Module org.apache.jena.tdb

Package org.apache.jena.tdb1.index.ext

Class ExtHash

java.lang.Object

org.apache.jena.tdb1.index.ext.ExtHash

All Implemented Interfaces:

Iterable<Record>, org.apache.jena.atlas.lib.Closeable, org.apache.jena.atlas.lib.Sync, Index

public final class ExtHash
extends Object
implements Index

Extensible hashing http://en.wikipedia.org/wiki/Extendible_hashing

Field Summary

Fields

Modifier and Type	Field	Description
static boolean	Checking
static boolean	Debugging
static boolean	Logging

Constructor Summary

Constructors

Constructor	Description
ExtHash(PlainFile dictionaryBackingFile, RecordFactory recordFactory, BlockMgr blockMgrHashBuckets)

Method Summary

Modifier and Type	Method	Description
boolean	add(Record record)	Add a record - return true if an insertion was actually needed
void	check()	Perform checks on this index
void	clear()	Clear the index
void	close()	Close the index - can not be used again through this object
boolean	contains(Record key)	Return whether the index contains the record or not.
long	count()	Explicitly count the items in the hash table
static ExtHash	createMem(RecordFactory factory, int bucketSizeBytes)	Testing version - in-memory but inefficient as it uses a copy-in/copy-out block manager as a RAM disk
boolean	delete(Record record)	Delete a record.
final int	dictionarySize()
void	dump()
Record	find(Record key)	Find one record - and return the record actually in the index (may have a value part)
RecordFactory	getRecordFactory()	Get the Record factory associated with this index
boolean	isEmpty()	Answer whether the index is empty or not.
Iterator<Record>	iterator()	Iterate over the whole index
long	size()	Return size if known else return -1 : does not count the persistent storage
void	sync()
String	toString()

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Field Details

Debugging

public static boolean Debugging

Checking

public static boolean Checking

Logging

public static boolean Logging

Constructor Details

ExtHash

public ExtHash(PlainFile dictionaryBackingFile,
 RecordFactory recordFactory,
 BlockMgr blockMgrHashBuckets)

Method Details

createMem

public static ExtHash createMem(RecordFactory factory,
 int bucketSizeBytes)

Testing version - in-memory but inefficient as it uses a copy-in/copy-out block manager as a RAM disk

dictionarySize

public final int dictionarySize()

contains

public boolean contains(Record key)

Description copied from interface: Index

Return whether the index contains the record or not.

Specified by:

contains in interface Index

find

public Record find(Record key)

Description copied from interface: Index

Find one record - and return the record actually in the index (may have a value part)

Specified by:

find in interface Index

add

public boolean add(Record record)

Description copied from interface: Index

Add a record - return true if an insertion was actually needed

Specified by:

add in interface Index

delete

public boolean delete(Record record)

Description copied from interface: Index

Delete a record. Return true if a record was actually removed

Specified by:

delete in interface Index

getRecordFactory

public RecordFactory getRecordFactory()

Description copied from interface: Index

Get the Record factory associated with this index

Specified by:

getRecordFactory in interface Index

iterator

public Iterator<Record> iterator()

Description copied from interface: Index

Iterate over the whole index

Specified by:

iterator in interface Index

Specified by:

iterator in interface Iterable<Record>

isEmpty

public boolean isEmpty()

Description copied from interface: Index

Answer whether the index is empty or not. May return false for unknown or meaningless

Specified by:

isEmpty in interface Index

clear

public void clear()

Description copied from interface: Index

Clear the index

Specified by:

clear in interface Index

size

public long size()

Description copied from interface: Index

Return size if known else return -1 : does not count the persistent storage

Specified by:

size in interface Index

count

public long count()

Explicitly count the items in the hash table

sync

public void sync()

Specified by:

sync in interface org.apache.jena.atlas.lib.Sync

close

public void close()

Description copied from interface: Index

Close the index - can not be used again through this object

Specified by:

close in interface org.apache.jena.atlas.lib.Closeable

Specified by:

close in interface Index

toString

public String toString()

Overrides:

toString in class Object

dump

public void dump()

check

public void check()

Description copied from interface: Index

Perform checks on this index

Specified by:

check in interface Index