H2 Database Engine 2.3.232 · org.h2.mvstore.tx.Transaction

Field Summary

Modifier and Type	Field and Description
private Object	blockingKey Key in blockingMap on which this transaction is blocked.
private String	blockingMapName Map on which this transaction is blocked.
private volatile Transaction	blockingTransaction Blocking transaction, if any
pack-priv final IsolationLevel	isolationLevel The current isolation level.
pack-priv final TransactionStore.RollbackListener	listener Listener for this transaction's rollback changes.
pack-priv static final int	LOG_ID_BITS How many bits of the "operation id" we store in the transaction belong to the log id (the rest belong to the transaction id).
private static final int	LOG_ID_BITS1
private static final long	LOG_ID_LIMIT
private static final long	LOG_ID_MASK
private String	name Transaction name.
private volatile boolean	notificationRequested Whether other transaction(s) are waiting for this to close.
private final int	ownerId Identification of the owner of this transaction, usually the owner is a database session.
pack-priv final long	sequenceNum This is really a transaction identity, because it's not re-used.
private static final int	STATUS_BITS
public static final int	STATUS_CLOSED The status of a closed transaction (committed or rolled back).
public static final int	STATUS_COMMITTED The status of a transaction that has been logically committed or rather marked as committed, because it might be still listed among prepared, if it was prepared for commit.
private static final int	STATUS_MASK
private static final String[]	STATUS_NAMES
public static final int	STATUS_OPEN The status of an open transaction.
public static final int	STATUS_PREPARED The status of a prepared transaction.
private static final int	STATUS_ROLLED_BACK The status of a transaction that has been rolled back completely, but undo operations are not finished yet.
private static final int	STATUS_ROLLING_BACK The status of a transaction that currently in a process of rolling back to a savepoint.
private final AtomicLong	statusAndLogId
pack-priv final TransactionStore	store The transaction store.
pack-priv int	timeoutMillis How long to wait for blocking transaction to commit or rollback.
pack-priv final int	transactionId The transaction id. More appropriate name for this field would be "slotId"
private final Map<Integer, TransactionMap<?, ?>>	transactionMaps Map of transactional maps for this transaction
private MVStore.TxCounter	txCounter Reference to a counter for an earliest store version used by this transaction.
private RootReference<Long, Record<?, ?>>[]	undoLogRootReferences RootReferences for undo log snapshots
pack-priv boolean	wasStored Indicates whether this transaction was stored in preparedTransactions map

Constructor Summary

Access	Constructor and Description
pack-priv	Transaction(TransactionStore store, int transactionId, long sequenceNum, int status, String name, long logId, int timeoutMillis, int ownerId, IsolationLevel isolationLevel, TransactionStore.RollbackListener listener)

