package com.arjuna.wst11.messaging.engines;
import com.arjuna.webservices.SoapFault;
import com.arjuna.webservices.SoapFaultType;
import com.arjuna.webservices.logging.WSTLogger;
import com.arjuna.webservices.util.TransportTimer;
import com.arjuna.webservices11.SoapFault11;
import com.arjuna.webservices11.wsaddr.AddressingHelper;
import org.jboss.ws.api.addressing.MAP;
import com.arjuna.webservices11.wsarj.ArjunaContext;
import com.arjuna.webservices11.wsarj.InstanceIdentifier;
import com.arjuna.webservices11.wsat.CoordinatorInboundEvents;
import com.arjuna.webservices11.wsat.State;
import com.arjuna.webservices11.wsat.AtomicTransactionConstants;
import com.arjuna.webservices11.wsat.client.ParticipantClient;
import com.arjuna.webservices11.wsat.processors.CoordinatorProcessor;
import com.arjuna.wsc11.messaging.MessageId;
import org.oasis_open.docs.ws_tx.wsat._2006._06.Notification;
import javax.xml.namespace.QName;
import javax.xml.ws.wsaddressing.W3CEndpointReference;
import java.util.TimerTask;
/**
* The coordinator state engine
* @author kevin
*/
public class CoordinatorEngine implements CoordinatorInboundEvents
{
/**
* Flag indicating this is a coordinator for a durable participant.
*/
private final boolean durable ;
/**
* The coordinator id.
*/
private final String id ;
/**
* The instance identifier.
*/
private final InstanceIdentifier instanceIdentifier ;
/**
* The participant endpoint reference.
*/
private final W3CEndpointReference participant ;
/**
* The current state.
*/
private State state ;
/**
* The flag indicating that this coordinator has been recovered from the log.
*/
private boolean recovered ;
/**
* The flag indicating a read only response.
*/
private boolean readOnly ;
/**
* The associated timer task or null.
*/
private TimerTask timerTask ;
/**
* Construct the initial engine for the coordinator.
* @param id The coordinator id.
* @param durable true if the participant is durable, false if volatile.
* @param participant The participant endpoint reference.
*/
public CoordinatorEngine(final String id, final boolean durable, final W3CEndpointReference participant)
{
this(id, durable, participant, false, State.STATE_ACTIVE) ;
}
/**
* Construct the engine for the coordinator in a specified state.
* @param id The coordinator id.
* @param durable true if the participant is durable, false if volatile.
* @param participant The participant endpoint reference.
* @param state The initial state.
*/
public CoordinatorEngine(final String id, final boolean durable, final W3CEndpointReference participant, boolean recovered, final State state)
{
this.id = id ;
this.instanceIdentifier = new InstanceIdentifier(id) ;
this.durable = durable ;
this.participant = participant ;
this.state = state ;
this.recovered = recovered;
// unrecovered participants are always activated
// we only need to reactivate recovered participants which were successfully prepared
// any others will only have been saved because of a heuristic outcome e.g. a comms
// timeout at prepare will write a heuristic record for an ABORTED TX including a
// participant in state PREPARING. we can safely drop it since we implement presumed abort.
if (!recovered || state == State.STATE_PREPARED_SUCCESS) {
CoordinatorProcessor.getProcessor().activateCoordinator(this, id) ;
}
}
/**
* Handle the aborted event.
* @param aborted The aborted notification.
* @param map The addressing context.
* @param arjunaContext The arjuna context.
*
* None -> None (ignore)
* Active -> Aborting (forget)
* Preparing -> Aborting (forget)
* PreparedSuccess -> PreparedSuccess (invalid state)
* Committing -> Committing (invalid state)
* Aborting -> Aborting (forget)
*/
public synchronized void aborted(final Notification aborted, final MAP map, final ArjunaContext arjunaContext)
{
final State current = state ;
if (current == State.STATE_ACTIVE)
{
changeState(State.STATE_ABORTING) ;
}
else if ((current == State.STATE_PREPARING) || (current == State.STATE_ABORTING))
{
forget() ;
}
}
/**
* Handle the committed event.
* @param committed The committed notification.
* @param map The addressing context.
* @param arjunaContext The arjuna context.
*
* None -> None (ignore)
* Active -> Aborting (invalid state)
* Preparing -> Aborting (invalid state)
* PreparedSuccess -> PreparedSuccess (invalid state)
* Committing -> Committing (forget)
* Aborting -> Aborting (invalid state)
*/
public synchronized void committed(final Notification committed, final MAP map, final ArjunaContext arjunaContext)
{
final State current = state ;
if (current == State.STATE_ACTIVE)
{
changeState(State.STATE_ABORTING) ;
}
else if ((current == State.STATE_PREPARING) || (current == State.STATE_COMMITTING))
{
forget() ;
}
}
/**
* Handle the prepared event.
