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Thread: Object array to int array?

  1. #1
    Join Date
    Jul 2009
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    Default Object array to int array?

    ArrayList<Integer> in = new ArrayList<Integer>();
    //fill arraylist......
    int[] out;

    When using the ArrayList method toArray() it returns Object[], how would I go about converting this to int[]?

    out = in.toArray();

    Found java.lang.Object[] but expected int[]

    The most "obvious" solution i tried was a cast..but of course to no surprise i cant do that with an array.

    am i forced to pull each entry from the List using a loop?
    Last edited by rsala004; October 30th, 2009 at 12:59 AM.

  2. #2
    Super Moderator Json's Avatar
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    Jul 2009
    Warrington, United Kingdom
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    Default Re: Object array to int array?

    Yes thats correct, you will come across some issues doing this, however you can convert your list of Integer into an array of Integer with no big problems, its just the matter of converting it to an array of primitives you will need to loop through the indexes I believe.

    Auto (un)boxing is only so good I'm afraid

            final List<Integer> intList = new ArrayList<Integer>();
            final Integer[] intArray = intList.toArray(new Integer[intList.size()]);

    // Json

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