Method Summary

Modifier and Type	Method and Description
public boolean	Returns: true if isolation level is READ_COMMITTED or READ_UNCOMMITTED allowNonRepeatableRead() Whether this transaction has isolation level READ_COMMITTED or below.
private void	checkNotClosed() Check whether this transaction is open or prepared.
private void	checkOpen(int status) Check whether this transaction is open.
pack-priv void	closeIt() Transition this transaction into a closed state.
public void	commit() Commit the transaction.
private static long	composeState(int status, long logId, boolean hasRollback)
public int	getBlockerId()
public Iterator<TransactionStore.Change>	Returns: the changes getChanges(long the savepoint id, 0 meaning the beginning of the transaction savepointId) Get the list of changes, starting with the latest change, up to the given savepoint (in reverse order than they occurred).
public int	getId()
public IsolationLevel	Returns: the isolation level of this transaction getIsolationLevel() Returns the isolation level of this transaction.
private long	getLogId()
private static long	getLogId(long state)
public String	getName()
public long	getSequenceNum()
public int	getStatus()
private static int	getStatus(long state)
private static String	getStatusName(int status)
pack-priv RootReference<Long, Record<?, ?>>[]	getUndoLogRootReferences()
public boolean	Returns: true if there are changes to commit, false otherwise hasChanges() Determine if any database changes were made as part of this transaction.
private static boolean	hasChanges(long state)
private static boolean	hasRollback(long state)
public boolean	Returns: whether statement dependencies are currently set hasStatementDependencies() Returns whether statement dependencies are currently set.
private static boolean	isActive(int status)
private boolean	isDeadlocked(Transaction toWaitFor)
pack-priv boolean	isReadCommitted()
pack-priv long	Returns: key for the newly added undo log entry log(Record<?, ?> to append logRecord) Add a log entry.
pack-priv void	logUndo() Remove the last log entry.
public void	markStatementEnd() Mark an exit from SQL statement execution within this transaction.
public void	markStatementStart(HashSet<MVMap<Object, VersionedValue<Object>>> set of maps used by transaction or statement is about to be executed maps) Mark an entry into a new SQL statement execution within this transaction.
private void	markTransactionEnd()
private void	notifyAllWaitingTransactions()
public < the key type K, the value type V> TransactionMap<K, V>	Returns: the transaction map openMap(String the name of the map name) Open a data map.
public < the key type K, the value type V> TransactionMap<K, V>	Returns: the transaction map openMap(String the name of the map name, DataType<K> the key data type keyType, DataType<V> the value data type valueType) Open the map to store the data.
public < the key type K, the value type V> TransactionMap<K, V>	Returns: the transactional map openMapX(MVMap<K, VersionedValue<V>> the base map map) Open the transactional version of the given map.
public void	prepare() Prepare the transaction.
private void	releaseSnapshot()
public < the key type K, the value type V> void	removeMap(TransactionMap<K, V> the map map) Remove the map.
public void	rollback() Roll the transaction back.
public void	rollbackToSavepoint(long the savepoint id savepointId) Roll back to the given savepoint.
public void	setName(String name)
public long	Returns: the savepoint id setSavepoint() Create a new savepoint.
private long	Returns: transaction state as it was before status change setStatus(int to be set status) Changes transaction status to a specified value
public void	setTimeoutMillis(int the new lock timeout in milliseconds timeoutMillis) Sets the new lock timeout.
private String	stateToString()
private static String	stateToString(long state)
public String	toString() Overrides java.lang.Object.toString. Returns a string representation of the object.
private void	tryThrowDeadLockException(boolean throwIt)
public boolean	Returns: true if other transaction was closed and this one can proceed, false if timed out waitFor(Transaction transaction to wait for toWaitFor, String name of the map containing blocking entry mapName, Object of the blocking entry key, int timeout in milliseconds, `-1` for default timeoutMillis) Make this transaction to wait for the specified transaction to be closed, because both of them try to modify the same map entry.
private synchronized boolean	waitForThisToEnd(int millis, Transaction waiter)

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

Field Detail

blockingKey	back to summary
private Object blockingKey Key in blockingMap on which this transaction is blocked.

blockingMapName	back to summary
private String blockingMapName Map on which this transaction is blocked.

blockingTransaction	back to summary
private volatile Transaction blockingTransaction Blocking transaction, if any

isolationLevel	back to summary
pack-priv final IsolationLevel isolationLevel The current isolation level.

listener	back to summary
pack-priv final TransactionStore.RollbackListener listener Listener for this transaction's rollback changes.

LOG_ID_BITS	back to summary
pack-priv static final int LOG_ID_BITS How many bits of the "operation id" we store in the transaction belong to the log id (the rest belong to the transaction id).

LOG_ID_BITS1	back to summary
private static final int LOG_ID_BITS1

LOG_ID_LIMIT	back to summary
private static final long LOG_ID_LIMIT

LOG_ID_MASK	back to summary
private static final long LOG_ID_MASK

name	back to summary
private String name Transaction name.

notificationRequested	back to summary
private volatile boolean notificationRequested Whether other transaction(s) are waiting for this to close.

ownerId	back to summary
private final int ownerId Identification of the owner of this transaction, usually the owner is a database session.

sequenceNum	back to summary
pack-priv final long sequenceNum This is really a transaction identity, because it's not re-used.

STATUS_BITS	back to summary
private static final int STATUS_BITS

STATUS_CLOSED	back to summary
public static final int STATUS_CLOSED The status of a closed transaction (committed or rolled back).

STATUS_COMMITTED	back to summary
public static final int STATUS_COMMITTED The status of a transaction that has been logically committed or rather marked as committed, because it might be still listed among prepared, if it was prepared for commit. Undo log entries might still exists for it and not all of it's changes within map's are re-written as committed yet. Nevertheless, those changes should be already viewed by other transactions as committed. This transaction's id can not be re-used until all of the above is completed and transaction is closed. A transactions can be observed in this state when the store was closed while the transaction was not closed yet. When opening a store, such transactions will automatically be processed and closed as committed.

STATUS_COMMITTED

back to summary

public static final int STATUS_COMMITTED

The status of a transaction that has been logically committed or rather marked as committed, because it might be still listed among prepared, if it was prepared for commit. Undo log entries might still exists for it and not all of it's changes within map's are re-written as committed yet. Nevertheless, those changes should be already viewed by other transactions as committed. This transaction's id can not be re-used until all of the above is completed and transaction is closed. A transactions can be observed in this state when the store was closed while the transaction was not closed yet. When opening a store, such transactions will automatically be processed and closed as committed.

