Modifier and Type	Class and Description
public static class	SequenceUpdater.BulkInsertUpdater Implementation of SequenceUpdater for use with the bulk-insert optimization used by InsertResultSet.
public static class	SequenceUpdater.SyssequenceUpdater Specific implementation of SequenceUpdater for the sequences managed by SYSSEQUENCES.

Modifier and Type	Field and Description
protected DataDictionaryImpl	_dd
protected SequenceGenerator	_sequenceGenerator This is the object which allocates ranges of sequence values
protected String	_uuidString This is the key used to lookup this generator in the cache.

Access	Constructor and Description
public	SequenceUpdater() No-arg constructor to satisfy the Cacheable contract
public	SequenceUpdater(DataDictionaryImpl dd) Normal constructor

Method Summary

Modifier and Type	Method and Description
public void	clean(boolean True if the object will be removed forRemove) Implements org.apache.derby.iapi.services.cache.Cacheable.clean. Clean the object.
public void	clearIdentity() Implements org.apache.derby.iapi.services.cache.Cacheable.clearIdentity. Put the object into the No Identity state.
public Cacheable	createIdentity(Object The handle on the cacheable key, Object Creation details createParameter) Implements org.apache.derby.iapi.services.cache.Cacheable.createIdentity. Create a new item.
protected abstract SequenceGenerator	createSequenceGenerator(TransactionController readOnlyTC) Initialize the sequence generator.
public synchronized SequenceUpdater.BulkInsertUpdater	getBulkInsertUpdater(boolean True if the counter should be re-initialized to its start position. restart) Get the SequenceUpdater used for the bulk-insert optimization in InsertResultSet.
private static Context	getContextOrNull(final String contextID) Must be private so that user code can't call this entry point.
private static ContextService	getContextService() Must be private so that user code can't call this entry point.
public synchronized void	getCurrentValueAndAdvance(NumberDataValue This value is stuffed with the new sequence number. returnValue) Get the next sequence number managed by this generator and advance the number.
public Object	getIdentity() Implements org.apache.derby.iapi.services.cache.Cacheable.getIdentity. Get the identity of this object.
private static LanguageConnectionContext	getLCC()
public boolean	isDirty() Implements org.apache.derby.iapi.services.cache.Cacheable.isDirty. Returns true if the object is dirty.
private boolean	isNumber(String text)
protected SequencePreallocator	makePreallocator(TransactionController tc) Make a new range allocator (called when the generator is instantiated)
private StandardException	missingAllocator(String propertyName, String className, Exception e)
public Long	peekAtCurrentValue() Get the current value of the sequence generator without advancing it.
public synchronized void	reset(Long newValue) Reset the sequence generator to a new start value.
public Cacheable	setIdentity(Object The handle on the cacheable key) Implements org.apache.derby.iapi.services.cache.Cacheable.setIdentity. Set the identity of the object.
private StandardException	tooMuchContentionException() Create an exception to state that there is too much contention on the generator.
private StandardException	unimplementedFeature() Report an unimplemented feature
protected abstract boolean	Returns: Returns true if the value was successfully updated, false if we lost a race with another session. updateCurrentValueOnDisk(TransactionController The transaction to use tc, Long Expected value on disk for this sequence oldValue, Long The value to poke into the system table backing this sequence newValue, boolean Whether to wait for a lock wait) Update the sequence value on disk.
public synchronized boolean	Returns: Returns true if the value was successfully updated, false if we lost a race with another session. updateCurrentValueOnDisk(Long oldValue, Long newValue) Update the value on disk.

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

Field Detail

_dd	back to summary
protected DataDictionaryImpl _dd

_sequenceGenerator	back to summary
protected SequenceGenerator _sequenceGenerator This is the object which allocates ranges of sequence values

_uuidString	back to summary
protected String _uuidString This is the key used to lookup this generator in the cache.

