Package com.arcadedb.database

Class TransactionContext

java.lang.Object

com.arcadedb.database.TransactionContext

All Implemented Interfaces:

Transaction

public class TransactionContext
extends Object
implements Transaction

Manage the transaction context. When the transaction begins, the modifiedPages map is initialized. This allows to always delegate to the transaction context, even if there is no active transaction by ignoring tx data.
At commit time, the files are locked in order (to avoid deadlocks) and to allow parallel commit on different files.
Format of WAL:
txId:long|pages:int|<segmentSize:int|fileId:int|pageNumber:long|pageModifiedFrom:int|pageModifiedTo:int|<prevContent><newContent>segmentSize:int>MagicNumber:long

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	TransactionContext.STATUS
static class	TransactionContext.TransactionPhase1

Constructor Summary

Constructors

Constructor	Description
TransactionContext(DatabaseInternal database)

Method Summary

Modifier and Type	Method	Description
void	addIndexOperation(IndexInternal index, boolean addOperation, Object[] keys, RID rid)
MutablePage	addPage(PageId pageId, int pageSize)
void	addUpdatedRecord(Record record)
void	assureIsActive()
void	begin(Database.TRANSACTION_ISOLATION_LEVEL isolationLevel)
Binary	commit()
TransactionContext.TransactionPhase1	commit1stPhase(boolean isLeader)	Locks the files in order, then checks all the pre-conditions.
void	commit2ndPhase(TransactionContext.TransactionPhase1 changes)
void	commitFromReplica(WALFile.WALTransaction buffer, Map<String,TreeMap<TransactionIndexContext.ComparableKey,Map<TransactionIndexContext.IndexKey,TransactionIndexContext.IndexKey>>> keysTx, Map<Integer,Integer> bucketRecordDelta)	Executes 1st phase from a replica.
Map<Integer,Integer>	getBucketRecordDelta()
long	getBucketRecordDelta(int bucketId)	Returns the delta of records considering the pending changes in transaction.
DatabaseInternal	getDatabase()
long	getFileSize(int fileId)
TransactionIndexContext	getIndexChanges()
int	getModifiedPages()
BasePage	getPage(PageId pageId, int size)	Looks for the page in the TX context first, then delegates to the database.
Integer	getPageCounter(int indexFileId)
MutablePage	getPageToModify(BasePage page)	Puts the page in the TX modified pages.
MutablePage	getPageToModify(PageId pageId, int pageSize, boolean isNew)	If the page is not already in transaction tx, loads from the database and clone it locally.
Record	getRecordFromCache(RID rid)
Map<String,Object>	getStats()
TransactionContext.STATUS	getStatus()
boolean	hasPageForRecord(PageId pageId)	Used to determine if a page has been already loaded.
boolean	isActive()
boolean	isAsyncFlush()
void	kill()	Test only API.
void	removeImmutableRecordsOfSamePage(RID rid)
void	removePagesOfFile(int fileId)
void	removeRecordFromCache(RID rid)
void	reset()
void	rollback()
void	setAsyncFlush(boolean value)
void	setStatus(TransactionContext.STATUS status)
void	setUseWAL(boolean useWAL)
void	setWALFlush(WALFile.FLUSH_TYPE flush)
void	updateBucketRecordDelta(int bucketId, int delta)	Updates the record counter for buckets.
void	updateRecordInCache(Record record)

Methods inherited from class java.lang.Object

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

Constructor Detail

TransactionContext

public TransactionContext(DatabaseInternal database)

Method Detail

begin

public void begin(Database.TRANSACTION_ISOLATION_LEVEL isolationLevel)

Specified by:

begin in interface Transaction

commit

public Binary commit()

Specified by:

commit in interface Transaction

getRecordFromCache

public Record getRecordFromCache(RID rid)

updateRecordInCache

public void updateRecordInCache(Record record)

removeImmutableRecordsOfSamePage

public void removeImmutableRecordsOfSamePage(RID rid)

removeRecordFromCache

public void removeRecordFromCache(RID rid)

getDatabase

public DatabaseInternal getDatabase()

setUseWAL

public void setUseWAL(boolean useWAL)

Specified by:

setUseWAL in interface Transaction

setWALFlush

public void setWALFlush(WALFile.FLUSH_TYPE flush)

Specified by:

setWALFlush in interface Transaction

rollback

public void rollback()

Specified by:

rollback in interface Transaction

assureIsActive

public void assureIsActive()

addUpdatedRecord

public void addUpdatedRecord(Record record)
                      throws IOException

Throws:

IOException

hasPageForRecord

public boolean hasPageForRecord(PageId pageId)

Used to determine if a page has been already loaded. This is important for isolation.

getPage

public BasePage getPage(PageId pageId,
                        int size)
                 throws IOException

Looks for the page in the TX context first, then delegates to the database.

Throws:

IOException

getPageToModify

public MutablePage getPageToModify(PageId pageId,
                                   int pageSize,
                                   boolean isNew)
                            throws IOException

If the page is not already in transaction tx, loads from the database and clone it locally.

Throws:

IOException

getPageToModify

public MutablePage getPageToModify(BasePage page)
                            throws IOException

Puts the page in the TX modified pages.

Throws:

IOException

addPage

public MutablePage addPage(PageId pageId,
                           int pageSize)

getFileSize

public long getFileSize(int fileId)
                 throws IOException

Throws:

IOException

getPageCounter

public Integer getPageCounter(int indexFileId)

isActive

public boolean isActive()

Specified by:

isActive in interface Transaction

getStats

public Map<String,Object> getStats()

getModifiedPages

public int getModifiedPages()

kill

public void kill()

Test only API.

getBucketRecordDelta

public Map<Integer,Integer> getBucketRecordDelta()

getBucketRecordDelta

public long getBucketRecordDelta(int bucketId)

Returns the delta of records considering the pending changes in transaction.

updateBucketRecordDelta

public void updateBucketRecordDelta(int bucketId,
                                    int delta)

Updates the record counter for buckets. At transaction commit, the delta is updated into the schema.

commitFromReplica

public void commitFromReplica(WALFile.WALTransaction buffer,
                              Map<String,TreeMap<TransactionIndexContext.ComparableKey,Map<TransactionIndexContext.IndexKey,TransactionIndexContext.IndexKey>>> keysTx,
                              Map<Integer,Integer> bucketRecordDelta)
                       throws TransactionException

Executes 1st phase from a replica.

Throws:

TransactionException

commit1stPhase

public TransactionContext.TransactionPhase1 commit1stPhase(boolean isLeader)

Locks the files in order, then checks all the pre-conditions.

commit2ndPhase

public void commit2ndPhase(TransactionContext.TransactionPhase1 changes)

addIndexOperation

public void addIndexOperation(IndexInternal index,
                              boolean addOperation,
                              Object[] keys,
                              RID rid)

isAsyncFlush

public boolean isAsyncFlush()

Specified by:

isAsyncFlush in interface Transaction

setAsyncFlush

public void setAsyncFlush(boolean value)

Specified by:

setAsyncFlush in interface Transaction

reset

public void reset()

removePagesOfFile

public void removePagesOfFile(int fileId)

getIndexChanges

public TransactionIndexContext getIndexChanges()

getStatus

public TransactionContext.STATUS getStatus()

setStatus

public void setStatus(TransactionContext.STATUS status)