Apache Derby Database Engine and Embedded JDBC Driver 10.17.1.0 · org.apache.derby.impl.store.raw.xact.TransactionTable

Modifier and Type	Class and Description
pack-priv static interface	TransactionTable.EntryVisitor Interface for visiting entries in the transaction table.

Modifier and Type	Field and Description
private TransactionId	largestUpdateXactId
private final ConcurrentHashMap<TransactionId, TransactionTableEntry>	trans

Access	Constructor and Description
public	TransactionTable() MT - not needed for constructor

Method Summary

Modifier and Type	Method and Description
pack-priv void	add(Xact xact, boolean exclude)
public void	addUpdateTransaction(TransactionId the transaction id tid, RawTransaction the transaction to be added tran, int the transaction status that is stored in the BeginXact log record transactionStatus) Change a transaction to update or add an update transaction to this table.
pack-priv boolean	Returns: true if transaction can be found, false otherwise findAndAssumeTransaction(TransactionId transaction Id id, RawTransaction the transaction that was made to assume the transactionID and all other relevant information stored in the transaction table tran) Find a transaction using the transaction id, and make the passed in transaction assume the identity and properties of that transaction.
public ContextManager	Returns: The ContextManager of the transaction being searched for. findTransactionContextByGlobalId(final GlobalXactId The global transaction we are searching for. global_id) Find a transaction in the table by Global transaction id. This routine use to be only called during offline recovery so performance was not critical.
private TransactionTableEntry	findTransactionEntry(TransactionId id) generic methods called by all clients of transaction table Must be MT -safe
public LogInstant	Returns: the RawTransaction's first log instant MT - safe, caller can be recovery or checkpoint getFirstLogInstant() Get the least recently added (oldest) transaction
public boolean	Returns: true if a candidate transaction has been found. false if no prepared/recovery transactions found in the table. getMostRecentPreparedRecoveredXact(RawTransaction Newly allocated transaction to add to link to a entry. tran) Get the most recent recovered prepared transaction.
public boolean	getMostRecentRollbackFirstTransaction(RawTransaction tran) Get the most recently added transaction that says it needs to be rolled back first (an InternalXact) from the transaction table and make the passed in transaction assume its identity.
public boolean	getMostRecentTransactionForRollback(RawTransaction tran) Get the most recently non-prepared added transaction from the transaction table and make the passed in transaction assume its identity.
public TransactionInfo[]	getTransactionInfo() Get a printable version of the transaction table
public int	getTypeFormatId() Implements org.apache.derby.iapi.services.io.TypedFormat.getTypeFormatId. Return my format identifier.
pack-priv boolean	hasActiveUpdateTransaction() Return true if there is no transaction actively updating the database.
public boolean	hasPreparedRecoveredXact() Is there a prepared transaction that are recovered durring the recovery in the transaction table.
public boolean	hasPreparedXact() Is there a prepared transaction in the transaction table.
private boolean	Returns: `true if there is a prepared transaction and recovered when recovered argument is true` `hasPreparedXact(boolean true to search for transaction that are in prepared during recovery. recovered tranaction. false > to search for just prepared transactons.recovered)Is there a prepared transaction in the transaction table.`
public boolean	hasRollbackFirstTransaction() Is there an active internal transaction in the transaction table.
public TransactionId	largestUpdateXactId() Return the largest update transactionId I have seen so far.
pack-priv void	prepareTransaction(TransactionId the transaction Id id) Change transaction to prepared.
public void	readExternal(ObjectInput the stream to read data from in order to restore the object in) Implements java.io.Externalizable.readExternal. The object implements the readExternal method to restore its contents by calling the methods of DataInput for primitive types and readObject for objects, strings and arrays.
pack-priv boolean	remove(TransactionId id) remove the transaction Id an return false iff the transaction is found in the table and it doesn't need exclusion during quiesce state
pack-priv void	removeUpdateTransaction(TransactionId the transaction Id id) Change update transaction to non-update MT - MT safe, since vector is MT-safe.
public String	toString() Overrides java.lang.Object.toString. Returns a string representation of the object.
pack-priv void	visitEntries(TransactionTable.EntryVisitor the visitor to apply on each transaction table entry visitor) Visit all the entries in the transaction table.
public void	writeExternal(final ObjectOutput the stream to write the object to out) Implements java.io.Externalizable.writeExternal. The object implements the writeExternal method to save its contents by calling the methods of DataOutput for its primitive values or calling the writeObject method of ObjectOutput for objects, strings, and arrays.