* @param prepared The prepared notification.
* @param map The addressing context.
* @param arjunaContext The arjuna context.
*
* None -> Durable: (send rollback), Volatile: Invalid state: none
* Active -> Aborting (invalid state)
* Preparing -> PreparedSuccess (Record Vote)
* PreparedSuccess -> PreparedSuccess (ignore)
* Committing -> Committing (resend Commit)
* Aborting -> Aborting (resend Rollback and forget)
*/
public void prepared(final Notification prepared, final MAP map, final ArjunaContext arjunaContext)
{
final State current ;
synchronized(this)
{
current = state ;
if (current == State.STATE_ACTIVE)
{
changeState(State.STATE_ABORTING) ;
}
else if (current == State.STATE_PREPARING)
{
changeState(State.STATE_PREPARED_SUCCESS) ;
}
}
if (current == State.STATE_COMMITTING)
{
sendCommit() ;
}
else if ((current == State.STATE_ABORTING))
{
if (durable) {
sendRollback();
} else {
sendUnknownTransaction(map, arjunaContext) ;
}
forget();
}
else if ((current == null) && !readOnly)
{
if (durable)
{
sendRollback() ;
}
else
{
sendUnknownTransaction(map, arjunaContext) ;
}
}
}
/**
* Handle the readOnly event.
* @param readOnly The readOnly notification.
* @param map The addressing context.
* @param arjunaContext The arjuna context.
*
* None -> None (ignore)
* Active -> Active (forget)
* Preparing -> Preparing (forget)
* PreparedSuccess -> PreparedSuccess (invalid state)
* Committing -> Committing (invalid state)
* Aborting -> Aborting (forget)
*/
public synchronized void readOnly(final Notification readOnly, final MAP map, final ArjunaContext arjunaContext)
{
final State current = state ;
if ((current == State.STATE_ACTIVE) || (current == State.STATE_PREPARING) ||
(current == State.STATE_ABORTING))
{
if (current != State.STATE_ABORTING)
{
this.readOnly = true ;
}
forget() ;
}
}
/**
* Handle the soap fault event.
* @param soapFault The soap fault.
* @param map The addressing context.
* @param arjunaContext The arjuna context.
*
*/
public void soapFault(final SoapFault soapFault, final MAP map, final ArjunaContext arjunaContext)
{
if (WSTLogger.logger.isTraceEnabled())
{
final InstanceIdentifier instanceIdentifier = arjunaContext.getInstanceIdentifier() ;
final SoapFaultType soapFaultType = soapFault.getSoapFaultType() ;
final QName subCode = soapFault.getSubcode() ;
WSTLogger.logger.tracev("Unexpected SOAP fault for coordinator {0}: {1} {2}", new Object[] {instanceIdentifier, soapFaultType, subCode}) ;
}
}
/**
* Handle the prepare event.
*
* None -> None (invalid state)
* Active -> Preparing (send prepare)
* Preparing -> Preparing (resend prepare)
* PreparedSuccess -> PreparedSuccess (do nothing)
* Committing -> Committing (invalid state)
* Aborting -> Aborting (invalid state)
*/
public State prepare()
{
final State current ;
synchronized(this)
{
current = state ;
if (current == State.STATE_ACTIVE)
{
changeState(State.STATE_PREPARING) ;
}
}
if ((current == State.STATE_ACTIVE) || (current == State.STATE_PREPARING))
{
sendPrepare() ;
}
waitForState(State.STATE_PREPARING, TransportTimer.getTransportTimeout()) ;
synchronized(this)
{
if (state != State.STATE_PREPARING)
{
return state ;
}
if (timerTask != null)
{
timerTask.cancel() ;
timerTask = null;
}
// ok, we leave the participant stub active because the coordinator will attempt
// to roll it back when it notices that this has failed
return state ;
}
}
/**
* Handle the commit event.
*
* None -> None (invalid state)
* Active -> Active (invalid state)
* Preparing -> Preparing (invalid state)
* PreparedSuccess -> Committing (send commit)
* Committing -> Committing (resend commit)
* Aborting -> Aborting (invalid state)
*/
public State commit()
{
final State current ;
synchronized(this)
{
current = state ;
if (current == State.STATE_PREPARED_SUCCESS)
{
changeState(State.STATE_COMMITTING) ;
}
}
if ((current == State.STATE_PREPARED_SUCCESS) || (current == State.STATE_COMMITTING))
{
sendCommit() ;
}
waitForState(State.STATE_COMMITTING, TransportTimer.getTransportTimeout()) ;
synchronized(this)
{
if (state != State.STATE_COMMITTING)
{
// if this is a recovered participant then forget will not have
// deactivated the entry so that this (recovery) thread can
// detect it and update its log entry. so we need to deactivate
// the entry here.
if (recovered) {
CoordinatorProcessor.getProcessor().deactivateCoordinator(this) ;
}
return state ;
}
// the participant is still uncommitted so it will be rewritten to the log.