Constructor Detail

SequenceUpdater	back to summary
public SequenceUpdater() No-arg constructor to satisfy the Cacheable contract

SequenceUpdater	back to summary
public SequenceUpdater(DataDictionaryImpl dd) Normal constructor

Method Detail

clean	back to summary
public void clean(boolean forRemove) throws StandardException Implements org.apache.derby.iapi.services.cache.Cacheable.clean. Doc from org.apache.derby.iapi.services.cache.Cacheable.clean. Clean the object. It is up to the object to ensure synchronization of the isDirty() and clean() method calls. If forRemove is true then the object is being removed due to an explict remove request, in this case the cache manager will have called this method regardless of the state of the isDirty() If an exception is thrown the object must be left in the clean state. MT - thread safe - Can be called at any time by the cache manager, it is the responsibility of the object implementing Cacheable to ensure any users of the object do not conflict with the clean call. Parameters forRemove:boolean True if the object will be removed Exceptions StandardException: Standard Derby error policy.

clean

back to summary

public void clean(boolean forRemove) throws StandardException

Implements org.apache.derby.iapi.services.cache.Cacheable.clean.

Doc from org.apache.derby.iapi.services.cache.Cacheable.clean.

Clean the object. It is up to the object to ensure synchronization of the isDirty() and clean() method calls.
If forRemove is true then the object is being removed due to an explict remove request, in this case the cache manager will have called this method regardless of the state of the isDirty()
If an exception is thrown the object must be left in the clean state.
MT - thread safe - Can be called at any time by the cache manager, it is the responsibility of the object implementing Cacheable to ensure any users of the object do not conflict with the clean call.

Parameters

forRemove:boolean: True if the object will be removed

Exceptions

StandardException:: Standard Derby error policy.

clearIdentity	back to summary
public void clearIdentity() Implements org.apache.derby.iapi.services.cache.Cacheable.clearIdentity. Doc from org.apache.derby.iapi.services.cache.Cacheable.clearIdentity. Put the object into the No Identity state. MT - single thread required - Method must only be called be cache manager and the cache manager will guarantee only one thread can be calling it.

clearIdentity

back to summary

public void clearIdentity()

Implements org.apache.derby.iapi.services.cache.Cacheable.clearIdentity.

Doc from org.apache.derby.iapi.services.cache.Cacheable.clearIdentity.

Put the object into the No Identity state.
MT - single thread required - Method must only be called be cache manager and the cache manager will guarantee only one thread can be calling it.

createIdentity	back to summary
public Cacheable createIdentity(Object key, Object createParameter) throws StandardException Implements org.apache.derby.iapi.services.cache.Cacheable.createIdentity. Doc from org.apache.derby.iapi.services.cache.Cacheable.createIdentity. Create a new item. Create a new item and set the identity of the object to represent it. The object will be in the No Identity state, ie. it will have just been created or clearIdentity() was just called. The object must copy the information out of key, not just store a reference to key if the key is not immutable. After this call the expression getIdentity().equals(key) must return true. If the class of the object needs to change (e.g. to support a different format) then the object should create a new object, call its initParameter() with the parameters the original object was called with, set its identity and return a reference to it. The cache manager will discard the reference to the old object. If an exception is thrown the object must be left in the no-identity state. MT - single thread required - Method must only be called be cache manager and the cache manager will guarantee only one thread can be calling it. Parameters key:Object The handle on the cacheable createParameter:Object Creation details Returns:Cacheable an object reference if the object can take on the identity, null otherwise. Exceptions StandardException: If forCreate is true and the object cannot be created.

createIdentity

back to summary

public Cacheable createIdentity(Object key, Object createParameter) throws StandardException

Implements org.apache.derby.iapi.services.cache.Cacheable.createIdentity.

Doc from org.apache.derby.iapi.services.cache.Cacheable.createIdentity.

Create a new item.

