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Thread: Defining an Array of ArryaList of ArrayList

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    Default Defining an Array of ArryaList of ArrayList

    I have this :
    public final static AxisAlignedBB BASE_AACB = new AxisAlignedBB		(0.0D, 0.0D, 0.0D,		1.0D , 0.5D, 1.0D);
    public final static AxisAlignedBB NORTH_QTR_AACB = new AxisAlignedBB 	(0.0D  , 0.5D,  0.0D	, 1.0D , 1.0D,  0.5D);
    public final static AxisAlignedBB WEST_RAIL_AACB = new AxisAlignedBB	(0.0D,	0.0D , 0.0D 	, 0.07D, 1.3D, 1.0D);	
     
    public final static ArrayList<AxisAlignedBB> STAIR_STEPS_NORTH = new ArrayList<AxisAlignedBB>(Arrays.asList(BASE_AACB, NORTH_QTR_AACB));
    .
    .
    .
     
     
    	public final static ArrayList[] STAIR_STEPS_ALL = {STAIR_STEPS_NORTH, STAIR_STEPS_SOUTH, STAIR_STEPS_WEST, STAIR_STEPS_EAST};
    I get a warning about raw types ( on the = {STAIR_STEPS_NORTH, STAIR_STEPS_SOUTH, STAIR_STEPS_WEST, STAIR_STEPS_EAST} part)

    How can i define STAIR_STEPS_ALL[] correctly without rawtypes?

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    Default Re: Defining an Array of ArryaList of ArrayList

    You can't create arrays with a generic component type.
    Use a collection like List in place of the array.
    If you don't understand my answer, don't ignore it, ask a question.

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    Default Re: Defining an Array of ArryaList of ArrayList

    You can do the following:

    public final static ArrayList<?>[]				STAIR_STEPS_ALL	  = {
             STAIR_STEPS_NORTH, STAIR_STEPS_SOUTH, STAIR_STEPS_WEST,
             STAIR_STEPS_EAST
       };

    However, when you retrieve one you will have to cast it. The SuppressWarnings statement isn't required as it just gets rid of a warning.

      public static void main(String[] args) {
    	   @SuppressWarnings("unchecked")
    	   ArrayList<AxisAlignedBB> b = (ArrayList<AxisAlignedBB>)STAIR_STEPS_ALL[0];
       }


    But there is really no point to all of that. Since you have to cast you may as well declare the array as type Object and then cast as I did up above.

    Regards,
    Jim
    Last edited by jim829; November 22nd, 2018 at 03:23 PM.

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