code: @Override
  	public void setModel(int position, List<Chain> modelChains){
  		if (modelChains == null)
  			throw new IllegalArgumentException("trying to set model to null!");
  
  		for (Chain c: modelChains)
  			c.setStructure(this);
  
  		//System.out.println("model size:" + models.size());
  
  
  		Model model = new Model();
  		model.setChains(modelChains);
  
  		if (models.isEmpty()){
  			models.add(model);
  		} else {
  			models.set(position, model);
  		}
  	}
docs: {@inheritDoc}