org.datanucleus

Class JTATransactionImpl

java.lang.Object

org.datanucleus.TransactionImpl

org.datanucleus.JTATransactionImpl

All Implemented Interfaces:

Synchronization, Transaction

public class JTATransactionImpl
extends TransactionImpl
implements Synchronization

Transaction that is synchronized with a Java Transaction Service (JTA) transaction. Works only in environments where a TransactionManager is present. This transaction joins to the transaction via the TransactionManager, and the TransactionManager notifies this class of completion via the beforeCompletion/afterCompletion callback hooks. This transaction can be configured as "autoJoin" whereby it will try to join when it is created and otherwise when isActive() is called. When it is not set to "autoJoin" the developer has to call

joinTransaction

which will check the current join status and join as necessary.

When this transaction is being used the transactions must be controlled using javax.transaction.UserTransaction, and not using local transactions (e.g PM.currentTransaction().begin()). Should also work for SessionBeans, as per spec UserTransaction reflects SessionBean-based tx demarcation. See also Transaction

Field Summary

Fields

Modifier and Type	Field and Description
protected boolean	autoJoin
protected org.datanucleus.JTATransactionImpl.JoinStatus	joinStatus

Fields inherited from class org.datanucleus.TransactionImpl

rollbackOnly, serializeRead

Fields inherited from interface org.datanucleus.Transaction

TRANSACTION_ISOLATION_OPTION

Method Summary

Modifier and Type	Method and Description
void	afterCompletion(int status) This method is called by the transaction manager after the transaction is committed or rolled back.
void	beforeCompletion() The beforeCompletion method is called by the transaction manager prior to the start of the two-phase transaction commit process.
void	begin() JDO spec "16.1.3 Stateless Session Bean with Bean Managed Transactions": "acquiring a PM without beginning a UserTransaction results in the PM being able to manage transaction boundaries via begin, commit, and rollback methods on JDO Transaction.
void	commit() Allow UserTransaction demarcation
boolean	getIsActive() Similar to "isActive" except that it just returns the "active" flag whereas the isActive() method can also embody rejoining to underlying transactions.
boolean	isActive() Accessor for whether the transaction is active.
boolean	isJoined()
void	joinTransaction() Method to call if you want to join to the underlying UserTransaction.
void	rollback() Allow UserTransaction demarcation
void	setRollbackOnly() Allow UserTransaction demarcation

Methods inherited from class org.datanucleus.TransactionImpl

addTransactionEventListener, bindTransactionEventListener, close, end, flush, getBeginTime, getNontransactionalRead, getNontransactionalWrite, getNontransactionalWriteAutoCommit, getOptimistic, getOptions, getRestoreValues, getRetainValues, getRollbackOnly, getSerializeRead, getSynchronization, internalBegin, internalCommit, internalPostCommit, internalPreCommit, internalPreRollback, internalRollback, isCommitting, preFlush, releaseSavepoint, removeTransactionEventListener, rollbackToSavepoint, setNontransactionalRead, setNontransactionalWrite, setNontransactionalWriteAutoCommit, setOptimistic, setOption, setOption, setOption, setOption, setProperties, setRestoreValues, setRetainValues, setSavepoint, setSerializeRead, setSynchronization

Methods inherited from class java.lang.Object

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

Field Detail

joinStatus

protected org.datanucleus.JTATransactionImpl.JoinStatus joinStatus

autoJoin

protected boolean autoJoin

Method Detail

isJoined

public boolean isJoined()

joinTransaction

public void joinTransaction()

Method to call if you want to join to the underlying UserTransaction. Will be called by isActive() and constructor if "autoJoin" is set, otherwise has to be called by user code.

getIsActive

public boolean getIsActive()

Description copied from class: TransactionImpl

Similar to "isActive" except that it just returns the "active" flag whereas the isActive() method can also embody rejoining to underlying transactions.

Specified by:

getIsActive in interface Transaction

Overrides:

getIsActive in class TransactionImpl

Returns:

The "active" flag

isActive

public boolean isActive()

Accessor for whether the transaction is active. The UserTransaction is considered active if its status is anything other than Status.STATUS_NO_TRANSACTION, i.e. when the current thread is associated with a JTA transaction. Note that this will attempt to join if not yet joined

Specified by:

isActive in interface Transaction

Overrides:

isActive in class TransactionImpl

Returns:

Whether the transaction is active.

begin

public void begin()

JDO spec "16.1.3 Stateless Session Bean with Bean Managed Transactions": "acquiring a PM without beginning a UserTransaction results in the PM being able to manage transaction boundaries via begin, commit, and rollback methods on JDO Transaction. The PM will automatically begin the User-Transaction during Transaction.begin and automatically commit the UserTransaction during Transaction.commit"

Specified by:

begin in interface Transaction

Overrides:

begin in class TransactionImpl

commit

public void commit()

Allow UserTransaction demarcation

Specified by:

commit in interface Transaction

Overrides:

commit in class TransactionImpl

rollback

public void rollback()

Allow UserTransaction demarcation

Specified by:

rollback in interface Transaction

Overrides:

rollback in class TransactionImpl

setRollbackOnly

public void setRollbackOnly()

Allow UserTransaction demarcation

Specified by:

setRollbackOnly in interface Transaction

Overrides:

setRollbackOnly in class TransactionImpl

beforeCompletion

public void beforeCompletion()

The beforeCompletion method is called by the transaction manager prior to the start of the two-phase transaction commit process.

Specified by:

beforeCompletion in interface Synchronization

afterCompletion

public void afterCompletion(int status)

This method is called by the transaction manager after the transaction is committed or rolled back. Must be synchronised because some callers expect to be owner of this object's monitor (internalPostCommit() calls closeSQLConnection() which calls notifyAll()).

Specified by:

afterCompletion in interface Synchronization

Parameters:

status - The status