code: public <D extends DataSet<?>> void add(int id, D set) {
  		cacheSetType(id, SetType.DATA_SET);
  		dataSets.put(id, set);
  	}
docs: Adds the given {@link DataSet} to this cache for the given ID.
  
  @param id  Set ID
  @param set DataSet to add
  @param <D> DataSet class