/**
* Preconditions: 1. xid must be in prepared state in the server
*
* <p>Implementation deficiency preconditions: 1. Connection must be in idle state
*
* <p>Postconditions: 1. Transaction is committed
*/
private void commitPrepared(Xid xid) throws XAException {
try {
// Check preconditions. The connection mustn't be used for another
// other XA or local transaction, or the COMMIT PREPARED command
// would mess it up.
if (state != STATE_IDLE || conn.getTransactionState() != ProtocolConnection.TRANSACTION_IDLE)
throw new PGXAException(
GT.tr("Not implemented: 2nd phase commit must be issued using an idle connection"),
XAException.XAER_RMERR);
String s = RecoveredXid.xidToString(xid);
localAutoCommitMode = conn.getAutoCommit();
conn.setAutoCommit(true);
Statement stmt = conn.createStatement();
try {
stmt.executeUpdate("COMMIT PREPARED '" + s + "'");
} finally {
stmt.close();
conn.setAutoCommit(localAutoCommitMode);
}
} catch (SQLException ex) {
throw new PGXAException(
GT.tr("Error committing prepared transaction"), ex, XAException.XAER_RMERR);
}
}
/**
* Preconditions: 1. xid is known to the RM or it's in prepared state
*
* <p>Implementation deficiency preconditions: 1. xid must be associated with this connection if
* it's not in prepared state.
*
* <p>Postconditions: 1. Transaction is rolled back and disassociated from connection
*/
public void rollback(Xid xid) throws XAException {
if (logger.logDebug()) debug("rolling back xid = " + xid);
// We don't explicitly check precondition 1.
try {
if (currentXid != null && xid.equals(currentXid)) {
state = STATE_IDLE;
currentXid = null;
conn.rollback();
conn.setAutoCommit(localAutoCommitMode);
} else {
String s = RecoveredXid.xidToString(xid);
conn.setAutoCommit(true);
Statement stmt = conn.createStatement();
try {
stmt.executeUpdate("ROLLBACK PREPARED '" + s + "'");
} finally {
stmt.close();
}
}
} catch (SQLException ex) {
throw new PGXAException(
GT.tr("Error rolling back prepared transaction"), ex, XAException.XAER_RMERR);
}
}
/**
* Preconditions: 1. xid must in ended state.
*
* <p>Implementation deficiency preconditions: 1. this connection must have been used to run the
* transaction
*
* <p>Postconditions: 1. Transaction is committed
*/
private void commitOnePhase(Xid xid) throws XAException {
try {
// Check preconditions
if (currentXid == null || !currentXid.equals(xid)) {
// In fact, we don't know if xid is bogus, or if it just wasn't associated with this
// connection.
// Assume it's our fault.
throw new PGXAException(
GT.tr(
"Not implemented: one-phase commit must be issued using the same connection that was used to start it"),
XAException.XAER_RMERR);
}
if (state != STATE_ENDED)
throw new PGXAException(GT.tr("commit called before end"), XAException.XAER_PROTO);
// Preconditions are met. Commit
state = STATE_IDLE;
currentXid = null;
conn.commit();
conn.setAutoCommit(localAutoCommitMode);
} catch (SQLException ex) {
throw new PGXAException(GT.tr("Error during one-phase commit"), ex, XAException.XAER_RMERR);
}
}
/**
* 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
*
* <p>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
*
* <p>Postconditions: 1. Connection is associated with the transaction
*/
public void start(Xid xid, int flags) throws XAException {
if (logger.logDebug()) debug("starting transaction xid = " + xid);
// Check preconditions
if (flags != XAResource.TMNOFLAGS && flags != XAResource.TMRESUME && flags != XAResource.TMJOIN)
throw new PGXAException(GT.tr("Invalid flags"), XAException.XAER_INVAL);
if (xid == null) throw new PGXAException(GT.tr("xid must not be null"), XAException.XAER_INVAL);
if (state == STATE_ACTIVE)
throw new PGXAException(
GT.tr("Connection is busy with another transaction"), XAException.XAER_PROTO);
// We can't check precondition 4 easily, so we don't. Duplicate xid will be catched in prepare
// phase.
// Check implementation deficiency preconditions
if (flags == TMRESUME)
throw new PGXAException(GT.tr("suspend/resume not implemented"), XAException.XAER_RMERR);
// It's ok to join an ended transaction. WebLogic does that.
if (flags == TMJOIN) {
if (state != STATE_ENDED)
throw new PGXAException(
GT.tr("Transaction interleaving not implemented"), XAException.XAER_RMERR);
if (!xid.equals(currentXid))
throw new PGXAException(
GT.tr("Transaction interleaving not implemented"), XAException.XAER_RMERR);
} else if (state == STATE_ENDED)
throw new PGXAException(
GT.tr("Transaction interleaving not implemented"), XAException.XAER_RMERR);
try {
localAutoCommitMode = conn.getAutoCommit();
conn.setAutoCommit(false);
} catch (SQLException ex) {
throw new PGXAException(GT.tr("Error disabling autocommit"), ex, XAException.XAER_RMERR);
}
// Preconditions are met, Associate connection with the transaction
state = STATE_ACTIVE;
currentXid = xid;
}
/**
* Preconditions: 1. xid != null 2. xid is in ended state
*
* <p>Implementation deficiency preconditions: 1. xid was associated with this connection
*
* <p>Postconditions: 1. Transaction is prepared
*/
public int prepare(Xid xid) throws XAException {
if (logger.logDebug()) debug("preparing transaction xid = " + xid);
// Check preconditions
if (!currentXid.equals(xid)) {
throw new PGXAException(
GT.tr(
"Not implemented: Prepare must be issued using the same connection that started the transaction"),
XAException.XAER_RMERR);
}
if (state != STATE_ENDED)
throw new PGXAException(GT.tr("Prepare called before end"), XAException.XAER_INVAL);
state = STATE_IDLE;
currentXid = null;
if (!conn.haveMinimumServerVersion("8.1"))
throw new PGXAException(
GT.tr("Server versions prior to 8.1 do not support two-phase commit."),
XAException.XAER_RMERR);
try {
String s = RecoveredXid.xidToString(xid);
Statement stmt = conn.createStatement();
try {
stmt.executeUpdate("PREPARE TRANSACTION '" + s + "'");
} finally {
stmt.close();
}
conn.setAutoCommit(localAutoCommitMode);
return XA_OK;
} catch (SQLException ex) {
throw new PGXAException(GT.tr("Error preparing transaction"), ex, XAException.XAER_RMERR);
}
}