Create a new item and set the identity of the object to represent it. The object will be in the No Identity state, ie. it will have just been created or clearIdentity() was just called.
The object must copy the information out of key, not just store a reference to key if the key is not immutable. After this call the expression getIdentity().equals(key) must return true.

If the class of the object needs to change (e.g. to support a different format) then the object should create a new object, call its initParameter() with the parameters the original object was called with, set its identity and return a reference to it. The cache manager will discard the reference to the old object.
If an exception is thrown the object must be left in the no-identity state.
MT - single thread required - Method must only be called be cache manager and the cache manager will guarantee only one thread can be calling it.

Parameters

key:Object: The handle on the cacheable
createParameter:Object: Creation details

Returns:Cacheable

an object reference if the object can take on the identity, null otherwise.

Exceptions

StandardException:: If forCreate is true and the object cannot be created.

createSequenceGenerator	back to summary
protected abstract SequenceGenerator createSequenceGenerator(TransactionController readOnlyTC) throws StandardException Initialize the sequence generator. Work is done inside a read-only subtransaction of the session's execution transaction.

getBulkInsertUpdater	back to summary
public synchronized SequenceUpdater.BulkInsertUpdater getBulkInsertUpdater(boolean restart) throws StandardException Get the SequenceUpdater used for the bulk-insert optimization in InsertResultSet. Parameters restart:boolean True if the counter should be re-initialized to its start position.

getBulkInsertUpdater

back to summary

public synchronized SequenceUpdater.BulkInsertUpdater getBulkInsertUpdater(boolean restart) throws StandardException

Get the SequenceUpdater used for the bulk-insert optimization in InsertResultSet.

Parameters

restart:boolean: True if the counter should be re-initialized to its start position.

getContextOrNull	back to summary
private static Context getContextOrNull(final String contextID) Must be private so that user code can't call this entry point.

getContextService	back to summary
private static ContextService getContextService() Must be private so that user code can't call this entry point.

getCurrentValueAndAdvance	back to summary
public synchronized void getCurrentValueAndAdvance(NumberDataValue returnValue) throws StandardException Get the next sequence number managed by this generator and advance the number. Could raise an exception if the legal range is exhausted and wrap-around is not allowed. Only one thread at a time is allowed through here. We do not want a race between the two calls to the sequence generator: getCurrentValueAndAdvance() and allocateNewRange(). Parameters returnValue:NumberDataValue This value is stuffed with the new sequence number.

getCurrentValueAndAdvance

back to summary

public synchronized void getCurrentValueAndAdvance(NumberDataValue returnValue) throws StandardException

Get the next sequence number managed by this generator and advance the number. Could raise an exception if the legal range is exhausted and wrap-around is not allowed. Only one thread at a time is allowed through here. We do not want a race between the two calls to the sequence generator: getCurrentValueAndAdvance() and allocateNewRange().

Parameters

returnValue:NumberDataValue: This value is stuffed with the new sequence number.

getIdentity	back to summary
public Object getIdentity() Implements org.apache.derby.iapi.services.cache.Cacheable.getIdentity. Doc from org.apache.derby.iapi.services.cache.Cacheable.getIdentity. Get the identity of this object. MT - thread safe. Returns:Object the object identity

getIdentity

back to summary

public Object getIdentity()

Implements org.apache.derby.iapi.services.cache.Cacheable.getIdentity.

Doc from org.apache.derby.iapi.services.cache.Cacheable.getIdentity.

Get the identity of this object.
MT - thread safe.

Returns:Object: the object identity

getLCC	back to summary
private static LanguageConnectionContext getLCC()

isDirty	back to summary
public boolean isDirty() Implements org.apache.derby.iapi.services.cache.Cacheable.isDirty. Doc from org.apache.derby.iapi.services.cache.Cacheable.isDirty. Returns true if the object is dirty. May be called when the object is kept or unkept. MT - thread safe Returns:boolean true if the object is dirty

isDirty

back to summary

public boolean isDirty()

Implements org.apache.derby.iapi.services.cache.Cacheable.isDirty.

