//jTDS JDBC Driver for Microsoft SQL Server and Sybase
//Copyright (C) 2004 The jTDS Project
//
//This library is free software; you can redistribute it and/or
//modify it under the terms of the GNU Lesser General Public
//License as published by the Free Software Foundation; either
//version 2.1 of the License, or (at your option) any later version.
//
//This library is distributed in the hope that it will be useful,
//but WITHOUT ANY WARRANTY; without even the implied warranty of
//MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
//Lesser General Public License for more details.
//
//You should have received a copy of the GNU Lesser General Public
//License along with this library; if not, write to the Free Software
//Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
//
package net.sourceforge.jtds.jdbc;
import java.sql.Connection;
import java.sql.SQLException;
import javax.transaction.xa.XAException;
import javax.transaction.xa.XAResource;
import javax.transaction.xa.Xid;
import net.sourceforge.jtds.jdbcx.JtdsXid;
import net.sourceforge.jtds.util.Logger;
/**
* This class contains static utility methods used to implement distributed transactions.
* For SQL Server 2000 the driver can provide true distributed transactions provided that
* the external stored procedure in JtdsXA.dll is installed. For other types of server
* only an emulation is available at this stage.
*/
public class XASupport {
/**
* The Resource Manager ID allocated by jTDS
*/
private static final int XA_RMID = 1;
/**
* xa_open login string unique to jTDS.
*/
private static final String TM_ID = "TM=JTDS,RmRecoveryGuid=434CDE1A-F747-4942-9584-04937455CAB4";
//
// XA Switch constants
//
private static final int XA_OPEN = 1;
private static final int XA_CLOSE = 2;
private static final int XA_START = 3;
private static final int XA_END = 4;
private static final int XA_ROLLBACK = 5;
private static final int XA_PREPARE = 6;
private static final int XA_COMMIT = 7;
private static final int XA_RECOVER = 8;
private static final int XA_FORGET = 9;
private static final int XA_COMPLETE = 10;
/**
* Set this field to 1 to enable XA tracing.
*/
private static final int XA_TRACE = 0;
//
// ----- XA support routines -----
//
/**
* Invoke the xa_open routine on the SQL Server.
*
* @param connection the parent XAConnection object
* @return the XA connection ID allocated by xp_jtdsxa
*/
public static int xa_open(Connection connection)
throws SQLException {
JtdsConnection con = (JtdsConnection)connection;
if (con.isXaEmulation()) {
//
// Emulate xa_open method
//
Logger.println("xa_open: emulating distributed transaction support");
if (con.getXid() != null) {
throw new SQLException(
Messages.get("error.xasupport.activetran", "xa_open"),
"HY000");
}
con.setXaState(XA_OPEN);
return 0;
}
//
// Execute xa_open via MSDTC
//
// Check that we are using SQL Server 2000+
//
if (((JtdsConnection) connection).getServerType() != Driver.SQLSERVER
|| ((JtdsConnection) connection).getTdsVersion() < Driver.TDS80) {
throw new SQLException(Messages.get("error.xasupport.nodist"), "HY000");
}
Logger.println("xa_open: Using SQL2000 MSDTC to support distributed transactions");
//
// OK Now invoke extended stored procedure to register this connection.
//
int args[] = new int[5];
args[1] = XA_OPEN;
args[2] = XA_TRACE;
args[3] = XA_RMID;
args[4] = XAResource.TMNOFLAGS;
byte[][] id;
id = ((JtdsConnection) connection).sendXaPacket(args, TM_ID.getBytes());
if (args[0] != XAResource.XA_OK
|| id == null
|| id[0] == null
|| id[0].length != 4) {
throw new SQLException(
Messages.get("error.xasupport.badopen"), "HY000");
}
return (id[0][0] & 0xFF) |
((id[0][1] & 0xFF) << 8) |
((id[0][2] & 0xFF) << 16) |
((id[0][3] & 0xFF) << 24);
}
/**
* Invoke the xa_close routine on the SQL Server.