Inherited from java.lang.Object:: clone equals finalize getClass hashCode notify notifyAll wait wait wait

largestUpdateXactId	back to summary
private TransactionId largestUpdateXactId

trans	back to summary
private final ConcurrentHashMap<TransactionId, TransactionTableEntry> trans

TransactionTable	back to summary
public TransactionTable() MT - not needed for constructor

Method Detail

add	back to summary
pack-priv void add(Xact xact, boolean exclude)

addUpdateTransaction	back to summary
public void addUpdateTransaction(TransactionId tid, RawTransaction tran, int transactionStatus) Change a transaction to update or add an update transaction to this table. Parameters tid:TransactionId the transaction id tran:RawTransaction the transaction to be added transactionStatus:int the transaction status that is stored in the BeginXact log record

addUpdateTransaction

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public void addUpdateTransaction(TransactionId tid, RawTransaction tran, int transactionStatus)

Change a transaction to update or add an update transaction to this table.

Parameters

tid:TransactionId: the transaction id
tran:RawTransaction: the transaction to be added
transactionStatus:int: the transaction status that is stored in the BeginXact log record

findAndAssumeTransaction	back to summary
pack-priv boolean findAndAssumeTransaction(TransactionId id, RawTransaction tran) Find a transaction using the transaction id, and make the passed in transaction assume the identity and properties of that transaction. MT - unsafe, caller is recovery, which is single threaded. Parameters id:TransactionId transaction Id tran:RawTransaction the transaction that was made to assume the transactionID and all other relevant information stored in the transaction table Returns:boolean true if transaction can be found, false otherwise

findAndAssumeTransaction

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pack-priv boolean findAndAssumeTransaction(TransactionId id, RawTransaction tran)

Find a transaction using the transaction id, and make the passed in transaction assume the identity and properties of that transaction.

MT - unsafe, caller is recovery, which is single threaded.

Parameters

id:TransactionId: transaction Id
tran:RawTransaction: the transaction that was made to assume the transactionID and all other relevant information stored in the transaction table

Returns:boolean

true if transaction can be found, false otherwise

findTransactionContextByGlobalId	back to summary
public ContextManager findTransactionContextByGlobalId(final GlobalXactId global_id) Find a transaction in the table by Global transaction id. This routine use to be only called during offline recovery so performance was not critical. Since that time more calls have been made, including one in startGlobalTransaction() so a linear search may no longer be appropriate. See DERBY-828. Parameters global_id:GlobalXactId The global transaction we are searching for. Returns:ContextManager The ContextManager of the transaction being searched for.

findTransactionContextByGlobalId

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public ContextManager findTransactionContextByGlobalId(final GlobalXactId global_id)

Find a transaction in the table by Global transaction id.

This routine use to be only called during offline recovery so performance was not critical. Since that time more calls have been made, including one in startGlobalTransaction() so a linear search may no longer be appropriate. See DERBY-828.

Parameters

global_id:GlobalXactId: The global transaction we are searching for.

Returns:ContextManager

The ContextManager of the transaction being searched for.

findTransactionEntry	back to summary
private TransactionTableEntry findTransactionEntry(TransactionId id) generic methods called by all clients of transaction table Must be MT -safe

getFirstLogInstant	back to summary
public LogInstant getFirstLogInstant() Get the least recently added (oldest) transaction Returns:LogInstant the RawTransaction's first log instant MT - safe, caller can be recovery or checkpoint

getFirstLogInstant

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public LogInstant getFirstLogInstant()

