com.sleepycat.client.collections

Class CurrentTransaction

java.lang.Object

com.sleepycat.client.collections.CurrentTransaction

public class CurrentTransaction
extends java.lang.Object

Provides access to the current transaction for the current thread within the context of a Berkeley DB environment. This class provides explicit transaction control beyond that provided by the TransactionRunner class. However, both methods of transaction control manage per-thread transactions.

Method Summary

Modifier and Type	Method and Description
STransaction	abortTransaction() Aborts the transaction that is active for the current thread for this environment and makes the parent transaction (if any) the current transaction.
STransaction	beginTransaction(STransactionConfig config) Begins a new transaction for this environment and associates it with the current thread.
STransaction	commitTransaction() Commits the transaction that is active for the current thread for this environment and makes the parent transaction (if any) the current transaction.
SEnvironment	getEnvironment() Returns the underlying Berkeley DB environment.
static CurrentTransaction	getInstance(SEnvironment env) Gets the CurrentTransaction accessor for a specified Berkeley DB environment.
STransaction	getTransaction() Returns the transaction associated with the current thread for this environment, or null if no transaction is active.

Methods inherited from class java.lang.Object

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

Method Detail

getInstance

public static CurrentTransaction getInstance(SEnvironment env)

Gets the CurrentTransaction accessor for a specified Berkeley DB environment. This method always returns the same reference when called more than once with the same environment parameter.

Parameters:

env - is an open Berkeley DB environment.

Returns:

the CurrentTransaction accessor for the given environment, or null if the environment is not transactional.

getEnvironment

public final SEnvironment getEnvironment()

Returns the underlying Berkeley DB environment.

Returns:

the SEnvironment.

getTransaction

public final STransaction getTransaction()

Returns the transaction associated with the current thread for this environment, or null if no transaction is active.

Returns:

the STransaction.

beginTransaction

public final STransaction beginTransaction(STransactionConfig config)
                                    throws SDatabaseException

Begins a new transaction for this environment and associates it with the current thread. If a transaction is already active for this environment and thread, a nested transaction will be created.

Parameters:

config - the transaction configuration used for calling SEnvironment.beginTransaction(com.sleepycat.client.STransaction, com.sleepycat.client.STransactionConfig), or null to use the default configuration.

Returns:

the new transaction.

Throws:

SDatabaseException - if the transaction cannot be started, in which case any existing transaction is not affected.

java.lang.IllegalStateException - if a transaction is already active and nested transactions are not supported by the environment.

commitTransaction

public final STransaction commitTransaction()
                                     throws SDatabaseException,
                                            java.lang.IllegalStateException

Commits the transaction that is active for the current thread for this environment and makes the parent transaction (if any) the current transaction.

Returns:

the parent transaction or null if the committed transaction was not nested.

Throws:

SDatabaseException - if an error occurs committing the transaction. The transaction will still be closed and the parent transaction will become the current transaction.

java.lang.IllegalStateException - if no transaction is active for the current thread for this environment.

abortTransaction

public final STransaction abortTransaction()
                                    throws SDatabaseException,
                                           java.lang.IllegalStateException

Aborts the transaction that is active for the current thread for this environment and makes the parent transaction (if any) the current transaction.

Returns:

the parent transaction or null if the aborted transaction was not nested.

Throws:

SDatabaseException - if an error occurs aborting the transaction. The transaction will still be closed and the parent transaction will become the current transaction.

java.lang.IllegalStateException - if no transaction is active for the current thread for this environment.