code: public Operation resize(long sizeGb, OperationOption... options) {
      return compute.resize(getDiskId(), sizeGb, options);
    }
docs: Resizes this disk to the requested size. The new size must be larger than the previous one.
  
  @return a zone operation if the resize request was issued correctly, {@code null} if this disk
  was not found
  @throws ComputeException upon failure or if the new disk size is smaller than the previous one