org.openorb.ots.xa
Class XACoordinator

java.lang.Object
  org.omg.PortableServer.Servant
      org.omg.CosTransactions.ResourcePOA
          org.openorb.ots.xa.XACoordinator

All Implemented Interfaces:

org.omg.CORBA.portable.InvokeHandler, ResourceOperations

public class XACoordinator
extends ResourcePOA

This class is a coordinator that manages XA Resources.

Author:

Jerome Daniel

Constructor Summary

XACoordinator(XID ots_xid, Coordinator coordinator, Current current, org.omg.PortableInterceptor.ORBInitInfo info, org.apache.avalon.framework.logger.Logger logger)
Constructor

Method Summary

void	commit_one_phase() If possible, the resource should commit all changes made as part of the transaction.
void	commit() If necessary, the resource should commit all changes made as part of the transaction.
void	endXAResource(javax.transaction.xa.XAResource resource, boolean success) End the usage of an XA resource
void	forget() This operation is performed only if the resource raised a heuristic outcome exception to rollback, commit, or commit_one_phase.
org.apache.avalon.framework.logger.Logger	getLogger()
Vote	prepare() This operation is invoked to begin the two-phase commit protocol on the resource.
void	registerXAResource(javax.transaction.xa.XAResource resource) Add an XA resource.
void	rollback_after_prepare() This operation is used to rollback all prepared XA resources.
void	rollback() If necessary, the resource should rollback all changes made as part of the transaction.

Methods inherited from class org.omg.CosTransactions.ResourcePOA

_all_interfaces, _invoke, _this, _this

Methods inherited from class org.omg.PortableServer.Servant

_default_POA, _get_delegate, _get_interface_def, _is_a, _non_existent, _object_id, _orb, _poa, _set_delegate, _this_object, _this_object

Methods inherited from class java.lang.Object

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

Constructor Detail

XACoordinator

public XACoordinator(XID ots_xid,
                     Coordinator coordinator,
                     Current current,
                     org.omg.PortableInterceptor.ORBInitInfo info,
                     org.apache.avalon.framework.logger.Logger logger)

Constructor

Method Detail

prepare

public Vote prepare()
             throws HeuristicMixed,
                    HeuristicHazard

This operation is invoked to begin the two-phase commit protocol on the resource. The resource can respond in several ways, represented by the Vote result. If no persistent data associated with the resource has been modified by the transaction, the resource can return VoteReadOnly. After receiving this response, the Transaction Service is not required to perform any additional operations on this resource. Furthermore, the resource can forget all knowledge of the transaction. If the resource is able to write (or has already written) all the data needed to commit the transaction to stable storage, as well as an indication that it has prepared the transaction, it can return VoteCommit. After receiving this response, the Transaction Service is required to eventually perform either the commit or the rollback operation on this object. To support recovery, the resource should store the RecoveryCoordinator object reference in stable storage. The resource can return VoteRollback under any circumstances, including not having any knowledge about the transaction (which might happen after a crash). If this response is returned, the transaction must be rolled back. Furthermore, the Transaction Service is not required to perform any additional operations on this resource. After returning this response, the resource can forget all knowledge of the transaction. The resource reports inconsistent outcomes using the HeuristicMixed and HeuristicHazard exceptions. Heuristic outcomes occur when a resource acts as a sub-coordinator and at least one of its resources takes a heuristic decision after a VoteCommit return.

Throws:

HeuristicMixed

HeuristicHazard

rollback

public void rollback()
              throws HeuristicCommit,
                     HeuristicMixed,
                     HeuristicHazard

If necessary, the resource should rollback all changes made as part of the transaction. If the resource has forgotten the transaction, it should do nothing. The heuristic outcome exceptions are used to report heuristic decisions related to the resource. If a heuristic outcome exception is raised, the resource must remember this outcome until the forget operation is performed so that it can return the same outcome in case rollback is performed again. Otherwise, the resource can immediately forget all knowledge of the transaction.

Throws:

HeuristicCommit

HeuristicMixed

HeuristicHazard

commit

public void commit()
            throws NotPrepared,
                   HeuristicRollback,
                   HeuristicMixed,
                   HeuristicHazard

If necessary, the resource should commit all changes made as part of the transaction. If the resource has forgotten the transaction, it should do nothing. The heuristic outcome exceptions are used to report heuristic decisions related to the resource. If a heuristic outcome exception is raised, the resource must remember this outcome until the forget operation is performed so that it can return the same outcome in case commit is performed again. Otherwise, the resource can immediately forget all knowledge of the transaction. The NotPrepared exception is raised if the commit operation is performed without first performing the prepare operation.

Throws:

NotPrepared

HeuristicRollback

HeuristicMixed

HeuristicHazard

commit_one_phase

public void commit_one_phase()
                      throws HeuristicHazard

If possible, the resource should commit all changes made as part of the transaction. If it cannot, it should raise the TRANSACTION_ROLLEDBACK standard exception. If a failure occurs during commit_one_phase, it must be retried when the failure is repaired. Since their can only be a single resource, the HeuristicHazard exception is used to report heuristic decisions related to that resource. If a heuristic exception is raised, the resource must remember this outcome until the forget operation is performed so that it can return the same outcome in case commit_one_phase is performed again. Otherwise, the resource can immediately forget all knowledge of the transaction.

Throws:

HeuristicHazard

forget

public void forget()

This operation is performed only if the resource raised a heuristic outcome exception to rollback, commit, or commit_one_phase. Once the coordinator has determined that the heuristic situation has been addressed, it should issue forget on the resource. The resource can forget all knowledge of the transaction.

rollback_after_prepare

public void rollback_after_prepare()
                            throws HeuristicCommit,
                                   HeuristicMixed,
                                   HeuristicHazard

This operation is used to rollback all prepared XA resources.

Throws:

HeuristicCommit

HeuristicMixed

HeuristicHazard

registerXAResource

public void registerXAResource(javax.transaction.xa.XAResource resource)

Add an XA resource.

endXAResource

public void endXAResource(javax.transaction.xa.XAResource resource,
                          boolean success)

End the usage of an XA resource

getLogger

public org.apache.avalon.framework.logger.Logger getLogger()