code: public static <T extends Comparable<? super T>> T max(final T[] a) {
          N.checkArgNotNullOrEmpty(a, "The spcified array 'a' can not be null or empty");
  
          return max(a, 0, a.length);
      }
docs: Returns the maximum element in the array.
  
  @param a
  an array, must not be null or empty
  @return the maximum value in the array
  @throws IllegalArgumentException
  if <code>a</code> is <code>null</code> or empty.