BEA WebLogic Server 9.1 API Reference

weblogic.transaction
Interface XAResource

All Superinterfaces:

XAResource

public interface XAResource

extends XAResource

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

Copyright © 2005 BEA Systems, Inc. All Rights Reserved.

Field Summary

Fields inherited from interface javax.transaction.xa.XAResource

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

Method Summary

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

Method Detail

detectedUnavailable

public 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

getDelistFlag

public 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