// it remains activated in case a committed message comes in between now and
// the next scan. the recovery code will detect this active participant when
// rescanning the log and use it instead of recreating a new one.
// we need to mark this one as recovered so it does not get deleted until
// the next scan
recovered = true;
return State.STATE_COMMITTING;
}
}
/**
* Handle the rollback event.
*
* None -> None (invalid state)
* Active -> Aborting (send rollback)
* Preparing -> Aborting (send rollback)
* PreparedSuccess -> Aborting (send rollback)
* Committing -> Committing (invalid state)
* Aborting -> Aborting (do nothing)
*/
public State rollback()
{
final State current ;
synchronized(this)
{
current = state ;
if ((current == State.STATE_ACTIVE) || (current == State.STATE_PREPARING) ||
(current == State.STATE_PREPARED_SUCCESS))
{
changeState(State.STATE_ABORTING) ;
}
}
if ((current == State.STATE_ACTIVE) || (current == State.STATE_PREPARING) ||
(current == State.STATE_PREPARED_SUCCESS))
{
sendRollback() ;
}
else if (current == State.STATE_ABORTING)
{
forget() ;
}
waitForState(State.STATE_ABORTING, TransportTimer.getTransportTimeout()) ;
synchronized(this)
{
if (state != State.STATE_ABORTING)
{
// means state must be null and the participant has already been deactivated
return state ;
}
// the participant has not confirmed that it is aborted so it will be written to the
// log in the transaction's heuristic list. it needs to be deactivated here
// so that subsequent ABORTED messages are handled correctly, either by sending
// an UnknownTransaction fault or a rollback depending upon whether it is
// volatile or durable, respectively
forget();
return State.STATE_ABORTING;
}
}
/**
* Handle the comms timeout event.
*
* Preparing -> Preparing (resend Prepare)
* Committing -> Committing (resend Commit)
*/
private void commsTimeout(TimerTask caller)
{
final State current ;
synchronized(this)
{
if (timerTask != caller) {
// the timer was cancelled but it went off before it could be cancelled
return;
}
current = state ;
}
if (current == State.STATE_PREPARING)
{
sendPrepare() ;
}
else if (current == State.STATE_COMMITTING)
{
sendCommit() ;
}
}
/**
* Get the coordinator id.
* @return The coordinator id.
*/
public String getId()
{
return id ;
}
/**
* Get the participant endpoint reference
* @return The participant endpoint reference
*/
public W3CEndpointReference getParticipant()
{
return participant ;
}
/**
* Is the participant durable?
* @return true if durable, false otherwise.
*/
public boolean isDurable()
{
return durable ;
}
/**
* Is the participant recovered?
* @return true if recovered, false otherwise.
*/
public boolean isRecovered()
{
return recovered ;
}
/**
* Was this a read only response?
* @return true if a read only response, false otherwise.
*/
public synchronized boolean isReadOnly()
{
return readOnly ;
}
/**
* Retrieve the current state of this participant
* @return the current state.
*/
public synchronized State getState()
{
return state;
}
/**
* Change the state and notify any listeners.
* @param state The new state.
*/
private synchronized void changeState(final State state)
{
if (this.state != state)
{
this.state = state ;
notifyAll() ;
}
}
/**
* Wait for the state to change from the specified state.
* @param origState The original state.
* @param delay The maximum time to wait for (in milliseconds).
* @return The current state.
*/
private State waitForState(final State origState, final long delay)
{
final long end = System.currentTimeMillis() + delay ;
synchronized(this)
{
while(state == origState)
{
final long remaining = end - System.currentTimeMillis() ;
if (remaining <= 0)
{
break ;
}
try
{
wait(remaining) ;
}
catch (final InterruptedException ie) {} // ignore
}
return state ;
}
}
/**
* Forget the current coordinator.
*/
private void forget()
{
// first, change state to null to indicate that the participant has completed.
changeState(null) ;
// participants which have not been recovered from the log can be deactivated now.
// participants which have been recovered are left for the recovery thread to deactivate.
