org.neo4j.kernel.impl.nioneo.store
Class AbstractDynamicStore

java.lang.Object
  org.neo4j.kernel.impl.nioneo.store.CommonAbstractStore
      org.neo4j.kernel.impl.nioneo.store.AbstractDynamicStore

All Implemented Interfaces:

RecordStore<DynamicRecord>, Store

Direct Known Subclasses:

DynamicArrayStore, DynamicStringStore

public abstract class AbstractDynamicStore
extends CommonAbstractStore
implements Store, RecordStore<DynamicRecord>

An abstract representation of a dynamic store. The difference between a normal AbstractStore and a AbstractDynamicStore is that the size of a record/entry can be dynamic.

Instead of a fixed record this class uses blocks to store a record. If a record size is greater than the block size the record will use one or more blocks to store its data.

A dynamic store don't have a IdGenerator because the position of a record can't be calculated just by knowing the id. Instead one should use a AbstractStore and store the start block of the record located in the dynamic store. Note: This class makes use of an id generator internally for managing free and non free blocks.

Note, the first block of a dynamic store is reserved and contains information about the store.

Nested Class Summary

Nested classes/interfaces inherited from interface org.neo4j.kernel.impl.nioneo.store.RecordStore

RecordStore.Processor

Field Summary

protected static int

BLOCK_HEADER_SIZE

Fields inherited from class org.neo4j.kernel.impl.nioneo.store.CommonAbstractStore

ALL_STORES_VERSION, logger, storageFileName, UNKNOWN_VERSION

Fields inherited from interface org.neo4j.kernel.impl.nioneo.store.RecordStore

IN_USE

Constructor Summary

AbstractDynamicStore(String fileName, Map<?,?> config, IdType idType)

Method Summary

protected Collection<DynamicRecord>	allocateRecords(long startBlock, byte[] src)
protected static void	createEmptyStore(String fileName, int baseBlockSize, String typeAndVersionDescriptor, IdGeneratorFactory idGeneratorFactory, IdType idType) Creates a new empty store.
protected long	figureOutHighestIdInUse()
DynamicRecord	forceGetRaw(long id)
DynamicRecord	forceGetRecord(long id)
void	forceUpdateRecord(DynamicRecord record)
void	freeBlockId(long blockId) Makes a previously used block available again.
int	getBlockSize() Returns the byte size of each block for this dynamic store
protected int	getEffectiveRecordSize()
Collection<DynamicRecord>	getLightRecords(long startBlockId)
DynamicRecord	getRecord(long id)
int	getRecordHeaderSize()
Collection<DynamicRecord>	getRecords(long startBlockId)
int	getRecordSize()
static int	getRecordSize(int dataSize) Calculate the size of a dynamic record given the size of the data block.
protected boolean	isRecordInUse(ByteBuffer buffer)
void	logIdUsage(StringLogger logger)
void	makeHeavy(DynamicRecord record)
long	nextBlockId() Returns next free block.
protected void	readAndVerifyBlockSize()
protected void	rebuildIdGenerator() Rebuilds the internal id generator keeping track of what blocks are free or taken.
String	toString()
void	updateRecord(DynamicRecord record)
protected void	verifyFileSizeAndTruncate()

Methods inherited from class org.neo4j.kernel.impl.nioneo.store.CommonAbstractStore

acquireWindow, buildTypeDescriptorAndVersion, calculateMappedMemory, checkStorage, checkVersion, close, closeIdGenerator, closeStorage, createIdGenerator, flushAll, freeId, getConfig, getFileChannel, getFileSystem, getHighestPossibleIdInUse, getHighId, getIdType, getIfMemoryMapped, getNumberOfIdsInUse, getStorageFileName, getStoreDir, getStoreOk, getTypeAndVersionDescriptor, getTypeDescriptor, getWindowPoolStats, initStorage, isInRecoveryMode, loadStorage, logVersions, longFromIntAndMod, makeStoreOk, nextId, openIdGenerator, openIdGenerator, openReadOnlyIdGenerator, rebuildIdGenerators, registerIdFromUpdateRecord, releaseFileLockAndCloseFileChannel, releaseWindow, setHighId, setRecovered, setStoreNotOk, setWindowPool, unsetRecovered, updateHighId, verifyCorrectTypeDescriptorAndVersion

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.neo4j.kernel.impl.nioneo.store.Store

getHighestPossibleIdInUse, getNumberOfIdsInUse, getTypeDescriptor, getWindowPoolStats, nextId

