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public interface: XAResource [javadoc | source]

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.

Field 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. 
Method from javax.transaction.xa.XAResource Summary:
commit,   end,   forget,   getTransactionTimeout,   isSameRM,   prepare,   recover,   rollback,   setTransactionTimeout,   start
Method from javax.transaction.xa.XAResource Detail:
 public  void commit(Xid xid,
    boolean onePhase) throws XAException
    Commits the global transaction specified by xid.
 public  void end(Xid xid,
    int flags) throws XAException
    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.

 public  void forget(Xid xid) throws XAException
    Tells the resource manager to forget about a heuristically completed transaction branch.
 public int getTransactionTimeout() throws XAException
    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.
 public boolean isSameRM(XAResource xares) throws XAException
    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.
 public int prepare(Xid xid) throws XAException
    Ask the resource manager to prepare for a transaction commit of the transaction specified in xid.
 public Xid[] recover(int flag) throws XAException
    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.
 public  void rollback(Xid xid) throws XAException
    Informs the resource manager to roll back work done on behalf of a transaction branch.
 public boolean setTransactionTimeout(int seconds) throws XAException

    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.

 public  void start(Xid xid,
    int flags) throws XAException
    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.