edu.unh.sdb.datasource

Class CacheDataSource

java.lang.Object

edu.unh.sdb.datasource.DataCollection

edu.unh.sdb.datasource.DataSource

edu.unh.sdb.datasource.CacheDataSource

All Implemented Interfaces:

Indexable

Direct Known Subclasses:

BlockCacheDataSource, BlockListCacheDataSource

public abstract class CacheDataSource
extends DataSource

This is the abstract base class for all datasources that provide caching service for an underlying datasource.

Field Summary

Fields inherited from class edu.unh.sdb.datasource.DataSource

fdlDescriptor, isActivated, name, wsName

Fields inherited from class edu.unh.sdb.datasource.DataCollection

attributeOrder, axisOrdering, axisWeights, bounds, dataOrder, dimensionality, numAttributes, pointOrder, recordDesc

Constructor Summary

Constructors

Constructor and Description
CacheDataSource(java.lang.String name, DataSource ds, ISBounds iterationSpace) Create a CacheDataSource with a Cache associated with the argument datasource.

Method Summary

Methods

Modifier and Type	Method and Description
void	activate() Calls activate() for the datasource backing this cache.
void	datum(Datum datum, IndexSpaceID did) Load the data at the given index into the provided datum.
void	datum(Datum dtm, IndexSpaceID did, FieldIDMapper mp) Get the Datum and fill its values in the passed Datum at positions specified by the corresponding FieldIDMapper.
void	datum(Datum dtm, IndexSpaceID did, RecordSpec recSpec) Get the Datum and fill its values in the passed Datum at positions specified by the corresponding RecordSpec.
void	deactivate() Calls deactivate() for the datasource backing this cache.
ISBounds	getIterationSpace() Returns a copy of the iteration space expressed as an ISBounds.
DataSource	getSource() Return a reference to the DataSource that backs this CacheDataSource.
void	subblock(DataBlock queryBlock, ISBounds dstBounds, ISBounds srcBounds) Reads a subblock defined by srcBounds into the region of the Datablock argument defined by dstBounds.
void	subblock(DataBlock theBlock, ISBounds dstBounds, ISBounds srcBounds, FieldIDMapper mp) Reads a subblock defined by srcBounds into the region of the Datablock argument defined by dstBounds.
void	useBytesOnly() When this method is called, this subblock methods of this collection will read data as bytes, without performing any type conversion.

Methods inherited from class edu.unh.sdb.datasource.DataSource

checkActivated, clearCache, copyBestID, create, create, create, createRemote, createRemote, createRemoteClient, createRemoteClient, createRemoteDataSource, createRemoteDataSource, createRemoteDataSourceUDP, createRemoteUDP, createRemoteUDP, dumpData, equals, getFDLDescriptor, getMetadataCollection, getName, getStatistics, getValues, isActivated, main, setMetadataCollection, toString, toString

Methods inherited from class edu.unh.sdb.datasource.DataCollection

byteSize, computeOffset, computeOffset, copyBounds, createDataBlock, createDataBlock, createDataBlock, createDatum, createDatum, createDatum, createDatum, createDatum, createDatum, datum, datum, datum, datum, dim, getAttributeNames, getAxisOrdering, getAxisWeight, getAxisWeights, getBounds, getByte, getBytes, getBytes, getBytes, getBytes, getBytes, getBytes, getBytesByAttribute, getBytesByAttribute, getBytesByPoint, getBytesByPoint, getDataOrder, getDimensionsArray, getDouble, getDoubles, getDoubles, getDoubles, getDoubles, getDoubles, getDoubles, getDoublesByAttribute, getDoublesByAttribute, getDoublesByPoint, getDoublesByPoint, getFloat, getFloats, getFloats, getFloats, getFloats, getFloats, getFloats, getFloatsByAttribute, getFloatsByAttribute, getFloatsByPoint, getFloatsByPoint, getInt, getInts, getInts, getInts, getInts, getInts, getInts, getIntsByAttribute, getIntsByAttribute, getIntsByPoint, getIntsByPoint, getLowerBoundsArray, getNumAttributes, getRecordDescriptor, getShort, getShorts, getShorts, getShorts, getShorts, getShorts, getShorts, getShortsByAttribute, getShortsByAttribute, getShortsByPoint, getShortsByPoint, getStorageType, getUpperBoundsArray, getValues, getValuesByAttribute, getValuesByPoint, longVolume, setAxisOrdering, setBounds, setRecordDescriptor, size, subblock, subblock, subblock, subblock, subblock, subblock, subblock, subblock, subblock, subblock, volume

Methods inherited from class java.lang.Object

clone, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

CacheDataSource

public CacheDataSource(java.lang.String name,
               DataSource ds,
               ISBounds iterationSpace)

Create a CacheDataSource with a Cache associated with the argument datasource. The third argument specifies the DataSource subset that is cached.

Method Detail

useBytesOnly

public void useBytesOnly()

When this method is called, this subblock methods of this collection will read data as bytes, without performing any type conversion. This is meant to be used by servers, since they send raw bytes over the network anyway, and any conversion is wasted effort.

Overrides:

useBytesOnly in class DataCollection

activate

public void activate()

Calls activate() for the datasource backing this cache. This method should be overridden by child classes to create the cache object.

Overrides:

activate in class DataSource

deactivate

public void deactivate()

Calls deactivate() for the datasource backing this cache.

Overrides:

deactivate in class DataSource

getSource

public DataSource getSource()

Return a reference to the DataSource that backs this CacheDataSource.

getIterationSpace

public ISBounds getIterationSpace()

Returns a copy of the iteration space expressed as an ISBounds.

datum

public void datum(Datum datum,
         IndexSpaceID did)

Load the data at the given index into the provided datum.

Specified by:

datum in interface Indexable

Overrides:

datum in class DataCollection

datum

public void datum(Datum dtm,
         IndexSpaceID did,
         RecordSpec recSpec)

Get the Datum and fill its values in the passed Datum at positions specified by the corresponding RecordSpec.

Specified by:

datum in interface Indexable

Overrides:

datum in class DataCollection

datum

public void datum(Datum dtm,
         IndexSpaceID did,
         FieldIDMapper mp)

Get the Datum and fill its values in the passed Datum at positions specified by the corresponding FieldIDMapper.

Specified by:

datum in interface Indexable

Specified by:

datum in class DataCollection

subblock

public void subblock(DataBlock queryBlock,
            ISBounds dstBounds,
            ISBounds srcBounds)

Reads a subblock defined by srcBounds into the region of the Datablock argument defined by dstBounds.

Specified by:

subblock in interface Indexable

Specified by:

subblock in class DataCollection

subblock

public void subblock(DataBlock theBlock,
            ISBounds dstBounds,
            ISBounds srcBounds,
            FieldIDMapper mp)

Reads a subblock defined by srcBounds into the region of the Datablock argument defined by dstBounds. The FieldIDMapper argument determines the mapping between datums in the datasource and datums in the DataBlock.

Specified by:

subblock in interface Indexable

Specified by:

subblock in class DataCollection