code: @Override public Integer getOffset(Integer id, Integer type)
     {
        Integer result = null;
  
        Map<Integer, Integer> map = m_table.get(id);
        if (map != null && type != null)
        {
           result = map.get(type);
        }
  
        return (result);
     }
docs: This method retrieves the offset of a given entry in the Var2Data block.
  Each entry can be uniquely located by the identifier of the object to
  which the data belongs, and the type of the data.
  
  @param id unique identifier of an entity
  @param type data type identifier
  @return offset of requested item