Doc from org.apache.derby.iapi.services.cache.Cacheable.isDirty.

Returns true if the object is dirty. May be called when the object is kept or unkept.
MT - thread safe

Returns:boolean: true if the object is dirty

isNumber	back to summary
private boolean isNumber(String text)

makePreallocator	back to summary
protected SequencePreallocator makePreallocator(TransactionController tc) throws StandardException Make a new range allocator (called when the generator is instantiated)

missingAllocator	back to summary
private StandardException missingAllocator(String propertyName, String className, Exception e)

peekAtCurrentValue	back to summary
public Long peekAtCurrentValue() throws StandardException Get the current value of the sequence generator without advancing it. May return null if the generator is exhausted.

reset	back to summary
public synchronized void reset(Long newValue) throws StandardException Reset the sequence generator to a new start value. This is used by the special bulk-insert optimization in InsertResultSet.

setIdentity back to summary

setIdentity	back to summary
public Cacheable setIdentity(Object key) throws StandardException Implements org.apache.derby.iapi.services.cache.Cacheable.setIdentity. Doc from org.apache.derby.iapi.services.cache.Cacheable.setIdentity. Set the identity of the object. Set the identity of the object to represent an item that already exists, e.g. an existing container. The object will be in the No Identity state, ie. it will have just been created or clearIdentity() was just called. The object must copy the information out of key, not just store a reference to key. After this call the expression getIdentity().equals(key) must return true. If the class of the object needs to change (e.g. to support a different format) then the object should create a new object, call its initParameter() with the parameters the original object was called with, set its identity and return a reference to it. The cache manager will discard the reference to the old object. If an exception is thrown the object must be left in the no-identity state. MT - single thread required - Method must only be called be cache manager and the cache manager will guarantee only one thread can be calling it. Parameters key:Object The handle on the cacheable Returns:Cacheable an object reference if the object can take on the identity, null otherwise. Exceptions StandardException: Thrown on error See Also `Cacheable#setIdentity`

public Cacheable setIdentity(Object key) throws StandardException

Implements org.apache.derby.iapi.services.cache.Cacheable.setIdentity.

Doc from org.apache.derby.iapi.services.cache.Cacheable.setIdentity.

Set the identity of the object.

Set the identity of the object to represent an item that already exists, e.g. an existing container. The object will be in the No Identity state, ie. it will have just been created or clearIdentity() was just called.
The object must copy the information out of key, not just store a reference to key. After this call the expression getIdentity().equals(key) must return true.
If the class of the object needs to change (e.g. to support a different format) then the object should create a new object, call its initParameter() with the parameters the original object was called with, set its identity and return a reference to it. The cache manager will discard the reference to the old object.
If an exception is thrown the object must be left in the no-identity state.
MT - single thread required - Method must only be called be cache manager and the cache manager will guarantee only one thread can be calling it.

Parameters

key:Object: The handle on the cacheable

Returns:Cacheable

an object reference if the object can take on the identity, null otherwise.

Exceptions

StandardException:: Thrown on error

See Also

Cacheable#setIdentity

tooMuchContentionException	back to summary
private StandardException tooMuchContentionException() Create an exception to state that there is too much contention on the generator. For backward compatibility reasons, different messages are needed by sequences and identities. See DERBY-5426.

unimplementedFeature	back to summary
private StandardException unimplementedFeature() Report an unimplemented feature

updateCurrentValueOnDisk	back to summary
protected abstract boolean updateCurrentValueOnDisk(TransactionController tc, Long oldValue, Long newValue, boolean wait) throws StandardException Update the sequence value on disk. This method does its work in a subtransaction of the user's execution transaction. Parameters tc:TransactionController The transaction to use oldValue:Long Expected value on disk for this sequence newValue:Long The value to poke into the system table backing this sequence wait:boolean Whether to wait for a lock Returns:boolean Returns true if the value was successfully updated, false if we lost a race with another session. Exceptions StandardException: May throw an exception if a lock can't be obtained.

updateCurrentValueOnDisk

back to summary

protected abstract boolean updateCurrentValueOnDisk(TransactionController tc, Long oldValue, Long newValue, boolean wait) throws StandardException

Update the sequence value on disk. This method does its work in a subtransaction of the user's execution transaction.

