package com.arjuna.wst11.stub;
import com.arjuna.wst.*;
import com.arjuna.wst.stub.SystemCommunicationException;
import com.arjuna.wst11.messaging.engines.CoordinatorEngine;
import com.arjuna.wst11.messaging.CoordinatorProcessorImpl;
import com.arjuna.webservices11.wsat.State;
import com.arjuna.webservices11.wsat.processors.CoordinatorProcessor;
import com.arjuna.webservices11.util.StreamHelper;
import com.arjuna.webservices.soap.SoapUtils;
import com.arjuna.webservices.logging.WSTLogger;
import com.arjuna.ats.arjuna.state.OutputObjectState;
import com.arjuna.ats.arjuna.state.InputObjectState;
import javax.xml.namespace.QName;
import javax.xml.stream.XMLStreamWriter;
import javax.xml.stream.XMLStreamReader;
import javax.xml.ws.wsaddressing.W3CEndpointReference;
import javax.xml.transform.stream.StreamSource;
import java.io.StringWriter;
import java.io.StringReader;
public class ParticipantStub implements Participant, PersistableParticipant
{
private static final QName QNAME_TWO_PC_PARTICIPANT = new QName("twoPCParticipant") ;
private CoordinatorEngine coordinator ;
public ParticipantStub(final String id, final boolean durable, final W3CEndpointReference twoPCParticipant)
throws Exception
{
// id will be supplied as null during recovery in which case we can delay creation
// of the coordinator until restore_state is called
if (id != null) {
coordinator = new CoordinatorEngine(id, durable, twoPCParticipant) ;
}
}
public Vote prepare()
throws WrongStateException, SystemException
{
/*
* null - aborted or read only
* Active - illegal state
* Preparing - no answer
* Prepared - illegal state
* PreparedSuccess - prepared
* Committing - illegal state
* Aborting - aborting
*/
final State state = coordinator.prepare() ;
if (state == State.STATE_PREPARED_SUCCESS)
{
return new Prepared() ;
}
else if (state == State.STATE_ABORTING)
{
return new Aborted() ;
}
else if (state == null)
{
if (coordinator.isReadOnly())
{
return new ReadOnly() ;
}
else
{
return new Aborted() ;
}
}
else if (state == State.STATE_PREPARING)
{
// typically means no response from the remote end.
// throw a comm exception to distinguish this case from the
// one where the remote end itself threw a SystemException.
throw new SystemCommunicationException() ;
}
else
{
throw new WrongStateException() ;
}
}
public void commit()
throws WrongStateException, SystemException
{
/*
* null - committed
* Active - illegal state
* Preparing - illegal state
* Prepared - illegal state
* PreparedSuccess - illegal state
* Committing - no response
* Aborting - illegal state
*/
final State state = coordinator.commit() ;
if (state != null)
{
if (state == State.STATE_COMMITTING)
{
// typically means no response from the remote end.
// throw a comm exception to distinguish this case from the
// one where the remote end itself threw a SystemException.
throw new SystemCommunicationException();
}
else
{
throw new WrongStateException() ;
}
}
}
public void rollback()
throws WrongStateException, SystemException
{
/*
* null - aborted
* Active - illegal state
* Preparing - illegal state
* Prepared - illegal state
* PreparedSuccess - illegal state
* Committing - illegal state
* Aborting - no response
*/
final State state = coordinator.rollback() ;
if (state != null)
{
if (state == State.STATE_ABORTING)
{
throw new SystemCommunicationException() ;
}
else
{
throw new WrongStateException() ;
}
}
}
public void unknown()
throws SystemException
{
error() ;
}
public void error()
throws SystemException
{
try
{
rollback() ;
}
catch (final WrongStateException wse) {} // ignore
}
/**
* @message com.arjuna.wst11.stub.ParticipantStub_1 [com.arjuna.wst11.stub.ParticipantStub_1] - Error persisting participant state
*/
public boolean saveState(final OutputObjectState oos)
{
try
{
oos.packString(coordinator.getId()) ;
oos.packBoolean(coordinator.isDurable()) ;
State state = coordinator.getState();
// participants in the heuristic list may get saved in any state
if (state == State.STATE_ACTIVE) {
oos.packInt(0);
} else if (state == State.STATE_PREPARING) {
oos.packInt(1);
} else if (state == State.STATE_PREPARED ||
state == State.STATE_PREPARED_SUCCESS) {
oos.packInt(2);
} else if (state == State.STATE_ABORTING) {
oos.packInt(3);
} else { // COMMITTING or none
oos.packInt(4);
}
// n.b. just use toString() for the endpoint -- it uses the writeTo() method which calls a suitable marshaller
final StringWriter sw = new StringWriter() ;
final XMLStreamWriter writer = SoapUtils.getXMLStreamWriter(sw) ;
StreamHelper.writeStartElement(writer, QNAME_TWO_PC_PARTICIPANT) ;
String eprefText = coordinator.getParticipant().toString();
writer.writeCData(eprefText);
StreamHelper.writeEndElement(writer, null, null) ;
writer.close() ;
sw.close();
String tmp = writer.toString();
String swString = sw.toString();
oos.packString(swString) ;
return true ;
}
catch (final Throwable th)
{
WSTLogger.arjLoggerI18N.error("com.arjuna.wst11.stub.ParticipantStub_1", th) ;
return false ;
}
}
/**
* @message com.arjuna.wst11.stub.ParticipantStub_2 [com.arjuna.wst11.stub.ParticipantStub_2] - Error restoring participant state
*/
public boolean restoreState(final InputObjectState ios)
{
State state;
try
{
final String id = ios.unpackString() ;
final boolean durable = ios.unpackBoolean() ;
final int stateTag = ios.unpackInt();
switch (stateTag)
{
case 0:
state = State.STATE_ACTIVE;
break;
case 1:
state = State.STATE_PREPARING;
break;
case 2:
state = State.STATE_PREPARED_SUCCESS;
break;
case 3:
state = State.STATE_ABORTING;
break;
default:
state = State.STATE_COMMITTING;
break;
}
final String eprValue = ios.unpackString() ;
// this should successfully reverse the save process
final XMLStreamReader reader = SoapUtils.getXMLStreamReader(new StringReader(eprValue)) ;
StreamHelper.checkNextStartTag(reader, QNAME_TWO_PC_PARTICIPANT) ;
String eprefText = reader.getElementText();
StreamSource source = new StreamSource(new StringReader(eprefText));
final W3CEndpointReference endpointReference = new W3CEndpointReference(source);
// if we already have a coordinator from a previous recovery scan or because
// we had a heuristic outcoe then reuse it with luck it will have been committed
// or aborted between the last scan and this one
// note that whatever happens it will not have been removed from the table
// because it is marked as recovered
coordinator = (CoordinatorEngine)CoordinatorProcessorImpl.getProcessor().getCoordinator(id);
if (coordinator == null) {
// no entry found so recreate one with the saved state
coordinator = new CoordinatorEngine(id, durable, endpointReference, true, state) ;
}
return true ;
}
catch (final Throwable th)
{
WSTLogger.arjLoggerI18N.error("com.arjuna.wst11.stub.ParticipantStub_2", th) ;
return false ;
}
}
}