code: private void arrayFillDefaultValue(Object arr) {
          if (null == arr)
              return;
          Class<?> clas = arr.getClass();
          Class<?> comp = Types.arrayElementType(clas);
          if ( !comp.isPrimitive() )
              if ( Types.arrayDimensions(clas) > 1 )
                  for ( int i = 0; i < Array.getLength(arr); i++ )
                      arrayFillDefaultValue(Array.get(arr, i));
              else
                  Arrays.fill((Object[]) arr, Primitive.unwrap(
                      Primitive.getDefaultValue(comp)));
      }
docs: Fill boxed numeric types with default numbers instead of nulls.
  @param arr the array to fill.