org.mapdb

Class StoreWAL

java.lang.Object

org.mapdb.Store

org.mapdb.StoreDirect

org.mapdb.StoreCached

org.mapdb.StoreWAL

All Implemented Interfaces:

Closeable, AutoCloseable, Engine

public class StoreWAL
extends StoreCached

Write-Ahead-Log

Nested Class Summary

Nested classes/interfaces inherited from class org.mapdb.StoreDirect

StoreDirect.Snapshot

Nested classes/interfaces inherited from class org.mapdb.Store

Store.Cache, Store.LongList, Store.LongLongMap, Store.LongObjectMap<V>, Store.LongObjectObjectMap<V1,V2>, Store.LongQueue, Store.MemoryBarrierLessLock, Store.ReadWriteSingleLock

Nested classes/interfaces inherited from interface org.mapdb.Engine

Engine.CloseOnJVMShutdown, Engine.ReadOnly, Engine.ReadOnlyWrapper

Field Summary

Fields

Modifier and Type	Field and Description
protected boolean	$_TEST_HACK_COMPACT_POST_COMMIT_WAIT
protected boolean	$_TEST_HACK_COMPACT_PRE_COMMIT_WAIT
protected Store.LongLongMap[]	committedDataLongs Contains vol modifications from previous committed transactions, which are not yet replayed into vol.
protected Store.LongLongMap[]	committedIndexTable Contains index table modifications from previous committed transactions, which are not yet replayed into vol.
protected Store.LongLongMap	committedPageLongStack Contains modified Long Stack Pages from previous committed transactions, which are not yet replayed into vol.
protected static int	FULL_REPLAY_AFTER_N_TX
protected byte[]	headVolBackup
protected long[]	indexPagesBackup
protected Volume	realVol
protected Store.LongLongMap[]	uncommittedDataLongs Contains vol modifications from current not yet committed transaction.
protected Store.LongLongMap[]	uncommittedIndexTable Contains index table modifications from current not yet committed transaction.
protected WriteAheadLog	wal

Fields inherited from class org.mapdb.StoreCached

flushInThread, LONG_STACK_PAGE_TOMBSTONE, TOMBSTONE2, uncommittedStackPages, writeCache, writeQueueSize, writeQueueSizePerSegment

Fields inherited from class org.mapdb.StoreDirect

EMPTY_LONGS, executor, FREE_RECID_STACK, freeSize, HEAD_END, HEADER, headVol, INDEX_VAL_SIZE, indexPages, INITCRC_INDEX_PAGE, LAST_PHYS_ALLOCATED_DATA_OFFSET, LONG_STACK_MAX_SIZE, LONG_STACK_MIN_SIZE, LONG_STACK_PREF_SIZE, MARCHIVE, MAX_REC_SIZE, MAX_RECID_OFFSET, MLINKED, MOFFSET, MPARITY, MUNUSED, PAGE_MASK, PAGE_MASK_INVERSE, PAGE_SIZE, recidReuseDisable, sizeIncrement, sliceShift, SLOTS_COUNT, snapshots, startSize, STORE_SIZE, STORE_VERSION, UNUSED1, UNUSED2, UNUSED3, UNUSED4, UNUSED5, vol

Fields inherited from class org.mapdb.Store

caches, checksum, closed, commitLock, compress, deserializeExtra, encrypt, encryptionXTEA, FEAT_COMP_LZF, FEAT_CRC, FEAT_ENC_XTEA, fileLockDisable, fileLockHeartbeat, fileName, HEAD_CHECKSUM, HEAD_FEATURES, LOCKING_STRATEGY_NOLOCK, LOCKING_STRATEGY_READWRITELOCK, LOCKING_STRATEGY_WRITELOCK, lockMask, locks, lockScale, LOG, LZF, metricsDataRead, metricsDataWrite, metricsRecordRead, metricsRecordWrite, NOLOCK, readonly, recycledDataOut, snapshotEnable, structuralLock, volumeFactory

Fields inherited from interface org.mapdb.Engine

CLOSED_ENGINE, RECID_CLASS_CATALOG, RECID_FIRST, RECID_LAST_RESERVED, RECID_NAME_CATALOG, RECID_RECORD_CHECK

Constructor Summary

Constructors

Constructor and Description
StoreWAL(String fileName)
StoreWAL(String fileName, Volume.VolumeFactory volumeFactory, Store.Cache cache, int lockScale, int lockingStrategy, boolean checksum, boolean compress, byte[] password, boolean readonly, boolean snapshotEnable, boolean fileLockDisable, DataIO.HeartbeatFileLock fileLockHeartbeat, ScheduledExecutorService executor, long startSize, long sizeIncrement, boolean recidReuseDisable, long executorScheduledRate, int writeQueueSize)