*
* @param connection JDBC Connection to be enlisted in the transaction
* @param xaConId the connection ID allocated by the server
*/
public static void xa_close(Connection connection, int xaConId)
throws SQLException {
JtdsConnection con = (JtdsConnection)connection;
if (con.isXaEmulation()) {
//
// Emulate xa_close method
//
con.setXaState(0);
if (con.getXid() != null) {
con.setXid(null);
try {
con.rollback();
} catch(SQLException e) {
Logger.println("xa_close: rollback() returned " + e);
}
try {
con.setAutoCommit(true);
} catch(SQLException e) {
Logger.println("xa_close: setAutoCommit() returned " + e);
}
throw new SQLException(
Messages.get("error.xasupport.activetran", "xa_close"),
"HY000");
}
return;
}
//
// Execute xa_close via MSDTC
//
int args[] = new int[5];
args[1] = XA_CLOSE;
args[2] = xaConId;
args[3] = XA_RMID;
args[4] = XAResource.TMNOFLAGS;
((JtdsConnection) connection).sendXaPacket(args, TM_ID.getBytes());
}
/**
* Invoke the xa_start routine on the SQL Server.
*
* @param connection JDBC Connection to be enlisted in the transaction
* @param xaConId the connection ID allocated by the server
* @param xid the XA Transaction ID object
* @param flags XA Flags for start command
* @exception javax.transaction.xa.XAException
* if an error condition occurs
*/
public static void xa_start(Connection connection, int xaConId, Xid xid, int flags)
throws XAException {
JtdsConnection con = (JtdsConnection)connection;
if (con.isXaEmulation()) {
//
// Emulate xa_start method
//
JtdsXid lxid = new JtdsXid(xid);
if (con.getXaState() == 0) {
// Connection not opened
raiseXAException(XAException.XAER_PROTO);
}
JtdsXid tran = (JtdsXid)con.getXid();
if (tran != null) {
if (tran.equals(lxid)) {
raiseXAException(XAException.XAER_DUPID);
} else {
raiseXAException(XAException.XAER_PROTO);
}
}
if (flags != XAResource.TMNOFLAGS) {
// TMJOIN and TMRESUME cannot be supported
raiseXAException(XAException.XAER_INVAL);
}
try {
connection.setAutoCommit(false);
} catch (SQLException e) {
raiseXAException(XAException.XAER_RMERR);
}
con.setXid(lxid);
con.setXaState(XA_START);
return;
}
//
// Execute xa_start via MSDTC
//
int args[] = new int[5];
args[1] = XA_START;
args[2] = xaConId;
args[3] = XA_RMID;
args[4] = flags;
byte[][] cookie;
try {
cookie = ((JtdsConnection) connection).sendXaPacket(args, toBytesXid(xid));
if (args[0] == XAResource.XA_OK && cookie != null) {
((JtdsConnection) connection).enlistConnection(cookie[0]);
}
} catch (SQLException e) {
raiseXAException(e);
}
if (args[0] != XAResource.XA_OK) {
raiseXAException(args[0]);
}
}
/**
* Invoke the xa_end routine on the SQL Server.
*
* @param connection JDBC Connection enlisted in the transaction
* @param xaConId the connection ID allocated by the server
* @param xid the XA Transaction ID object
* @param flags XA Flags for start command
* @exception javax.transaction.xa.XAException
* if an error condition occurs
*/
public static void xa_end(Connection connection, int xaConId, Xid xid, int flags)
throws XAException {
JtdsConnection con = (JtdsConnection)connection;
if (con.isXaEmulation()) {
//
// Emulate xa_end method
//
JtdsXid lxid = new JtdsXid(xid);
if (con.getXaState() != XA_START) {
// Connection not started
raiseXAException(XAException.XAER_PROTO);
}
JtdsXid tran = (JtdsXid)con.getXid();
if (tran == null || !tran.equals(lxid)) {
raiseXAException(XAException.XAER_NOTA);
}
if (flags != XAResource.TMSUCCESS &&
flags != XAResource.TMFAIL) {
// TMSUSPEND and TMMIGRATE cannot be supported
raiseXAException(XAException.XAER_INVAL);
}
con.setXaState(XA_END);
return;
}
//
// Execute xa_end via MSDTC
//
int args[] = new int[5];
args[1] = XA_END;
args[2] = xaConId;
args[3] = XA_RMID;
args[4] = flags;
try {
((JtdsConnection) connection).sendXaPacket(args, toBytesXid(xid));
((JtdsConnection) connection).enlistConnection(null);
} catch (SQLException e) {
raiseXAException(e);
}
if (args[0] != XAResource.XA_OK) {
raiseXAException(args[0]);
}
}
/**
* Invoke the xa_prepare routine on the SQL Server.
