org.sensorhub.api.persistence

Interface IBasicStorage

All Known Subinterfaces:

IObsStorage, IObsStorageModule<ConfigType>, IRecordStorageModule<ConfigType>

public interface IBasicStorage

Storage for one or more data streams coming from a single source. (for instance, the source can be a sensor, a service or a process)
This also supports storing lineage information if a description of the data source is provided.

Since:

Nov 27, 2014

Method Summary

Modifier and Type	Method and Description
void	addRecordStore(java.lang.String name, DataComponent recordStructure, DataEncoding recommendedEncoding) Adds a data store for a new record type in this storage
DataBlock	getDataBlock(DataKey key) Retrieves raw data block with the specified key
java.util.Iterator<DataBlock>	getDataBlockIterator(IDataFilter filter) Gets iterator of raw data blocks matching the specified filter
AbstractProcess	getDataSourceDescriptionAtTime(double time) Retrieves data source description valid at specified time
java.util.List<AbstractProcess>	getDataSourceDescriptionHistory(double startTime, double endTime) Retrieves history of data source description for the given time period
AbstractProcess	getLatestDataSourceDescription() Retrieves latest data source description (i.e.
int	getNumMatchingRecords(IDataFilter filter, long maxCount) Computes the (potentially approximate) number of records matching the given filter. Since the returned value can be approximate and the number of matching records can change before or even during the actual call to getRecordIterator(IDataFilter), the exact number of records can only be obtained by counting the records returned by the iterator next() function.
int	getNumRecords(java.lang.String recordType) Helper method to retrieve the total number of method for the specified record type
java.util.Iterator<? extends IDataRecord>	getRecordIterator(IDataFilter filter) Gets iterator of records matching the specified filter
java.util.Iterator<double[]>	getRecordsTimeClusters(java.lang.String recordType) Retrieves time boundaries of data clusters (i.e.
double[]	getRecordsTimeRange(java.lang.String recordType) Retrieves time range spanned by all records of the specified type
java.util.Map<java.lang.String,? extends IRecordStoreInfo>	getRecordStores() Gets the list of available record types in this storage
boolean	isReadSupported()
boolean	isWriteSupported()
void	removeDataSourceDescription(double time) Removes data source description valid at specified time
void	removeDataSourceDescriptionHistory(double startTime, double endTime) Removes data source descriptions whose validity periods lie within the given time period
void	removeRecord(DataKey key) Removes record with the specified key
int	removeRecords(IDataFilter filter) Removes all records matching the filter
void	storeDataSourceDescription(AbstractProcess process) Stores a new data source description into storage.
void	storeRecord(DataKey key, DataBlock data) Persists data block in storage
void	updateDataSourceDescription(AbstractProcess process) Update the data source description in storage.
void	updateRecord(DataKey key, DataBlock data) Updates record with specified key with new data

Method Detail

getLatestDataSourceDescription

AbstractProcess getLatestDataSourceDescription()

Retrieves latest data source description (i.e. most recent version)

Returns:

SensorML process description

getDataSourceDescriptionHistory

java.util.List<AbstractProcess> getDataSourceDescriptionHistory(double startTime,
                                                                double endTime)

Retrieves history of data source description for the given time period

Parameters:

startTime - lower bound of the time period

endTime - upper bound of the time period

Returns:

list of SensorML process descriptions (with disjoint time validity periods)

getDataSourceDescriptionAtTime

AbstractProcess getDataSourceDescriptionAtTime(double time)

Retrieves data source description valid at specified time

Parameters:

time -

Returns:

SensorML process description

storeDataSourceDescription

void storeDataSourceDescription(AbstractProcess process)

Stores a new data source description into storage. Validity period must not overlap with existing descriptions

Parameters:

process - SensorML process description to store

updateDataSourceDescription

void updateDataSourceDescription(AbstractProcess process)

Update the data source description in storage. Validity period must be exactly the same as one in storage

Parameters:

process - SensorML process description to update

removeDataSourceDescription

void removeDataSourceDescription(double time)

Removes data source description valid at specified time

Parameters:

time - any time falling within the validity period of the description version to remove

removeDataSourceDescriptionHistory

void removeDataSourceDescriptionHistory(double startTime,
                                        double endTime)

Removes data source descriptions whose validity periods lie within the given time period

Parameters:

startTime - lower bound of the time period

endTime - upper bound of the time period

getRecordStores

java.util.Map<java.lang.String,? extends IRecordStoreInfo> getRecordStores()

Gets the list of available record types in this storage

Returns:

map of name to data store instance

addRecordStore

void addRecordStore(java.lang.String name,
                    DataComponent recordStructure,
                    DataEncoding recommendedEncoding)

Adds a data store for a new record type in this storage

Parameters:

name - name of record type (should match output name of the data source)

recordStructure - SWE data component describing the record structure

recommendedEncoding - recommended encoding for this record type

getNumRecords

int getNumRecords(java.lang.String recordType)

Helper method to retrieve the total number of method for the specified record type

Parameters:

recordType - name of record type

Returns:

total number of records

getRecordsTimeRange

double[] getRecordsTimeRange(java.lang.String recordType)

Retrieves time range spanned by all records of the specified type

Parameters:

recordType - name of record type

Returns:

array of length 2 in the form [minTime maxTime] or [NaN NaN] if no records of this type are available

getRecordsTimeClusters

java.util.Iterator<double[]> getRecordsTimeClusters(java.lang.String recordType)

Retrieves time boundaries of data clusters (i.e. this allows to detect temporal holes in the data)

Parameters:

recordType - name of record type

Returns:

A read-only iterator among time periods delimiting clusters of data

getDataBlock

DataBlock getDataBlock(DataKey key)

Retrieves raw data block with the specified key

Parameters:

key - Record key

Returns:

data block or null if no record with the specified key was found

getDataBlockIterator

java.util.Iterator<DataBlock> getDataBlockIterator(IDataFilter filter)

Gets iterator of raw data blocks matching the specified filter

Parameters:

filter - filtering parameters

Returns:

A read-only iterator among data blocks matching the filter

getRecordIterator

java.util.Iterator<? extends IDataRecord> getRecordIterator(IDataFilter filter)

Gets iterator of records matching the specified filter

Parameters:

filter - filtering parameters

Returns:

A read-only iterator among records matching the filter

getNumMatchingRecords

int getNumMatchingRecords(IDataFilter filter,
                          long maxCount)

Computes the (potentially approximate) number of records matching the given filter.
Since the returned value can be approximate and the number of matching records can change before or even during the actual call to getRecordIterator(IDataFilter), the exact number of records can only be obtained by counting the records returned by the iterator next() function.

Parameters:

filter - filtering parameters

maxCount - counting will stop once this threshold is reached

Returns:

number of matching records

storeRecord

void storeRecord(DataKey key,
                 DataBlock data)

Persists data block in storage

Parameters:

key - key object to associate to record

data - actual record data

updateRecord

void updateRecord(DataKey key,
                  DataBlock data)

Updates record with specified key with new data

Parameters:

key - key of record to update

data - new data block to assign to the record

removeRecord

void removeRecord(DataKey key)

Removes record with the specified key

Parameters:

key - record key

removeRecords

int removeRecords(IDataFilter filter)

Removes all records matching the filter

Parameters:

filter - filtering parameters

Returns:

number of deleted records

isReadSupported

boolean isReadSupported()

Returns:

true if read operations are supported by this storage, false otherwise

isWriteSupported

boolean isWriteSupported()

Returns:

true if write operations are supported by this storage, false otherwise