Method Summary

Methods

Modifier and Type	Method and Description
boolean	canRollback()
void	close() Close store/cache.
void	commit() Makes all changes made since the previous commit/rollback permanent.
void	compact()
protected void	freeDataPut(int segment, long offset, int size)
protected <A> A	get2(long recid, Serializer<A> serializer)
protected boolean	hasUncommitedData() return true if there are uncommited data in current transaction, otherwise false
protected void	indexLongPut(long offset, long val)
protected long	indexValGet(long recid)
protected long	indexValGetRaw(long recid)
protected void	indexValPut(long recid, int size, long offset, boolean linked, boolean unused)
protected void	initCreate()
protected void	initFailedCloseFiles()
protected void	initHeadVol()
void	initOpen()
protected void	initOpenPost()
protected byte[]	loadLongStackPage(long pageOffset, boolean willBeModified)
protected long[]	offsetsGet(int segment, long indexVal) return positions of (possibly) linked record
protected long	pageAllocate()
protected void	putDataSingleWithLink(int segment, long offset, long link, byte[] buf, int bufPos, int size)
protected void	putDataSingleWithoutLink(int segment, long offset, byte[] buf, int bufPos, int size)
protected void	replaySoft()
void	rollback() Undoes all changes made in the current transaction.
protected DataInput	walGetData(long offset, int segment)

Methods inherited from class org.mapdb.StoreCached

assertLongStackPage, assertNoOverlaps, compareAndSwap, delete2, flush, flushWriteCache, flushWriteCacheSegment, longStackCount, longStackNewPage, longStackPut, longStackTake, put, update

Methods inherited from class org.mapdb.StoreDirect

backup, backupRestore, clearCache, closeFilesIgnoreException, compactIndexPage, compactIndexPages, compactOldFilesExists, composeIndexVal, fileLoad, freeDataPut, freeDataTake, freeDataTakeSingle, freeRecidTake, freeSizeIncrement, getCurrSize, getFreeSize, getFromOffset, headChecksum, init, lastAllocatedDataGet, lastAllocatedDataSet, longStackMasterLinkOffset, maxRecidGet, maxRecidSet, offsetsTotalSize, offsetsVerify, pageIndexEnsurePageForRecidAllocated, pageIndexExtend, preallocate, putData, recidToOffset, recidTooLarge, round16Up, snapshot, snapshotCloseAllOnCompact, storeSizeGet, storeSizeSet, update2

Methods inherited from class org.mapdb.Store

assertReadLocked, assertWriteLocked, canSnapshot, checkFeaturesBitmap, delete, deserialize, forDB, forEngine, get, getWrappedEngine, isClosed, isReadOnly, lockPos, longParityGet, longParitySet, makeFeaturesBitmap, metricsCollect, newDataOut2, serialize

Methods inherited from class java.lang.Object

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

Field Detail

FULL_REPLAY_AFTER_N_TX

protected static final int FULL_REPLAY_AFTER_N_TX

See Also:

Constant Field Values

committedIndexTable

protected final Store.LongLongMap[] committedIndexTable

Contains index table modifications from previous committed transactions, which are not yet replayed into vol. Key is offset in vol, value is new index table value

uncommittedIndexTable

protected final Store.LongLongMap[] uncommittedIndexTable

Contains index table modifications from current not yet committed transaction. Key is offset in vol, value is new index table value

committedDataLongs

protected final Store.LongLongMap[] committedDataLongs

Contains vol modifications from previous committed transactions, which are not yet replayed into vol. Key is offset in vol, value is walPointer returned by WriteAheadLog.walPutByteArray(long, byte[], int, int)

uncommittedDataLongs

protected final Store.LongLongMap[] uncommittedDataLongs

Contains vol modifications from current not yet committed transaction. Key is offset in vol, value is walPointer returned by WriteAheadLog.walPutByteArray(long, byte[], int, int)

committedPageLongStack

protected final Store.LongLongMap committedPageLongStack

Contains modified Long Stack Pages from previous committed transactions, which are not yet replayed into vol. Key is offset in vol, value is walPointer returned by WriteAheadLog.walPutByteArray(long, byte[], int, int)

headVolBackup

protected byte[] headVolBackup

indexPagesBackup

protected long[] indexPagesBackup

realVol

protected Volume realVol

$_TEST_HACK_COMPACT_PRE_COMMIT_WAIT

protected volatile boolean $_TEST_HACK_COMPACT_PRE_COMMIT_WAIT

$_TEST_HACK_COMPACT_POST_COMMIT_WAIT

protected volatile boolean $_TEST_HACK_COMPACT_POST_COMMIT_WAIT

wal

protected final WriteAheadLog wal

Constructor Detail

StoreWAL

public StoreWAL(String fileName)

