weblogic.transaction

Interface XAResource

All Superinterfaces:

javax.transaction.xa.XAResource

public interface XAResource
extends javax.transaction.xa.XAResource

This is an optional interface that XA resource provider can implement to communicate extra information to the Transaction Manager.

Field Summary

Fields

Modifier and Type	Field and Description
static int	DETERMINERXIDSCAN Flag for recover scan used internally to return array of Xids of all determiners delimited by special Xids that indicate the determiner subsequent Xids belong to.
static int	TMCLUSTERSCAN Scan the entire cluster
static int	TMCLUSTERSCANPASSTHROUGH Provides client-side override if server has cluster-wide recovery enabled

Fields inherited from interface javax.transaction.xa.XAResource

TMENDRSCAN, TMFAIL, TMJOIN, TMNOFLAGS, TMONEPHASE, TMRESUME, TMSTARTRSCAN, TMSUCCESS, TMSUSPEND, XA_OK, XA_RDONLY

Method Summary

Modifier and Type	Method and Description
boolean	detectedUnavailable() Transaction Manager calls this method of the XA resource when it detects it to be unresponsive (i.e.
int	getDelistFlag() Normally, the Transaction Manager determines the delist flag to be used for the XAResource.end() operations.

Methods inherited from interface javax.transaction.xa.XAResource

commit, end, forget, getTransactionTimeout, isSameRM, prepare, recover, rollback, setTransactionTimeout, start

Field Detail

TMCLUSTERSCAN

static final int TMCLUSTERSCAN

Scan the entire cluster

See Also:

Constant Field Values

TMCLUSTERSCANPASSTHROUGH

static final int TMCLUSTERSCANPASSTHROUGH

Provides client-side override if server has cluster-wide recovery enabled

See Also:

Constant Field Values

DETERMINERXIDSCAN

static final int DETERMINERXIDSCAN

Flag for recover scan used internally to return array of Xids of all determiners delimited by special Xids that indicate the determiner subsequent Xids belong to.

See Also:

Constant Field Values

Method Detail

getDelistFlag

int getDelistFlag()

Normally, the Transaction Manager determines the delist flag to be used for the XAResource.end() operations. However, for some resource providers, calling XAResource.end() with TMSUSPEND flag may be more expensive than calling XAResource.end() with TMSUCCESS, due to e.g. the need to maintain open cursors in the former case. If this interface is implemented, the Transaction Manager calls this method to obtain the delist flag to be used. This provide opportunity for resource provider to perform optimizations during XAResource.end().

Returns:

delist flag

detectedUnavailable

boolean detectedUnavailable()

Transaction Manager calls this method of the XA resource when it detects it to be unresponsive (i.e. no pending XA requests is replied after MaxXACallMillis.) This unresponsiveness could be due to problems with the particular transactions of the pending XA requests, or it could be in fact due to general unavailability of the resource. Resource provider which implements this method is expected to reply to the Transaction Manager about the actual health status of the resource. If the resource is indeed unavailable, this is also the notification for it to schedule an asynchronous refresh and re-registration. It is important that the resource provider DO NOT BLOCK for an extended period of time at this method call. To re-register with the Transaction Manager, the resource provider can call weblogic.transaction.TransactionManager's unregisterResource method, followed by registerResource, or registerStaticResource, or registerDynamicResource. If this interface is not implemented, the Transaction Manager will mark the resource to be unhealthy once it detects it to be unresponsive. Also, in this case, it is up to the resource provider to refresh and re-register at appropriate time. If nothing is done explicitly, the Transaction Manager will declare the resource healthy again after MaxResourceUnavailableMillis.

Returns:

whether the resource is healthy