STATUS_MASK	back to summary
private static final int STATUS_MASK

STATUS_NAMES	back to summary
private static final String[] STATUS_NAMES

STATUS_OPEN	back to summary
public static final int STATUS_OPEN The status of an open transaction.

STATUS_PREPARED	back to summary
public static final int STATUS_PREPARED The status of a prepared transaction.

STATUS_ROLLED_BACK	back to summary
private static final int STATUS_ROLLED_BACK The status of a transaction that has been rolled back completely, but undo operations are not finished yet.

STATUS_ROLLING_BACK	back to summary
private static final int STATUS_ROLLING_BACK The status of a transaction that currently in a process of rolling back to a savepoint.

statusAndLogId	back to summary
private final AtomicLong statusAndLogId

store	back to summary
pack-priv final TransactionStore store The transaction store.

timeoutMillis	back to summary
pack-priv int timeoutMillis How long to wait for blocking transaction to commit or rollback.

transactionId	back to summary
pack-priv final int transactionId The transaction id. More appropriate name for this field would be "slotId"

transactionMaps	back to summary
private final Map<Integer, TransactionMap<?, ?>> transactionMaps Map of transactional maps for this transaction

txCounter	back to summary
private MVStore.TxCounter txCounter Reference to a counter for an earliest store version used by this transaction. Referenced version and all newer ones can not be discarded at least until this transaction ends.

undoLogRootReferences	back to summary
private RootReference<Long, Record<?, ?>>[] undoLogRootReferences RootReferences for undo log snapshots

wasStored	back to summary
pack-priv boolean wasStored Indicates whether this transaction was stored in preparedTransactions map

Constructor Detail

Transaction	back to summary
pack-priv Transaction(TransactionStore store, int transactionId, long sequenceNum, int status, String name, long logId, int timeoutMillis, int ownerId, IsolationLevel isolationLevel, TransactionStore.RollbackListener listener)

Method Detail

allowNonRepeatableRead	back to summary
public boolean allowNonRepeatableRead() Whether this transaction has isolation level READ_COMMITTED or below. Returns:boolean true if isolation level is READ_COMMITTED or READ_UNCOMMITTED

allowNonRepeatableRead

back to summary

public boolean allowNonRepeatableRead()

Whether this transaction has isolation level READ_COMMITTED or below.

Returns:boolean: true if isolation level is READ_COMMITTED or READ_UNCOMMITTED

checkNotClosed	back to summary
private void checkNotClosed() Check whether this transaction is open or prepared.

checkOpen	back to summary
private void checkOpen(int status) Check whether this transaction is open.

closeIt	back to summary
pack-priv void closeIt() Transition this transaction into a closed state.

commit	back to summary
public void commit() Commit the transaction. Afterwards, this transaction is closed.

composeState	back to summary
private static long composeState(int status, long logId, boolean hasRollback)

getBlockerId	back to summary
public int getBlockerId()

getChanges	back to summary
public Iterator<TransactionStore.Change> getChanges(long savepointId) Get the list of changes, starting with the latest change, up to the given savepoint (in reverse order than they occurred). The value of the change is the value before the change was applied. Parameters savepointId:long the savepoint id, 0 meaning the beginning of the transaction Returns:Iterator<TransactionStore.Change> the changes

getChanges

back to summary

public Iterator<TransactionStore.Change> getChanges(long savepointId)

Get the list of changes, starting with the latest change, up to the given savepoint (in reverse order than they occurred). The value of the change is the value before the change was applied.

Parameters

savepointId:long: the savepoint id, 0 meaning the beginning of the transaction

Returns:Iterator<TransactionStore.Change>

the changes

getId	back to summary
public int getId()

getIsolationLevel	back to summary
public IsolationLevel getIsolationLevel() Returns the isolation level of this transaction. Returns:IsolationLevel the isolation level of this transaction

getIsolationLevel

back to summary

public IsolationLevel getIsolationLevel()

Returns the isolation level of this transaction.

Returns:IsolationLevel: the isolation level of this transaction

getLogId	back to summary
private long getLogId()

getLogId	back to summary
private static long getLogId(long state)

getName	back to summary
public String getName()

getSequenceNum	back to summary
public long getSequenceNum()

getStatus	back to summary
public int getStatus()

getStatus	back to summary
private static int getStatus(long state)

getStatusName	back to summary
private static String getStatusName(int status)

getUndoLogRootReferences	back to summary
pack-priv RootReference<Long, Record<?, ?>>[] getUndoLogRootReferences()

hasChanges

back to summary

public boolean hasChanges()

Determine if any database changes were made as part of this transaction.

