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XAResource.java API Doc Glassfish v2 API 13500 Fri May 04 22:35:24 BST 2007 javax.transaction.xa

XAResource

public interface XAResource

The XAResource interface is a Java mapping of the industry standard XA interface based on the X/Open CAE Specification (Distributed Transaction Processing: The XA Specification).

The XA interface defines the contract between a Resource Manager and a Transaction Manager in a distributed transaction processing (DTP) environment. A JDBC driver or a JMS provider implements this interface to support the association between a global transaction and a database or message service connection.

The XAResource interface can be supported by any transactional resource that is intended to be used by application programs in an environment where transactions are controlled by an external transaction manager. An example of such a resource is a database management system. An application may access data through multiple database connections. Each database connection is enlisted with the transaction manager as a transactional resource. The transaction manager obtains an XAResource for each connection participating in a global transaction. The transaction manager uses the start method to associate the global transaction with the resource, and it uses the end method to disassociate the transaction from the resource. The resource manager is responsible for associating the global transaction to all work performed on its data between the start and end method invocations.

At transaction commit time, the resource managers are informed by the transaction manager to prepare, commit, or rollback a transaction according to the two-phase commit protocol.

Fields Summary
public static final int
TMENDRSCAN
Ends a recovery scan.
public static final int
TMFAIL
Disassociates the caller and marks the transaction branch rollback-only.
public static final int
TMJOIN
Caller is joining existing transaction branch.
public static final int
TMNOFLAGS
Use TMNOFLAGS to indicate no flags value is selected.
public static final int
TMONEPHASE
Caller is using one-phase optimization.
public static final int
TMRESUME
Caller is resuming association with a suspended transaction branch.
public static final int
TMSTARTRSCAN
Starts a recovery scan.
public static final int
TMSUCCESS
Disassociates caller from a transaction branch.
public static final int
TMSUSPEND
Caller is suspending (not ending) its association with a transaction branch.
public static final int
XA_RDONLY
The transaction branch has been read-only and has been committed.
public static final int
XA_OK
The transaction work has been prepared normally.
Constructors Summary
Methods Summary
public void commit(javax.transaction.xa.Xid xid, boolean onePhase)
Commits the global transaction specified by xid.
param
xid A global transaction identifier
param
onePhase If true, the resource manager should use a one-phase commit protocol to commit the work done on behalf of xid.
exception
XAException An error has occurred. Possible XAExceptions are XA_HEURHAZ, XA_HEURCOM, XA_HEURRB, XA_HEURMIX, XAER_RMERR, XAER_RMFAIL, XAER_NOTA, XAER_INVAL, or XAER_PROTO.
If the resource manager did not commit the transaction and the parameter onePhase is set to true, the resource manager may throw one of the XA_RB* exceptions. Upon return, the resource manager has rolled back the branch's work and has released all held resources.
public void end(javax.transaction.xa.Xid xid, int flags)
Ends the work performed on behalf of a transaction branch. The resource manager disassociates the XA resource from the transaction branch specified and lets the transaction complete.
If TMSUSPEND is specified in the flags, the transaction branch is temporarily suspended in an incomplete state. The transaction context is in a suspended state and must be resumed via the start method with TMRESUME specified.

If TMFAIL is specified, the portion of work has failed. The resource manager may mark the transaction as rollback-only

