

  Jeremy Stein : Thanks! That SuppressWarnings always bothered me.

• You can convert a set into a ArrayList. where you can sort ArrayList using Collections.sort(List);

  here is the code..

      keySet = (Set) map.keySet();
  
      System.out.println("key Set  -----------------------> " + keySet);
  
      ArrayList list = new ArrayList(keySet);
  
      System.out.println("List ----------------------> "+ list);
  
      Collections.sort(list);
  

  Tim : How is this different from the accepted answer?