uniq

In one word, what's wrong with this method?
Idea is that it should return a list that contains no duplicates

Code:

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private List<String> uniqueArguments(ArrayList<String> arrayList) {
  List<String> noDups = (List<String>) new HashSet<String>(arrayList);
                return noDups;
}

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In anticipation of why i think there is something wrong with it, the following is a warning i get "Type safety: Unchecked cast from HashSet<String> to List<String>"

And also, it does not work :(
Exception in thread "main" java.lang.ClassCastException: java.util.HashSet cannot be cast to java.util.List

Code:

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private List<String> uniqueArguments(ArrayList<String> arrayList) {
        System.out.println(arrayList);
        HashSet<String> noDups = new HashSet<String>(arrayList);
        System.out.println(noDups);
        return (List<String>) noDups;
}

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1 more comment, sysouts work and print what's expected, but still
Exception in thread "main" java.lang.ClassCastException: java.util.HashSet cannot be cast to java.util.List

You cannot cast Hashset to List.

Ok ... any advise on how to go about it?

Have a List, need to check if it contains unqiue elements

Quote:

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Originally Posted by mac

Ok ... any advise on how to go about it?

Have a List, need to check if it contains unqiue elements

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A you created a Set given a List so you can create another List given a Set.

kind regards,

Jos

Quote:

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Originally Posted by JosAH

A you created a Set given a List so you can create another List given a Set.

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That's all.