*
* @param connection JDBC Connection enlisted in the transaction.
* @param xaConId The connection ID allocated by the server.
* @param xid The XA Transaction ID object.
* @return prepare status (XA_OK or XA_RDONLY) as an <code>int</code>.
* @exception javax.transaction.xa.XAException
* if an error condition occurs
*/
public static int xa_prepare(Connection connection, int xaConId, Xid xid)
throws XAException {
JtdsConnection con = (JtdsConnection)connection;
if (con.isXaEmulation()) {
//
// Emulate xa_prepare method
// In emulation mode this is essentially a noop as we
// are not able to offer true two phase commit.
//
JtdsXid lxid = new JtdsXid(xid);
if (con.getXaState() != XA_END) {
// Connection not ended
raiseXAException(XAException.XAER_PROTO);
}
JtdsXid tran = (JtdsXid)con.getXid();
if (tran == null || !tran.equals(lxid)) {
raiseXAException(XAException.XAER_NOTA);
}
con.setXaState(XA_PREPARE);
Logger.println("xa_prepare: Warning: Two phase commit not available in XA emulation mode.");
return XAResource.XA_OK;
}
//
// Execute xa_prepare via MSDTC
//
int args[] = new int[5];
args[1] = XA_PREPARE;
args[2] = xaConId;
args[3] = XA_RMID;
args[4] = XAResource.TMNOFLAGS;
try {
((JtdsConnection) connection).sendXaPacket(args, toBytesXid(xid));
} catch (SQLException e) {
raiseXAException(e);
}
if (args[0] != XAResource.XA_OK && args[0] != XAResource.XA_RDONLY) {
raiseXAException(args[0]);
}
return args[0];
}
/**
* Invoke the xa_commit routine on the SQL Server.
*
* @param connection JDBC Connection enlisted in the transaction
* @param xaConId the connection ID allocated by the server
* @param xid the XA Transaction ID object
* @param onePhase <code>true</code> if single phase commit required
* @exception javax.transaction.xa.XAException
* if an error condition occurs
*/
public static void xa_commit(Connection connection, int xaConId, Xid xid, boolean onePhase)
throws XAException {
JtdsConnection con = (JtdsConnection)connection;
if (con.isXaEmulation()) {
//
// Emulate xa_commit method
//
JtdsXid tran = (JtdsXid)con.getXid();
/*
* if tran == null, we assume recovery
*/
if (tran == null)
{
try
{
connection.setAutoCommit(false);
}
catch (SQLException e)
{
raiseXAException(XAException.XAER_RMERR);
}
}
else
{
if (con.getXaState() != XA_END && con.getXaState() != XA_PREPARE)
{
// Connection not ended or prepared
raiseXAException(XAException.XAER_PROTO);
}
JtdsXid lxid = new JtdsXid(xid);
if (!tran.equals(lxid))
{
raiseXAException(XAException.XAER_NOTA);
}
}
con.setXid(null);
try {
con.commit();
} catch (SQLException e) {
raiseXAException(e);
} finally {
try {
con.setAutoCommit(true);
} catch(SQLException e) {
Logger.println("xa_close: setAutoCommit() returned " + e);
}
con.setXaState(XA_OPEN);
}
return;
}
//
// Execute xa_commit via MSDTC
//
int args[] = new int[5];
args[1] = XA_COMMIT;
args[2] = xaConId;
args[3] = XA_RMID;
args[4] = (onePhase) ? XAResource.TMONEPHASE : XAResource.TMNOFLAGS;
try {
((JtdsConnection) connection).sendXaPacket(args, toBytesXid(xid));
} catch (SQLException e) {
raiseXAException(e);
}
if (args[0] != XAResource.XA_OK) {
raiseXAException(args[0]);
}
}
/**
* Invoke the xa_rollback routine on the SQL Server.
