org.apache.iotdb.tsfile.read.controller

Interface IMetadataQuerier

All Known Implementing Classes:

MetadataQuerierByFileImpl

public interface IMetadataQuerier

Method Summary

Modifier and Type	Method and Description
void	clear() clear caches (if used) to release memory.
List<TimeRange>	convertSpace2TimePartition(List<Path> paths, long spacePartitionStartPos, long spacePartitionEndPos) Convert the space partition constraint to the time partition constraint.
List<IChunkMetadata>	getChunkMetaDataList(Path path)
Map<Path,List<IChunkMetadata>>	getChunkMetaDataMap(List<Path> paths)
TSDataType	getDataType(Path path)
TsFileMetadata	getWholeFileMetadata()
void	loadChunkMetaDatas(List<Path> paths) this will load all chunk metadata of given paths into cache.

Method Detail

getChunkMetaDataList

List<IChunkMetadata> getChunkMetaDataList(Path path)
                                   throws IOException

Throws:

IOException

getChunkMetaDataMap

Map<Path,List<IChunkMetadata>> getChunkMetaDataMap(List<Path> paths)
                                            throws IOException

Throws:

IOException

getWholeFileMetadata

TsFileMetadata getWholeFileMetadata()

loadChunkMetaDatas

void loadChunkMetaDatas(List<Path> paths)
                 throws IOException

this will load all chunk metadata of given paths into cache.

call this method before calling getChunkMetaDataList() will accelerate the reading of chunk metadata, which will only read TsMetaData once

Throws:

IOException

getDataType

TSDataType getDataType(Path path)
                throws NoMeasurementException,
                       IOException

Returns:

the corresponding data type.

Throws:

NoMeasurementException - if the measurement not exists.

IOException

convertSpace2TimePartition

List<TimeRange> convertSpace2TimePartition(List<Path> paths,
                                           long spacePartitionStartPos,
                                           long spacePartitionEndPos)
                                    throws IOException

Convert the space partition constraint to the time partition constraint.

Parameters:

paths - selected paths in a query expression

spacePartitionStartPos - the start position of the space partition

spacePartitionEndPos - the end position of the space partition

Returns:

the converted time partition constraint

Throws:

IOException

clear

void clear()

clear caches (if used) to release memory.