code: public long byteSize()
  	{
  
  		long byteSize = 3;
  
  		int size = parts.size();
  
  		for (int i = 0; i < size; i++) {
  			byteSize += this.parts.get(i).byteSize();
  		}
  
  		return byteSize;
  	}
docs: Returns an estimation of the size used to stored the data.
  
  @return estimated size