code: @SafeVarargs
      public static char min(final char... a) {
          N.checkArgNotNullOrEmpty(a, "The spcified array 'a' can not be null or empty");
  
          if (N.isNullOrEmpty(a)) {
              throw new IllegalArgumentException("The length of array can not be null or empty");
          }
  
          return min(a, 0, a.length);
      }
docs: <p>
  Returns the minimum value in an array.
  </p>
  
  @param a
  an array, must not be null or empty
  @return the minimum value in the array