blueflood-core/src/main/java/com/rackspacecloud/blueflood/io/astyanax/APreaggregatedMetricsRW.java
@Override
    public <T extends Rollup> Points<T> getDataToRollup(final Locator locator,
                                                        RollupType rollupType,
                                                        Range range,
                                                        String columnFamilyName) throws IOException {
        ColumnFamily cf = CassandraModel.getColumnFamily(columnFamilyName);
        // a quick n dirty hack, this code will go away someday
        Granularity granularity = CassandraModel.getGranularity(cf);
        Class<? extends Rollup> rollupClass = RollupType.classOf(rollupType, granularity);
        return AstyanaxReader.getInstance().getDataToRoll(rollupClass, locator, range, cf);
    }
@Override
    public <T extends Rollup> Points<T> getDataToRollup(final Locator locator,
                                                        RollupType rollupType,
                                                        Range range,
                                                        String columnFamilyName) throws IOException {
        ColumnFamily cf = CassandraModel.getColumnFamily(columnFamilyName);
        // a quick n dirty hack, this code will go away someday
        Granularity granularity = CassandraModel.getGranularity(cf);
        Class<? extends Rollup> rollupClass = RollupType.classOf(rollupType, granularity);
        return AstyanaxReader.getInstance().getDataToRoll(rollupClass, locator, range, cf);
    }
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
@param <T> the type of Rollup object
@return