Class PGXAConnection

  • All Implemented Interfaces:
    javax.sql.PooledConnection, javax.sql.XAConnection, javax.transaction.xa.XAResource

    public class PGXAConnection
    extends PGPooledConnection
    implements javax.sql.XAConnection, javax.transaction.xa.XAResource

    The PostgreSQL implementation of XAResource.

    This implementation doesn't support transaction interleaving (see JTA specification, section 3.4.4) and suspend/resume.

    Two-phase commit requires PostgreSQL server version 8.1 or higher.

    Author:
    Heikki Linnakangas (heikki.linnakangas@iki.fi)
    • Field Summary

      • Fields inherited from interface javax.transaction.xa.XAResource

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

      • PGXAConnection

        public PGXAConnection​(BaseConnection conn)
                       throws java.sql.SQLException
        Throws:
        java.sql.SQLException
    • Method Detail

      • getConnection

        public java.sql.Connection getConnection()
                                          throws java.sql.SQLException
        XAConnection interface.
        Specified by:
        getConnection in interface javax.sql.PooledConnection
        Overrides:
        getConnection in class PGPooledConnection
        Throws:
        java.sql.SQLException
      • getXAResource

        public javax.transaction.xa.XAResource getXAResource()
        Specified by:
        getXAResource in interface javax.sql.XAConnection
      • start

        public void start​(javax.transaction.xa.Xid xid,
                          int flags)
                   throws javax.transaction.xa.XAException

        Preconditions:

        1. Flags must be one of TMNOFLAGS, TMRESUME or TMJOIN
        2. xid != null
        3. Connection must not be associated with a transaction
        4. The TM hasn't seen the xid before

        Implementation deficiency preconditions:

        1. TMRESUME not supported.
        2. If flags is TMJOIN, we must be in ended state, and xid must be the current transaction
        3. Unless flags is TMJOIN, previous transaction using the connection must be committed or prepared or rolled back

        Postconditions:

        1. Connection is associated with the transaction
        Specified by:
        start in interface javax.transaction.xa.XAResource
        Throws:
        javax.transaction.xa.XAException
      • end

        public void end​(javax.transaction.xa.Xid xid,
                        int flags)
                 throws javax.transaction.xa.XAException

        Preconditions:

        1. Flags is one of TMSUCCESS, TMFAIL, TMSUSPEND
        2. xid != null
        3. Connection is associated with transaction xid

        Implementation deficiency preconditions:

        1. Flags is not TMSUSPEND

        Postconditions:

        1. Connection is disassociated from the transaction.
        Specified by:
        end in interface javax.transaction.xa.XAResource
        Throws:
        javax.transaction.xa.XAException
      • prepare

        public int prepare​(javax.transaction.xa.Xid xid)
                    throws javax.transaction.xa.XAException

        Prepares transaction. Preconditions:

        1. xid != null
        2. xid is in ended state

        Implementation deficiency preconditions:

        1. xid was associated with this connection

        Postconditions:

        1. Transaction is prepared
        Specified by:
        prepare in interface javax.transaction.xa.XAResource
        Throws:
        javax.transaction.xa.XAException
      • recover

        public javax.transaction.xa.Xid[] recover​(int flag)
                                           throws javax.transaction.xa.XAException

        Recovers transaction. Preconditions:

        1. flag must be one of TMSTARTRSCAN, TMENDRSCAN, TMNOFLAGS or TMSTARTTRSCAN | TMENDRSCAN
        2. If flag isn't TMSTARTRSCAN or TMSTARTRSCAN | TMENDRSCAN, a recovery scan must be in progress

        Postconditions:

        1. list of prepared xids is returned
        Specified by:
        recover in interface javax.transaction.xa.XAResource
        Throws:
        javax.transaction.xa.XAException
      • rollback

        public void rollback​(javax.transaction.xa.Xid xid)
                      throws javax.transaction.xa.XAException

        Preconditions:

        1. xid is known to the RM or it's in prepared state

        Implementation deficiency preconditions:

        1. xid must be associated with this connection if it's not in prepared state.

        Postconditions:

        1. Transaction is rolled back and disassociated from connection
        Specified by:
        rollback in interface javax.transaction.xa.XAResource
        Throws:
        javax.transaction.xa.XAException
      • commit

        public void commit​(javax.transaction.xa.Xid xid,
                           boolean onePhase)
                    throws javax.transaction.xa.XAException
        Specified by:
        commit in interface javax.transaction.xa.XAResource
        Throws:
        javax.transaction.xa.XAException
      • isSameRM

        public boolean isSameRM​(javax.transaction.xa.XAResource xares)
                         throws javax.transaction.xa.XAException
        Specified by:
        isSameRM in interface javax.transaction.xa.XAResource
        Throws:
        javax.transaction.xa.XAException
      • forget

        public void forget​(javax.transaction.xa.Xid xid)
                    throws javax.transaction.xa.XAException
        Does nothing, since we don't do heuristics.
        Specified by:
        forget in interface javax.transaction.xa.XAResource
        Throws:
        javax.transaction.xa.XAException
      • getTransactionTimeout

        public int getTransactionTimeout()
        We don't do transaction timeouts. Just returns 0.
        Specified by:
        getTransactionTimeout in interface javax.transaction.xa.XAResource
      • setTransactionTimeout

        public boolean setTransactionTimeout​(int seconds)
        We don't do transaction timeouts. Returns false.
        Specified by:
        setTransactionTimeout in interface javax.transaction.xa.XAResource