If TMSUCCESS is specified, the portion of work has completed successfully.
param
xid A global transaction identifier that is the same as the identifier used previously in the start method.
param
flags One of TMSUCCESS, TMFAIL, or TMSUSPEND.
exception
XAException An error has occurred. Possible XAException values are XAER_RMERR, XAER_RMFAIL, XAER_NOTA, XAER_INVAL, XAER_PROTO, or XA_RB*.
public void forget(javax.transaction.xa.Xid xid)
Tells the resource manager to forget about a heuristically completed transaction branch.
param
xid A global transaction identifier.
exception
XAException An error has occurred. Possible exception values are XAER_RMERR, XAER_RMFAIL, XAER_NOTA, XAER_INVAL, or XAER_PROTO.
public int getTransactionTimeout()
Obtains the current transaction timeout value set for this XAResource instance. If XAResource.setTransactionTimeout was not used prior to invoking this method, the return value is the default timeout set for the resource manager; otherwise, the value used in the previous setTransactionTimeout call is returned.
return
the transaction timeout value in seconds.
exception
XAException An error has occurred. Possible exception values are XAER_RMERR and XAER_RMFAIL.
public boolean isSameRM(javax.transaction.xa.XAResource xares)
This method is called to determine if the resource manager instance represented by the target object is the same as the resouce manager instance represented by the parameter xares.
param
xares An XAResource object whose resource manager instance is to be compared with the resource manager instance of the target object.
return
true if it's the same RM instance; otherwise false.
exception
XAException An error has occurred. Possible exception values are XAER_RMERR and XAER_RMFAIL.
public int prepare(javax.transaction.xa.Xid xid)
Ask the resource manager to prepare for a transaction commit of the transaction specified in xid.
param
xid A global transaction identifier.
exception
XAException An error has occurred. Possible exception values are: XA_RB*, XAER_RMERR, XAER_RMFAIL, XAER_NOTA, XAER_INVAL, or XAER_PROTO.
return
A value indicating the resource manager's vote on the outcome of the transaction. The possible values are: XA_RDONLY or XA_OK. If the resource manager wants to roll back the transaction, it should do so by raising an appropriate XAException in the prepare method.
public javax.transaction.xa.Xid[] recover(int flag)
Obtains a list of prepared transaction branches from a resource manager. The transaction manager calls this method during recovery to obtain the list of transaction branches that are currently in prepared or heuristically completed states.
param
flag One of TMSTARTRSCAN, TMENDRSCAN, TMNOFLAGS. TMNOFLAGS must be used when no other flags are set in the parameter.
exception
XAException An error has occurred. Possible values are XAER_RMERR, XAER_RMFAIL, XAER_INVAL, and XAER_PROTO.
return
The resource manager returns zero or more XIDs of the transaction branches that are currently in a prepared or heuristically completed state. If an error occurs during the operation, the resource manager should throw the appropriate XAException.
public void rollback(javax.transaction.xa.Xid xid)
Informs the resource manager to roll back work done on behalf of a transaction branch.
param
xid A global transaction identifier.
exception
XAException An error has occurred. Possible XAExceptions are XA_HEURHAZ, XA_HEURCOM, XA_HEURRB, XA_HEURMIX, XAER_RMERR, XAER_RMFAIL, XAER_NOTA, XAER_INVAL, or XAER_PROTO.
If the transaction branch is already marked rollback-only the resource manager may throw one of the XA_RB* exceptions. Upon return, the resource manager has rolled back the branch's work and has released all held resources.
public boolean setTransactionTimeout(int seconds)
Sets the current transaction timeout value for this XAResource instance. Once set, this timeout value is effective until setTransactionTimeout is invoked again with a different value. To reset the timeout value to the default value used by the resource manager, set the value to zero. If the timeout operation is performed successfully, the method returns true; otherwise false. If a resource manager does not support explicitly setting the transaction timeout value, this method returns false.
param
seconds The transaction timeout value in seconds.
return
true if the transaction timeout value is set successfully; otherwise false.
exception
XAException An error has occurred. Possible exception values are XAER_RMERR, XAER_RMFAIL, or XAER_INVAL.
public void start(javax.transaction.xa.Xid xid, int flags)
Starts work on behalf of a transaction branch specified in xid. If TMJOIN is specified, the start applies to joining a transaction previously seen by the resource manager. If TMRESUME is specified, the start applies to resuming a suspended transaction specified in the parameter xid. If neither TMJOIN nor TMRESUME is specified and the transaction specified by xid has previously been seen by the resource manager, the resource manager throws the XAException exception with XAER_DUPID error code.
param
xid A global transaction identifier to be associated with the resource.
param
flags One of TMNOFLAGS, TMJOIN, or TMRESUME.
exception
XAException An error has occurred. Possible exceptions are XA_RB*, XAER_RMERR, XAER_RMFAIL, XAER_DUPID, XAER_OUTSIDE, XAER_NOTA, XAER_INVAL, or XAER_PROTO.