public static int[] validate2NonNegative(int[] data, boolean allowSz1, String paramName) {
        validateNonNegative(data, paramName);
        return validate2(data, allowSz1, paramName);
    }
public static int [ ] validate2NonNegative ( int [ ] data , boolean allowSz1 , String paramName ) { validateNonNegative ( data , paramName ) ; return validate2 ( data , allowSz1 , paramName ) ; }
Reformats the input array to a length 2 array and checks that all values are >= 0.

If the array is length 1, returns [a, a]
If the array is length 2, returns the array.

@param data An array
@param paramName The param name, for error reporting
@return An int array of length 2 that represents the input