StoreWAL

public StoreWAL(String fileName,
        Volume.VolumeFactory volumeFactory,
        Store.Cache cache,
        int lockScale,
        int lockingStrategy,
        boolean checksum,
        boolean compress,
        byte[] password,
        boolean readonly,
        boolean snapshotEnable,
        boolean fileLockDisable,
        DataIO.HeartbeatFileLock fileLockHeartbeat,
        ScheduledExecutorService executor,
        long startSize,
        long sizeIncrement,
        boolean recidReuseDisable,
        long executorScheduledRate,
        int writeQueueSize)

Method Detail

initCreate

protected void initCreate()

Overrides:

initCreate in class StoreDirect

initOpen

public void initOpen()

Overrides:

initOpen in class StoreDirect

initFailedCloseFiles

protected void initFailedCloseFiles()

Overrides:

initFailedCloseFiles in class StoreDirect

initOpenPost

protected void initOpenPost()

initHeadVol

protected void initHeadVol()

Overrides:

initHeadVol in class StoreCached

putDataSingleWithLink

protected void putDataSingleWithLink(int segment,
                         long offset,
                         long link,
                         byte[] buf,
                         int bufPos,
                         int size)

Overrides:

putDataSingleWithLink in class StoreDirect

putDataSingleWithoutLink

protected void putDataSingleWithoutLink(int segment,
                            long offset,
                            byte[] buf,
                            int bufPos,
                            int size)

Overrides:

putDataSingleWithoutLink in class StoreDirect

walGetData

protected DataInput walGetData(long offset,
                   int segment)

indexValGet

protected long indexValGet(long recid)

Overrides:

indexValGet in class StoreDirect

indexValGetRaw

protected long indexValGetRaw(long recid)

Overrides:

indexValGetRaw in class StoreDirect

indexValPut

protected void indexValPut(long recid,
               int size,
               long offset,
               boolean linked,
               boolean unused)

Overrides:

indexValPut in class StoreDirect

indexLongPut

protected void indexLongPut(long offset,
                long val)

Overrides:

indexLongPut in class StoreDirect

pageAllocate

protected long pageAllocate()

Overrides:

pageAllocate in class StoreDirect

loadLongStackPage

protected byte[] loadLongStackPage(long pageOffset,
                       boolean willBeModified)

Overrides:

loadLongStackPage in class StoreCached

offsetsGet

protected long[] offsetsGet(int segment,
                long indexVal)

return positions of (possibly) linked record

Overrides:

offsetsGet in class StoreDirect

get2

protected <A> A get2(long recid,
         Serializer<A> serializer)

Overrides:

get2 in class StoreCached

rollback

public void rollback()
              throws UnsupportedOperationException

Description copied from interface: Engine

Undoes all changes made in the current transaction. If transactions are disabled it throws UnsupportedOperationException.

Specified by:

rollback in interface Engine

Overrides:

rollback in class StoreDirect

Throws:

UnsupportedOperationException - if transactions are disabled

commit

public void commit()

Description copied from interface: Engine

Makes all changes made since the previous commit/rollback permanent. In transactional mode (on by default) it means creating journal file and replaying it to storage. In other modes it may flush disk caches or do nothing at all (check your config options)

Specified by:

commit in interface Engine

Overrides:

commit in class StoreDirect

replaySoft

protected void replaySoft()

canRollback

public boolean canRollback()

Specified by:

canRollback in interface Engine

Overrides:

canRollback in class StoreDirect

Returns:

true if engine supports rollback

close

public void close()

Description copied from interface: Engine

Close store/cache. This method must be called before JVM exits to flush all caches and prevent store corruption. Also it releases resources used by MapDB (disk, memory..).

Engine can no longer be used after this method was called. If Engine is used after closing, it may throw any exception including NullPointerException

There is an configuration option DBMaker.Maker.closeOnJvmShutdown() which uses shutdown hook to automatically close Engine when JVM shutdowns.

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Engine

Overrides:

close in class StoreDirect

compact

public void compact()

Specified by:

compact in interface Engine

Overrides:

compact in class StoreDirect

hasUncommitedData

protected boolean hasUncommitedData()

return true if there are uncommited data in current transaction, otherwise false

freeDataPut

protected void freeDataPut(int segment,
               long offset,
               int size)

Overrides:

freeDataPut in class StoreDirect