public
    <T extends Data> T getDataFromEntity(
            final Class<T> someDataType, final long someEntityId )
            throws NoSuchEntityException,
                   NoSuchDataOnEntityException {
        //local vars
        T data;
        THashMap<Class<? extends Data>, Data> entiyDataMap;
        //
        DataCore db = _dataCenter.getDataCore();

        //check if there is an entity registered under the given id
        if( ! db.getEntity_Data_Table().containsKey( someEntityId ) ) {
            //if not throw an exception
            throw new NoSuchEntityException( someEntityId );
        }

        //retrieve the data for this entity
        entiyDataMap = db.getEntity_Data_Table().get( someEntityId );
        //check whether this entity holds the given type of data 
        if( ! entiyDataMap.containsKey( someDataType ) ) {
            //if not throw an exception
            throw new NoSuchDataOnEntityException( someDataType, someEntityId );
        }

        //retrieve the data
        data = (T)entiyDataMap.get( someDataType );

        //return it
        return data;
    }