Get the least recently added (oldest) transaction

Returns:LogInstant

the RawTransaction's first log instant

MT - safe, caller can be recovery or checkpoint

getMostRecentPreparedRecoveredXact	back to summary
public boolean getMostRecentPreparedRecoveredXact(RawTransaction tran) Get the most recent recovered prepared transaction. Get the most recently added transaction that says it is prepared during recovery the transaction table and make the passed in transaction assume its identity. This routine, unlike the redo and rollback getMostRecent() routines expects a brand new transaction to be passed in. If a candidate transaction is found, then upon return the transaction table will be altered such that the old entry no longer exists, and a new entry will exist pointing to the transaction passed in. The new entry will look the same as if the prepared transaction had been created during runtime rather than recovery. Should only be used in recovery handle prepare after undo !!* MT - unsafe, caller is recovery, which is single threaded. Parameters tran:RawTransaction Newly allocated transaction to add to link to a entry. Returns:boolean true if a candidate transaction has been found. false if no prepared/recovery transactions found in the table.

getMostRecentPreparedRecoveredXact

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public boolean getMostRecentPreparedRecoveredXact(RawTransaction tran)

Get the most recent recovered prepared transaction.

Get the most recently added transaction that says it is prepared during recovery the transaction table and make the passed in transaction assume its identity.

This routine, unlike the redo and rollback getMostRecent*() routines expects a brand new transaction to be passed in. If a candidate transaction is found, then upon return the transaction table will be altered such that the old entry no longer exists, and a new entry will exist pointing to the transaction passed in. The new entry will look the same as if the prepared transaction had been created during runtime rather than recovery. Should only be used in recovery handle prepare after undo !!

MT - unsafe, caller is recovery, which is single threaded.

Parameters

tran:RawTransaction: Newly allocated transaction to add to link to a entry.

Returns:boolean

true if a candidate transaction has been found. false if no prepared/recovery transactions found in the table.

getMostRecentRollbackFirstTransaction	back to summary
public boolean getMostRecentRollbackFirstTransaction(RawTransaction tran) Get the most recently added transaction that says it needs to be rolled back first (an InternalXact) from the transaction table and make the passed in transaction assume its identity. Should only be used in recovery undo !! Resolve (sku)I don't think even these internal transactions need to be rolled back in the reverse order, because they are physical in nature. But it won't hurt. MT - unsafe, caller is recovery, which is single threaded.

getMostRecentRollbackFirstTransaction

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public boolean getMostRecentRollbackFirstTransaction(RawTransaction tran)

Get the most recently added transaction that says it needs to be rolled back first (an InternalXact) from the transaction table and make the passed in transaction assume its identity. Should only be used in recovery undo !!

Resolve

(sku)I don't think even these internal transactions need to be rolled back in the reverse order, because they are physical in nature. But it won't hurt.

MT - unsafe, caller is recovery, which is single threaded.

getMostRecentTransactionForRollback	back to summary
public boolean getMostRecentTransactionForRollback(RawTransaction tran) Get the most recently non-prepared added transaction from the transaction table and make the passed in transaction assume its identity. Prepared transactions will not be undone. Resolve (sku) I don't think normal user transactions needs to be rolled back in order, but it won't hurt. Should only be used in recovery undo !! MT - unsafe, caller is recovery, which is single threaded.

getMostRecentTransactionForRollback

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public boolean getMostRecentTransactionForRollback(RawTransaction tran)

Get the most recently non-prepared added transaction from the transaction table and make the passed in transaction assume its identity. Prepared transactions will not be undone.

Resolve

(sku) I don't think normal user transactions needs to be rolled back in order, but it won't hurt. Should only be used in recovery undo !!

MT - unsafe, caller is recovery, which is single threaded.

getTransactionInfo	back to summary
public TransactionInfo[] getTransactionInfo() Get a printable version of the transaction table

getTypeFormatId	back to summary
public int getTypeFormatId() Implements org.apache.derby.iapi.services.io.TypedFormat.getTypeFormatId. Return my format identifier. Returns:int Doc from org.apache.derby.iapi.services.io.TypedFormat.getTypeFormatId. The identifier. (A UUID stuffed in an array of 16 bytes).

getTypeFormatId

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public int getTypeFormatId()

Implements org.apache.derby.iapi.services.io.TypedFormat.getTypeFormatId.

Return my format identifier.

Returns:int

Doc from org.apache.derby.iapi.services.io.TypedFormat.getTypeFormatId.