Methods inherited from interface org.neo4j.kernel.impl.nioneo.store.RecordStore

accept, close, getHighId

Field Detail

BLOCK_HEADER_SIZE

protected static final int BLOCK_HEADER_SIZE

See Also:

Constant Field Values

Constructor Detail

AbstractDynamicStore

public AbstractDynamicStore(String fileName,
                            Map<?,?> config,
                            IdType idType)

Method Detail

createEmptyStore

protected static void createEmptyStore(String fileName,
                                       int baseBlockSize,
                                       String typeAndVersionDescriptor,
                                       IdGeneratorFactory idGeneratorFactory,
                                       IdType idType)

Creates a new empty store. A factory method returning an implementation should make use of this method to initialize an empty store. Block size must be greater than zero. Not that the first block will be marked as reserved (contains info about the block size). There will be an overhead for each block of AbstractDynamicStore.BLOCK_HEADER_SIZE bytes.

This method will create a empty store with descriptor returned by the CommonAbstractStore.getTypeDescriptor(). The internal id generator used by this store will also be created.

Parameters:

fileName - The file name of the store that will be created

blockSize - The number of bytes for each block

typeAndVersionDescriptor - The type and version descriptor that identifies this store

Throws:

IOException - If fileName is null or if file exists or illegal block size

getEffectiveRecordSize

protected int getEffectiveRecordSize()

Specified by:

getEffectiveRecordSize in class CommonAbstractStore

getRecordSize

public int getRecordSize()

Specified by:

getRecordSize in interface RecordStore<DynamicRecord>

getRecordHeaderSize

public int getRecordHeaderSize()

Specified by:

getRecordHeaderSize in interface RecordStore<DynamicRecord>

verifyFileSizeAndTruncate

protected void verifyFileSizeAndTruncate()
                                  throws IOException

Specified by:

verifyFileSizeAndTruncate in class CommonAbstractStore

Throws:

IOException

readAndVerifyBlockSize

protected void readAndVerifyBlockSize()
                               throws IOException

Specified by:

readAndVerifyBlockSize in class CommonAbstractStore

Throws:

IOException

getBlockSize

public int getBlockSize()

Returns the byte size of each block for this dynamic store

Returns:

The block size of this store

nextBlockId

public long nextBlockId()

Returns next free block.

Returns:

The next free block

Throws:

IOException - If capacity exceeded or closed id generator

freeBlockId

public void freeBlockId(long blockId)

Makes a previously used block available again.

Parameters:

blockId - The id of the block to free

Throws:

IOException - If id generator closed or illegal block id

getRecordSize

public static int getRecordSize(int dataSize)

Calculate the size of a dynamic record given the size of the data block.

Parameters:

dataSize - the size of the data block in bytes.

Returns:

the size of a dynamic record.

updateRecord

public void updateRecord(DynamicRecord record)

Specified by:

updateRecord in interface RecordStore<DynamicRecord>

forceUpdateRecord

public void forceUpdateRecord(DynamicRecord record)

Specified by:

forceUpdateRecord in interface RecordStore<DynamicRecord>

allocateRecords

protected Collection<DynamicRecord> allocateRecords(long startBlock,
                                                    byte[] src)

getLightRecords

public Collection<DynamicRecord> getLightRecords(long startBlockId)

makeHeavy

public void makeHeavy(DynamicRecord record)

isRecordInUse

protected boolean isRecordInUse(ByteBuffer buffer)

getRecord

public DynamicRecord getRecord(long id)

Specified by:

getRecord in interface RecordStore<DynamicRecord>

forceGetRecord

public DynamicRecord forceGetRecord(long id)

Specified by:

forceGetRecord in interface RecordStore<DynamicRecord>

forceGetRaw

public DynamicRecord forceGetRaw(long id)

Specified by:

forceGetRaw in interface RecordStore<DynamicRecord>

getRecords

public Collection<DynamicRecord> getRecords(long startBlockId)

rebuildIdGenerator

protected void rebuildIdGenerator()

Rebuilds the internal id generator keeping track of what blocks are free or taken.

Specified by:

rebuildIdGenerator in class CommonAbstractStore

Throws:

IOException - If unable to rebuild the id generator

figureOutHighestIdInUse

protected long figureOutHighestIdInUse()

Specified by:

figureOutHighestIdInUse in class CommonAbstractStore

logIdUsage

public void logIdUsage(StringLogger logger)

Specified by:

logIdUsage in interface Store

toString

public String toString()

Overrides:

toString in class CommonAbstractStore