On Jan 2, 2013, at 3:18 PM, Kuu wrote:

> Focusing in the possible bug, in the SparseGrid2D class, in the function reduceObjectsAtLocations() (line 620), there is a call to the method getObjectsAtLocation() in the line 636, which may return a null value, the code is:
>  
> Bag temp = getObjectsAtLocation(xs[i],ys[i]);      //line 636 this can return 'null'
> int size = temp.numObjs;                    //line 637
>  
> And as you can see, if the value of "temp" is null, the line 637 will throw a null pointer exception as it's happening to me.

Hi Javier, I think you are correct.  The correct code should include a null check:

    // for each location...
    for(int i=0; i < len; i++)
        {
        Bag temp = getObjectsAtLocation(xs[i],ys[i]);
        if (temp != null)
            {
            final int size = temp.numObjs;
            final Object[] os = temp.objs;
            // for each object at that location...
            for(int j = 0; j < size; j++)
                {
                // add the result, the x, and the y
                result.add(os[j]);
                newXPos.add(xs[i]);
                newYPos.add(ys[i]);
                }
             }
        }

There are similar errors in SparseGrid3D and the two Continuous classes.

Sean