blueflood-core/src/main/java/com/rackspacecloud/blueflood/io/datastax/DAbstractMetricsRW.java
@Override
    public Points getDataToRollup(final Locator locator,
                                  RollupType rollupType,
                                  Range range,
                                  String columnFamilyName) throws IOException {
        Timer.Context ctx = Instrumentation.getReadTimerContext(columnFamilyName);
        try {
            // read the rollup object from the proper IO class
            DAbstractMetricIO io = getIO( rollupType.name().toLowerCase(), CassandraModel.getGranularity( columnFamilyName ) );

            Table<Locator, Long, Object> locatorTimestampRollup = io.getRollupsForLocator( locator, columnFamilyName, range );

            Points points = new Points();
            for (Table.Cell<Locator, Long, Object> cell : locatorTimestampRollup.cellSet()) {
                points.add( createPoint( cell.getColumnKey(), cell.getValue()));
            }
            return points;
        } catch( Exception e ) {

            Instrumentation.markReadError();
            LOG.error( String.format( "Unable to read locator=%s rolluptype=%s columnFamilyName=%s for rollup",
                    locator, rollupType.name(), columnFamilyName ), e );

            throw new IOException( e );
        }
        finally {
            ctx.stop();
        }
    }
@Override
    public Points getDataToRollup(final Locator locator,
                                  RollupType rollupType,
                                  Range range,
                                  String columnFamilyName) throws IOException {
        Timer.Context ctx = Instrumentation.getReadTimerContext(columnFamilyName);
        try {
            // read the rollup object from the proper IO class
            DAbstractMetricIO io = getIO( rollupType.name().toLowerCase(), CassandraModel.getGranularity( columnFamilyName ) );

            Table<Locator, Long, Object> locatorTimestampRollup = io.getRollupsForLocator( locator, columnFamilyName, range );

            Points points = new Points();
            for (Table.Cell<Locator, Long, Object> cell : locatorTimestampRollup.cellSet()) {
                points.add( createPoint( cell.getColumnKey(), cell.getValue()));
            }
            return points;
        } catch( Exception e ) {

            Instrumentation.markReadError();
            LOG.error( String.format( "Unable to read locator=%s rolluptype=%s columnFamilyName=%s for rollup",
                    locator, rollupType.name(), columnFamilyName ), e );

            throw new IOException( e );
        }
        finally {
            ctx.stop();
        }
    }
Fetches a {@link com.rackspacecloud.blueflood.types.Points} object for a
particular locator and rollupType from the specified column family and
range

@param locator
@param rollupType
@param range
@param columnFamilyName
@return