The identifier. (A UUID stuffed in an array of 16 bytes).

hasActiveUpdateTransaction	back to summary
pack-priv boolean hasActiveUpdateTransaction() Return true if there is no transaction actively updating the database. New transaction may be started or old transaction committed right afterward, the caller of this routine must have other ways to stop transactions from starting or ending. MT - safe

hasActiveUpdateTransaction

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pack-priv boolean hasActiveUpdateTransaction()

Return true if there is no transaction actively updating the database. New transaction may be started or old transaction committed right afterward, the caller of this routine must have other ways to stop transactions from starting or ending.

MT - safe

hasPreparedRecoveredXact	back to summary
public boolean hasPreparedRecoveredXact() Is there a prepared transaction that are recovered durring the recovery in the transaction table. MT - unsafe, caller is recovery, which is single threaded.

hasPreparedRecoveredXact

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public boolean hasPreparedRecoveredXact()

Is there a prepared transaction that are recovered durring the recovery in the transaction table.

MT - unsafe, caller is recovery, which is single threaded.

hasPreparedXact	back to summary
public boolean hasPreparedXact() Is there a prepared transaction in the transaction table. MT - unsafe, called during boot, which is single threaded.

hasPreparedXact

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public boolean hasPreparedXact()

Is there a prepared transaction in the transaction table.

MT - unsafe, called during boot, which is single threaded.

hasPreparedXact back to summary

hasPreparedXact	back to summary
private boolean hasPreparedXact(boolean recovered) Is there a prepared transaction in the transaction table. MT - unsafe, caller is recovery/at boot, which is single threaded. Parameters recovered:boolean `true` to search for transaction that are in prepared during recovery. recovered tranaction. `false > to search for just prepared transactons.` `Returns:boolean` `true if there is a prepared transaction and recovered when recovered argument is true`

private boolean hasPreparedXact(boolean recovered)

Is there a prepared transaction in the transaction table.

MT - unsafe, caller is recovery/at boot, which is single threaded.

Parameters

recovered:boolean: true to search for transaction that are in prepared during recovery. recovered tranaction. false > to search for just prepared transactons.

Returns:boolean

true if there is a prepared transaction and recovered when recovered argument is true

hasRollbackFirstTransaction	back to summary
public boolean hasRollbackFirstTransaction() Is there an active internal transaction in the transaction table. MT - unsafe, caller is recovery, which is single threaded.

hasRollbackFirstTransaction

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public boolean hasRollbackFirstTransaction()

Is there an active internal transaction in the transaction table.

MT - unsafe, caller is recovery, which is single threaded.

largestUpdateXactId	back to summary
public TransactionId largestUpdateXactId() Return the largest update transactionId I have seen so far. MT - unsafe, caller is recovery, which is single threaded.

largestUpdateXactId

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public TransactionId largestUpdateXactId()

Return the largest update transactionId I have seen so far.

MT - unsafe, caller is recovery, which is single threaded.

prepareTransaction	back to summary
pack-priv void prepareTransaction(TransactionId id) Change transaction to prepared. MT - unsafe, caller is recovery, which is single threaded. Parameters id:TransactionId the transaction Id

prepareTransaction

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pack-priv void prepareTransaction(TransactionId id)

Change transaction to prepared.

MT - unsafe, caller is recovery, which is single threaded.

Parameters

id:TransactionId: the transaction Id

readExternal	back to summary
public void readExternal(ObjectInput in) throws IOException, ClassNotFoundException Implements java.io.Externalizable.readExternal. Doc from java.io.Externalizable.readExternal. The object implements the readExternal method to restore its contents by calling the methods of DataInput for primitive types and readObject for objects, strings and arrays. The readExternal method must read the values in the same sequence and with the same types as were written by writeExternal. Parameters in:ObjectInput the stream to read data from in order to restore the object Exceptions IOException: problem reading the transaction table ClassNotFoundException: problem reading the transaction table

readExternal

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public void readExternal(ObjectInput in) throws IOException, ClassNotFoundException

Implements java.io.Externalizable.readExternal.

Doc from java.io.Externalizable.readExternal.