Parameters

tc:TransactionController: The transaction to use
oldValue:Long: Expected value on disk for this sequence
newValue:Long: The value to poke into the system table backing this sequence
wait:boolean: Whether to wait for a lock

Returns:boolean

Returns true if the value was successfully updated, false if we lost a race with another session.

Exceptions

StandardException:: May throw an exception if a lock can't be obtained.

updateCurrentValueOnDisk	back to summary
public synchronized boolean updateCurrentValueOnDisk(Long oldValue, Long newValue) throws StandardException Update the value on disk. Does its work in a subtransaction of the user's execution transaction. If that fails, raises a TOO MUCH CONTENTION exception. Returns:boolean Returns true if the value was successfully updated, false if we lost a race with another session.

updateCurrentValueOnDisk

back to summary

public synchronized boolean updateCurrentValueOnDisk(Long oldValue, Long newValue) throws StandardException

Update the value on disk. Does its work in a subtransaction of the user's execution transaction. If that fails, raises a TOO MUCH CONTENTION exception.

Returns:boolean: Returns true if the value was successfully updated, false if we lost a race with another session.

org.apache.derby.impl.sql.catalog back to summary

public final Class SequenceUpdater.BulkInsertUpdater

Class Inheritance

extends SequenceUpdater
implements BulkInsertCounter

java.lang.Object
org.apache.derby.impl.sql.catalog.SequenceUpdater
org.apache.derby.impl.sql.catalog.SequenceUpdater.BulkInsertUpdater

All Implemented Interfaces

org.apache.derby.iapi.sql.dictionary.BulkInsertCounter

Implementation of SequenceUpdater for use with the bulk-insert optimization used by InsertResultSet. This BulkInsertUpdater doesn't really write to disk. It is assumed that the BulkInsertUpdater will only be used by the bulk-insert code, where the user has exclusive write-access on the table whose identity column is backed by the original SequenceUpdater. At the end of bulk-insert, the current value of the BulkInsertUpdater is written to disk by other code.

Field Summary

Inherited from org.apache.derby.impl.sql.catalog.SequenceUpdater:: _dd _sequenceGenerator _uuidString

Constructor Summary

Access	Constructor and Description
public	BulkInsertUpdater()
public	BulkInsertUpdater(SequenceUpdater originalUpdater, boolean restart)

Method Summary

Modifier and Type	Method and Description
protected SequenceGenerator	createSequenceGenerator(TransactionController readOnlyTC) Implements abstract org.apache.derby.impl.sql.catalog.SequenceUpdater.createSequenceGenerator. Initialize the sequence generator.
protected boolean	updateCurrentValueOnDisk(TransactionController The transaction to use tc, Long Expected value on disk for this sequence oldValue, Long The value to poke into the system table backing this sequence newValue, boolean Whether to wait for a lock wait) Implements abstract org.apache.derby.impl.sql.catalog.SequenceUpdater.updateCurrentValueOnDisk. Update the sequence value on disk.