*
* @param connection JDBC Connection enlisted in the transaction
* @param xaConId the connection ID allocated by the server
* @param xid the XA Transaction ID object
* @exception javax.transaction.xa.XAException
* if an error condition occurs
*/
public static void xa_rollback(Connection connection, int xaConId, Xid xid)
throws XAException {
JtdsConnection con = (JtdsConnection)connection;
if (con.isXaEmulation()) {
//
// Emulate xa_rollback method
//
JtdsXid lxid = new JtdsXid(xid);
if (con.getXaState()!= XA_END && con.getXaState() != XA_PREPARE) {
// Connection not ended
raiseXAException(XAException.XAER_PROTO);
}
JtdsXid tran = (JtdsXid)con.getXid();
if (tran == null || !tran.equals(lxid)) {
raiseXAException(XAException.XAER_NOTA);
}
con.setXid(null);
try {
con.rollback();
} catch (SQLException e) {
raiseXAException(e);
} finally {
try {
con.setAutoCommit(true);
} catch(SQLException e) {
Logger.println("xa_close: setAutoCommit() returned " + e);
}
con.setXaState(XA_OPEN);
}
return;
}
//
// Execute xa_rollback via MSDTC
//
int args[] = new int[5];
args[1] = XA_ROLLBACK;
args[2] = xaConId;
args[3] = XA_RMID;
args[4] = XAResource.TMNOFLAGS;
try {
((JtdsConnection) connection).sendXaPacket(args, toBytesXid(xid));
} catch (SQLException e) {
raiseXAException(e);
}
if (args[0] != XAResource.XA_OK) {
raiseXAException(args[0]);
}
}
/**
* Invoke the xa_recover routine on the SQL Server.
* <p/>
* This version of xa_recover will return all XIDs on the first call.
*
* @param connection JDBC Connection enlisted in the transaction
* @param xaConId the connection ID allocated by the server
* @param flags XA Flags for start command
* @return transactions to recover as a <code>Xid[]</code>
* @exception javax.transaction.xa.XAException
* if an error condition occurs
*/
public static Xid[] xa_recover(Connection connection, int xaConId, int flags)
throws XAException {
JtdsConnection con = (JtdsConnection)connection;
if (con.isXaEmulation()) {
//
// Emulate xa_recover method
//
// There is no state available all uncommited transactions
// will have been rolled back by the server.
if (flags != XAResource.TMSTARTRSCAN &&
flags != XAResource.TMENDRSCAN &&
flags != ( XAResource.TMSTARTRSCAN | XAResource.TMENDRSCAN ) &&
flags != XAResource.TMNOFLAGS) {
raiseXAException(XAException.XAER_INVAL);
}
return new JtdsXid[0];
}
//
// Execute xa_recover via MSDTC
//
int args[] = new int[5];
args[1] = XA_RECOVER;
args[2] = xaConId;
args[3] = XA_RMID;
args[4] = XAResource.TMNOFLAGS;
Xid[] list = null;
if (flags != XAResource.TMSTARTRSCAN) {
return new JtdsXid[0];
}
try {
byte[][] buffer = ((JtdsConnection) connection).sendXaPacket(args, null);
if (args[0] >= 0) {
int n = buffer.length;
list = new JtdsXid[n];
for (int i = 0; i < n; i++) {
list[i] = new JtdsXid(buffer[i], 0);
}
}
} catch (SQLException e) {
raiseXAException(e);
}
if (args[0] < 0) {
raiseXAException(args[0]);
}
if (list == null) {
list = new JtdsXid[0];
}
return list;
}
/**
* Invoke the xa_forget routine on the SQL Server.
*
* @param connection JDBC Connection enlisted in the transaction
* @param xaConId the connection ID allocated by the server
* @param xid the XA Transaction ID object
* @exception javax.transaction.xa.XAException
* if an error condition occurs
*/
public static void xa_forget(Connection connection, int xaConId, Xid xid)
throws XAException {
JtdsConnection con = (JtdsConnection)connection;
if (con.isXaEmulation()) {
//
// Emulate xa_forget method
//
JtdsXid lxid = new JtdsXid(xid);
JtdsXid tran = (JtdsXid)con.getXid();
/*
* if tran == null, we assume recovery
*/
if (tran != null && !tran.equals(lxid)) {
raiseXAException(XAException.XAER_NOTA);
}
if (con.getXaState() != XA_END && con.getXaState() != XA_PREPARE) {
// Connection not ended
raiseXAException(XAException.XAER_PROTO);
}
con.setXid(null);
try {
con.rollback();
} catch (SQLException e) {
raiseXAException(e);
} finally {
try {
con.setAutoCommit(true);
} catch(SQLException e) {
Logger.println("xa_close: setAutoCommit() returned " + e);
}
con.setXaState(XA_OPEN);
}
return;
}
//
// Execute xa_forget via MSDTC
//
int args[] = new int[5];
args[1] = XA_FORGET;
args[2] = xaConId;
args[3] = XA_RMID;
args[4] = XAResource.TMNOFLAGS;
try {
((JtdsConnection) connection).sendXaPacket(args, toBytesXid(xid));
} catch (SQLException e) {
raiseXAException(e);
}
if (args[0] != XAResource.XA_OK) {
raiseXAException(args[0]);
}
}
/**
* Construct and throw an <code>XAException</code> with an explanatory message derived from the
* <code>SQLException</code> and the XA error code set to <code>XAER_RMFAIL</code>.