// this is because the recovery thread may have timed out waiting for a response to
// the commit message and gone on to complete its scan and suspend. the next scan
// will detect this activated participant and note that it has completed. if a crash
// happens in between the recovery thread can safely recreate and reactivate the
// participant and resend the commit since the commit/committed exchange is idempotent.
if (!recovered) {
CoordinatorProcessor.getProcessor().deactivateCoordinator(this) ;
}
}
/**
* Send the prepare message.
*
*/
private void sendPrepare()
{
TimerTask newTimerTask = createTimerTask();
synchronized (this) {
// cancel any existing timer task
if (timerTask != null) {
timerTask.cancel();
}
// install the new timer task. this signals our intention to post a prepare which may need
// rescheduling later but allows us to drop the lock on this while we are in the comms layer.
// our intention can be revised by another thread by reassigning the field to a new task
// or null
timerTask = newTimerTask;
}
// ok now try the prepare
try
{
ParticipantClient.getClient().sendPrepare(participant, createContext(), instanceIdentifier) ;
}
catch (final Throwable th)
{
if (WSTLogger.logger.isTraceEnabled())
{
WSTLogger.logger.tracev("Unexpecting exception while sending Prepare", th) ;
}
}
// reobtain the lock before deciding whether to schedule the timer
synchronized (this) {
if (timerTask != null && timerTask.equals(newTimerTask)) {
// the timer task has not been cancelled so schedule it if appropriate
if (state == State.STATE_PREPARING) {
scheduleTimer(newTimerTask);
} else {
// no need to schedule it so get rid of it
timerTask = null;
}
}
}
}
/**
* Send the commit message.
*
*/
private void sendCommit()
{
TimerTask newTimerTask = createTimerTask();
synchronized (this) {
// cancel any existing timer task
if (timerTask != null) {
timerTask.cancel();
}
// install the new timer task. this signals our intention to post a commit which may need
// rescheduling later but allows us to drop the lock on this while we are in the comms layer.
// our intention can be revised by another thread by reassigning the field to a new task
// or null
timerTask = newTimerTask;
}
// ok now try the commit
try
{
ParticipantClient.getClient().sendCommit(participant, createContext(), instanceIdentifier) ;
}
catch (final Throwable th)
{
if (WSTLogger.logger.isTraceEnabled())
{
WSTLogger.logger.tracev("Unexpecting exception while sending Commit", th) ;
}
}
// reobtain the lock before deciding whether to schedule the timer
synchronized (this) {
if (timerTask != null && timerTask.equals(newTimerTask)) {
// the timer task has not been cancelled so schedule it if appropriate
if (state == State.STATE_COMMITTING) {
scheduleTimer(newTimerTask);
} else {
// no need to schedule it so get rid of it
timerTask = null;
}
}
}
}
/**
* Send the rollback message.
*
*/
private void sendRollback()
{
try
{
ParticipantClient.getClient().sendRollback(participant, createContext(), instanceIdentifier) ;
}
catch (final Throwable th)
{
if (WSTLogger.logger.isTraceEnabled())
{
WSTLogger.logger.tracev("Unexpecting exception while sending Rollback", th) ;
}
}
}
/**
* Send the UnknownTransaction message.
*
*/
private void sendUnknownTransaction(final MAP map, final ArjunaContext arjunaContext)
{
try
{
final MAP faultMAP = AddressingHelper.createFaultContext(map, MessageId.getMessageId()) ;
final InstanceIdentifier instanceIdentifier = arjunaContext.getInstanceIdentifier() ;
final String message = WSTLogger.i18NLogger.get_wst11_messaging_engines_CoordinatorEngine_sendUnknownTransaction_1();
final SoapFault soapFault = new SoapFault11(SoapFaultType.FAULT_SENDER, AtomicTransactionConstants.WSAT_ERROR_CODE_UNKNOWN_TRANSACTION_QNAME, message) ;
ParticipantClient.getClient().sendSoapFault(faultMAP, soapFault, instanceIdentifier) ;
}
catch (final Throwable th)
{
WSTLogger.i18NLogger.warn_wst11_messaging_engines_CoordinatorEngine_sendUnknownTransaction_2(id, th);
}
}
/**
* create a timer task to handle a comms timeout
*
* @return the timer task
*/
private TimerTask createTimerTask()
{
return new TimerTask() {
public void run() {
commsTimeout(this) ;
}
} ;
}
/**
* schedule a timer task to handle a commms timeout
* @param timerTask the timer task to be scheduled
*/
private void scheduleTimer(TimerTask timerTask)
{
TransportTimer.getTimer().schedule(timerTask, TransportTimer.getTransportPeriod()) ;
}
/**
* Create a context for the outgoing message.
* @return The addressing context.
*/
private MAP createContext()
{
final String messageId = MessageId.getMessageId() ;
return AddressingHelper.createNotificationContext(messageId) ;
}
}