Inherited from org.apache.derby.impl.sql.catalog.SequenceUpdater:: clean clearIdentity createIdentity getBulkInsertUpdater getCurrentValueAndAdvance getIdentity isDirty makePreallocator peekAtCurrentValue reset setIdentity updateCurrentValueOnDisk

Constructor Detail

BulkInsertUpdater	back to summary
public BulkInsertUpdater()

BulkInsertUpdater	back to summary
public BulkInsertUpdater(SequenceUpdater originalUpdater, boolean restart)

Method Detail

createSequenceGenerator	back to summary
protected SequenceGenerator createSequenceGenerator(TransactionController readOnlyTC) throws StandardException Implements abstract org.apache.derby.impl.sql.catalog.SequenceUpdater.createSequenceGenerator. Doc from org.apache.derby.impl.sql.catalog.SequenceUpdater.createSequenceGenerator. Initialize the sequence generator. Work is done inside a read-only subtransaction of the session's execution transaction.

createSequenceGenerator

back to summary

protected SequenceGenerator createSequenceGenerator(TransactionController readOnlyTC) throws StandardException

Implements abstract org.apache.derby.impl.sql.catalog.SequenceUpdater.createSequenceGenerator.

Doc from org.apache.derby.impl.sql.catalog.SequenceUpdater.createSequenceGenerator.

Initialize the sequence generator. Work is done inside a read-only subtransaction of the session's execution transaction.

updateCurrentValueOnDisk	back to summary
protected boolean updateCurrentValueOnDisk(TransactionController tc, Long oldValue, Long newValue, boolean wait) throws StandardException Implements abstract org.apache.derby.impl.sql.catalog.SequenceUpdater.updateCurrentValueOnDisk. Doc from org.apache.derby.impl.sql.catalog.SequenceUpdater.updateCurrentValueOnDisk. Update the sequence value on disk. This method does its work in a subtransaction of the user's execution transaction. Parameters tc:TransactionController The transaction to use oldValue:Long Expected value on disk for this sequence newValue:Long The value to poke into the system table backing this sequence wait:boolean Whether to wait for a lock Returns:boolean Returns true if the value was successfully updated, false if we lost a race with another session. Exceptions StandardException: May throw an exception if a lock can't be obtained.

updateCurrentValueOnDisk

back to summary

protected boolean updateCurrentValueOnDisk(TransactionController tc, Long oldValue, Long newValue, boolean wait) throws StandardException

Implements abstract org.apache.derby.impl.sql.catalog.SequenceUpdater.updateCurrentValueOnDisk.

Doc from org.apache.derby.impl.sql.catalog.SequenceUpdater.updateCurrentValueOnDisk.

Update the sequence value on disk. This method does its work in a subtransaction of the user's execution transaction.

Parameters

tc:TransactionController: The transaction to use
oldValue:Long: Expected value on disk for this sequence
newValue:Long: The value to poke into the system table backing this sequence
wait:boolean: Whether to wait for a lock

Returns:boolean

Returns true if the value was successfully updated, false if we lost a race with another session.

Exceptions

StandardException:: May throw an exception if a lock can't be obtained.

org.apache.derby.impl.sql.catalog back to summary

public final Class SequenceUpdater.SyssequenceUpdater

Class Inheritance

extends SequenceUpdater

java.lang.Object
org.apache.derby.impl.sql.catalog.SequenceUpdater
org.apache.derby.impl.sql.catalog.SequenceUpdater.SyssequenceUpdater

Specific implementation of SequenceUpdater for the sequences managed by SYSSEQUENCES.

Field Summary

Modifier and Type	Field and Description
private RowLocation	_sequenceRowLocation

Inherited from org.apache.derby.impl.sql.catalog.SequenceUpdater:: _dd _sequenceGenerator _uuidString

Constructor Summary

Access	Constructor and Description
public	SyssequenceUpdater()
public	SyssequenceUpdater(DataDictionaryImpl dd)

Method Summary

Modifier and Type	Method and Description
protected SequenceGenerator	createSequenceGenerator(TransactionController readOnlyTC) Implements abstract org.apache.derby.impl.sql.catalog.SequenceUpdater.createSequenceGenerator. Initialize the sequence generator.
protected boolean	updateCurrentValueOnDisk(TransactionController The transaction to use tc, Long Expected value on disk for this sequence oldValue, Long The value to poke into the system table backing this sequence newValue, boolean Whether to wait for a lock wait) Implements abstract org.apache.derby.impl.sql.catalog.SequenceUpdater.updateCurrentValueOnDisk. Update the sequence value on disk.