*
* @param sqle The SQLException.
* @exception javax.transaction.xa.XAException
* exception derived from the code>SQLException</code>
*/
public static void raiseXAException(SQLException sqle)
throws XAException {
XAException e = new XAException(sqle.getMessage());
e.errorCode = XAException.XAER_RMFAIL;
Logger.println("XAException: " + e.getMessage());
throw e;
}
/**
* Construct and throw an <code>XAException</code> with an explanatory message and the XA error code set.
*
* @param errorCode the XA Error code
* @exception javax.transaction.xa.XAException
* the constructed exception
*/
public static void raiseXAException(int errorCode)
throws XAException {
String err = "xaerunknown";
switch (errorCode) {
case XAException.XA_RBROLLBACK:
err = "xarbrollback";
break;
case XAException.XA_RBCOMMFAIL:
err = "xarbcommfail";
break;
case XAException.XA_RBDEADLOCK:
err = "xarbdeadlock";
break;
case XAException.XA_RBINTEGRITY:
err = "xarbintegrity";
break;
case XAException.XA_RBOTHER:
err = "xarbother";
break;
case XAException.XA_RBPROTO:
err = "xarbproto";
break;
case XAException.XA_RBTIMEOUT:
err = "xarbtimeout";
break;
case XAException.XA_RBTRANSIENT:
err = "xarbtransient";
break;
case XAException.XA_NOMIGRATE:
err = "xanomigrate";
break;
case XAException.XA_HEURHAZ:
err = "xaheurhaz";
break;
case XAException.XA_HEURCOM:
err = "xaheurcom";
break;
case XAException.XA_HEURRB:
err = "xaheurrb";
break;
case XAException.XA_HEURMIX:
err = "xaheurmix";
break;
case XAException.XA_RETRY:
err = "xaretry";
break;
case XAException.XA_RDONLY:
err = "xardonly";
break;
case XAException.XAER_ASYNC:
err = "xaerasync";
break;
case XAException.XAER_NOTA:
err = "xaernota";
break;
case XAException.XAER_INVAL:
err = "xaerinval";
break;
case XAException.XAER_PROTO:
err = "xaerproto";
break;
case XAException.XAER_RMERR:
err = "xaerrmerr";
break;
case XAException.XAER_RMFAIL:
err = "xaerrmfail";
break;
case XAException.XAER_DUPID:
err = "xaerdupid";
break;
case XAException.XAER_OUTSIDE:
err = "xaeroutside";
break;
}
XAException e = new XAException(Messages.get("error.xaexception." + err));
e.errorCode = errorCode;
Logger.println("XAException: " + e.getMessage());
throw e;
}
// ------------- Private methods ---------
/**
* Format an XA transaction ID into a 140 byte array.
*
* @param xid the XA transaction ID
* @return the formatted ID as a <code>byte[]</code>
*/
private static byte[] toBytesXid(Xid xid) {
byte[] buffer = new byte[12 +
xid.getGlobalTransactionId().length +
xid.getBranchQualifier().length];
int fmt = xid.getFormatId();
buffer[0] = (byte) fmt;
buffer[1] = (byte) (fmt >> 8);
buffer[2] = (byte) (fmt >> 16);
buffer[3] = (byte) (fmt >> 24);
buffer[4] = (byte) xid.getGlobalTransactionId().length;
buffer[8] = (byte) xid.getBranchQualifier().length;
System.arraycopy(xid.getGlobalTransactionId(), 0, buffer, 12, buffer[4]);
System.arraycopy(xid.getBranchQualifier(), 0, buffer, 12 + buffer[4], buffer[8]);
return buffer;
}
private XASupport() {
// Prevent an instance of this class being created.
}
}