The object implements the readExternal method to restore its contents by calling the methods of DataInput for primitive types and readObject for objects, strings and arrays. The readExternal method must read the values in the same sequence and with the same types as were written by writeExternal.

Parameters

in:ObjectInput: the stream to read data from in order to restore the object

Exceptions

IOException:: problem reading the transaction table
ClassNotFoundException:: problem reading the transaction table

remove	back to summary
pack-priv boolean remove(TransactionId id) remove the transaction Id an return false iff the transaction is found in the table and it doesn't need exclusion during quiesce state

removeUpdateTransaction	back to summary
pack-priv void removeUpdateTransaction(TransactionId id) Change update transaction to non-update MT - MT safe, since vector is MT-safe. Parameters id:TransactionId the transaction Id

removeUpdateTransaction

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pack-priv void removeUpdateTransaction(TransactionId id)

Change update transaction to non-update

MT - MT safe, since vector is MT-safe.

Parameters

id:TransactionId: the transaction Id

toString back to summary

toString	back to summary
public String toString() Overrides java.lang.Object.toString. Doc from java.lang.Object.toString. Returns a string representation of the object. Satisfying this method's contract implies a non-`null` result must be returned. Returns:String a string representation of the object

public String toString()

Overrides java.lang.Object.toString.

Doc from java.lang.Object.toString.

Returns a string representation of the object. Satisfying this method's contract implies a non-null result must be returned.

Returns:String: a string representation of the object

visitEntries back to summary

visitEntries	back to summary
pack-priv void visitEntries(TransactionTable.EntryVisitor visitor) Visit all the entries in the transaction table. MT - MT safe Entries that are added to or removed from the transaction table while it's being traversed, may or may not be visited. All the entries that are present in the map when this method is called, and have not been removed when the method returns, will have been visited exactly once (except if the `visit()` method returns false before all entries have been visited, in which case the traversal of the map will stop earlier). Note however that this method does not guarantee that a single `TransactionTableEntry` is not accessed concurrently by multiple threads. If the visitor accesses some of the entry's mutable state, the caller must ensure that appropriate synchronization protection is in place. For example, if accessing the update state of the entry, the caller must synchronize on "this" (the `TransactionTable` instance). Parameters visitor:TransactionTable.EntryVisitor the visitor to apply on each transaction table entry

pack-priv void visitEntries(TransactionTable.EntryVisitor visitor)

Visit all the entries in the transaction table.

MT - MT safe

Entries that are added to or removed from the transaction table while it's being traversed, may or may not be visited. All the entries that are present in the map when this method is called, and have not been removed when the method returns, will have been visited exactly once (except if the visit() method returns false before all entries have been visited, in which case the traversal of the map will stop earlier).

Note however that this method does not guarantee that a single TransactionTableEntry is not accessed concurrently by multiple threads. If the visitor accesses some of the entry's mutable state, the caller must ensure that appropriate synchronization protection is in place. For example, if accessing the update state of the entry, the caller must synchronize on "this" (the TransactionTable instance).

Parameters

visitor:TransactionTable.EntryVisitor: the visitor to apply on each transaction table entry

writeExternal	back to summary
public void writeExternal(final ObjectOutput out) throws IOException Implements java.io.Externalizable.writeExternal. Doc from java.io.Externalizable.writeExternal. The object implements the writeExternal method to save its contents by calling the methods of DataOutput for its primitive values or calling the writeObject method of ObjectOutput for objects, strings, and arrays. Parameters out:ObjectOutput the stream to write the object to Exceptions IOException: problem reading the transaction table

writeExternal

back to summary

public void writeExternal(final ObjectOutput out) throws IOException

Implements java.io.Externalizable.writeExternal.

Doc from java.io.Externalizable.writeExternal.

The object implements the writeExternal method to save its contents by calling the methods of DataOutput for its primitive values or calling the writeObject method of ObjectOutput for objects, strings, and arrays.

Parameters

out:ObjectOutput: the stream to write the object to

Exceptions

IOException:: problem reading the transaction table

public Class TransactionTable

Nested and Inner Type Summary

Field Summary

Constructor Summary

Method Summary

Field Detail

Constructor Detail

Method Detail

pack-priv Interface TransactionTable.EntryVisitor

Method Summary

Method Detail