Inherited from org.apache.derby.impl.sql.catalog.SequenceUpdater:: clean clearIdentity createIdentity getBulkInsertUpdater getCurrentValueAndAdvance getIdentity isDirty makePreallocator peekAtCurrentValue reset setIdentity updateCurrentValueOnDisk

Field Detail

_sequenceRowLocation	back to summary
private RowLocation _sequenceRowLocation

Constructor Detail

SyssequenceUpdater	back to summary
public SyssequenceUpdater()

SyssequenceUpdater	back to summary
public SyssequenceUpdater(DataDictionaryImpl dd)

Method Detail

createSequenceGenerator	back to summary
protected SequenceGenerator createSequenceGenerator(TransactionController readOnlyTC) throws StandardException Implements abstract org.apache.derby.impl.sql.catalog.SequenceUpdater.createSequenceGenerator. Doc from org.apache.derby.impl.sql.catalog.SequenceUpdater.createSequenceGenerator. Initialize the sequence generator. Work is done inside a read-only subtransaction of the session's execution transaction.

createSequenceGenerator

back to summary

protected SequenceGenerator createSequenceGenerator(TransactionController readOnlyTC) throws StandardException

Implements abstract org.apache.derby.impl.sql.catalog.SequenceUpdater.createSequenceGenerator.

Doc from org.apache.derby.impl.sql.catalog.SequenceUpdater.createSequenceGenerator.

Initialize the sequence generator. Work is done inside a read-only subtransaction of the session's execution transaction.

updateCurrentValueOnDisk	back to summary
protected boolean updateCurrentValueOnDisk(TransactionController tc, Long oldValue, Long newValue, boolean wait) throws StandardException Implements abstract org.apache.derby.impl.sql.catalog.SequenceUpdater.updateCurrentValueOnDisk. Doc from org.apache.derby.impl.sql.catalog.SequenceUpdater.updateCurrentValueOnDisk. Update the sequence value on disk. This method does its work in a subtransaction of the user's execution transaction. Parameters tc:TransactionController The transaction to use oldValue:Long Expected value on disk for this sequence newValue:Long The value to poke into the system table backing this sequence wait:boolean Whether to wait for a lock Returns:boolean Returns true if the value was successfully updated, false if we lost a race with another session. Exceptions StandardException: May throw an exception if a lock can't be obtained.

updateCurrentValueOnDisk

back to summary

protected boolean updateCurrentValueOnDisk(TransactionController tc, Long oldValue, Long newValue, boolean wait) throws StandardException

Implements abstract org.apache.derby.impl.sql.catalog.SequenceUpdater.updateCurrentValueOnDisk.

Doc from org.apache.derby.impl.sql.catalog.SequenceUpdater.updateCurrentValueOnDisk.

Update the sequence value on disk. This method does its work in a subtransaction of the user's execution transaction.

Parameters

tc:TransactionController: The transaction to use
oldValue:Long: Expected value on disk for this sequence
newValue:Long: The value to poke into the system table backing this sequence
wait:boolean: Whether to wait for a lock

Returns:boolean

Returns true if the value was successfully updated, false if we lost a race with another session.

Exceptions

StandardException:: May throw an exception if a lock can't be obtained.

public abstract Class SequenceUpdater

Nested and Inner Type Summary

Field Summary

Constructor Summary

Method Summary

Field Detail

Constructor Detail

Method Detail

public final Class SequenceUpdater.BulkInsertUpdater

Field Summary

Constructor Summary

Method Summary

Constructor Detail

Method Detail

public final Class SequenceUpdater.SyssequenceUpdater

Field Summary

Constructor Summary

Method Summary

Field Detail

Constructor Detail

Method Detail