Returns:boolean: true if there are changes to commit, false otherwise

hasChanges	back to summary
private static boolean hasChanges(long state)

hasRollback	back to summary
private static boolean hasRollback(long state)

hasStatementDependencies

back to summary

public boolean hasStatementDependencies()

Returns whether statement dependencies are currently set.

Returns:boolean: whether statement dependencies are currently set

isActive	back to summary
private static boolean isActive(int status)

isDeadlocked	back to summary
private boolean isDeadlocked(Transaction toWaitFor)

isReadCommitted	back to summary
pack-priv boolean isReadCommitted()

log

back to summary

pack-priv long log(Record<?, ?> logRecord)

Add a log entry.

Parameters

logRecord:Record<?, ?>: to append

Returns:long

key for the newly added undo log entry

logUndo	back to summary
pack-priv void logUndo() Remove the last log entry.

markStatementEnd	back to summary
public void markStatementEnd() Mark an exit from SQL statement execution within this transaction.

markStatementStart

back to summary

public void markStatementStart(HashSet<MVMap<Object, VersionedValue<Object>>> maps)

Mark an entry into a new SQL statement execution within this transaction.

Parameters

maps:HashSet<MVMap<Object, VersionedValue<Object>>>: set of maps used by transaction or statement is about to be executed

Annotations

@SuppressWarnings:unchecked, rawtypes

markTransactionEnd	back to summary
private void markTransactionEnd()

notifyAllWaitingTransactions	back to summary
private void notifyAllWaitingTransactions()

openMap

back to summary

public <K, V> TransactionMap<K, V> openMap(String name)

Open a data map.

Parameters

<K>: the key type
<V>: the value type
name:String: the name of the map

Returns:TransactionMap<K, V>

the transaction map

openMap

back to summary

public <K, V> TransactionMap<K, V> openMap(String name, DataType<K> keyType, DataType<V> valueType)

Open the map to store the data.

Parameters

<K>: the key type
<V>: the value type
name:String: the name of the map
keyType:DataType<K>: the key data type
valueType:DataType<V>: the value data type

Returns:TransactionMap<K, V>

the transaction map

openMapX

back to summary

public <K, V> TransactionMap<K, V> openMapX(MVMap<K, VersionedValue<V>> map)

Open the transactional version of the given map.

Parameters

<K>: the key type
<V>: the value type
map:MVMap<K, VersionedValue<V>>: the base map

Returns:TransactionMap<K, V>

the transactional map

Annotations

@SuppressWarnings:unchecked

prepare	back to summary
public void prepare() Prepare the transaction. Afterwards, the transaction can only be committed or completely rolled back.

releaseSnapshot	back to summary
private void releaseSnapshot()

removeMap

back to summary

public <K, V> void removeMap(TransactionMap<K, V> map)

Remove the map.

Parameters

<K>: the key type
<V>: the value type
map:TransactionMap<K, V>: the map

rollback	back to summary
public void rollback() Roll the transaction back. Afterwards, this transaction is closed.

rollbackToSavepoint

back to summary

public void rollbackToSavepoint(long savepointId)

Roll back to the given savepoint. This is only allowed if the transaction is open.

Parameters

savepointId:long: the savepoint id

setName	back to summary
public void setName(String name)

setSavepoint

back to summary

public long setSavepoint()

Create a new savepoint.

Returns:long: the savepoint id

setStatus

back to summary

private long setStatus(int status)

Changes transaction status to a specified value

Parameters

status:int: to be set

Returns:long

transaction state as it was before status change

setTimeoutMillis

back to summary

public void setTimeoutMillis(int timeoutMillis)

Sets the new lock timeout.

Parameters

timeoutMillis:int: the new lock timeout in milliseconds

stateToString	back to summary
private String stateToString()

stateToString	back to summary
private static String stateToString(long state)

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

Annotations

@Override

tryThrowDeadLockException	back to summary
private void tryThrowDeadLockException(boolean throwIt)

waitFor back to summary

public boolean waitFor(Transaction toWaitFor, String mapName, Object key, int timeoutMillis)

Make this transaction to wait for the specified transaction to be closed, because both of them try to modify the same map entry.

Parameters

toWaitFor:Transaction: transaction to wait for
mapName:String: name of the map containing blocking entry
key:Object: of the blocking entry
timeoutMillis:int: timeout in milliseconds, -1 for default

Returns:boolean

true if other transaction was closed and this one can proceed, false if timed out

waitForThisToEnd	back to summary
private synchronized boolean waitForThisToEnd(int millis, Transaction waiter)

public final Class Transaction

Field Summary

Constructor Summary

Method Summary

Field Detail

Constructor Detail

Method Detail