/*
 * Copyright (c) 2000, 2017 Oracle and/or its affiliates. All rights reserved.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v. 2.0, which is available at
 * http://www.eclipse.org/legal/epl-2.0.
 *
 * This Source Code may also be made available under the following Secondary
 * Licenses when the conditions for such availability set forth in the
 * Eclipse Public License v. 2.0 are satisfied: GNU General Public License,
 * version 2 with the GNU Classpath Exception, which is available at
 * https://www.gnu.org/software/classpath/license.html.
 *
 * SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
 */

/*
 *  %W% %G%
 */

package com.sun.messaging.jmq.jmsclient;

import java.io.*;
import javax.jms.*;

import java.util.*;
import java.io.IOException;
import java.io.PrintStream;
import com.sun.messaging.jmq.io.*;
import com.sun.messaging.jmq.util.JMQXid;
import com.sun.messaging.jmq.util.timer.WakeupableTimer;
import com.sun.messaging.jmq.util.timer.TimerEventHandler;
import com.sun.messaging.AdministeredObject;
import com.sun.messaging.jms.ra.api.JMSRAManagedConnection;
import com.sun.messaging.jms.ra.api.JMSRAXASession;
import com.sun.messaging.jmq.jmsclient.resources.ClientResources;
import java.util.logging.Logger;
import java.util.logging.Level;

/**
 * <P>
 * A JMS Session is a single threaded context for producing and consuming messages. Although it may allocate provider
 * resources outside the Java virtual machine, it is considered a light-weight JMS object.
 *
 * <P>
 * A session serves several purposes:
 *
 * <UL>
 * <LI>It is a factory for its message producers and consumers.
 * <LI>It supplies provider-optimized message factories.
 * <LI>It supports a single series of transactions that combine work spanning its producers and consumers into atomic
 * units.
 * <LI>A session defines a serial order for the messages it consumes and the messages it produces.
 * <LI>A session retains messages it consumes until they have been acknowledged.
 * <LI>A session serializes execution of message listeners registered with it's message consumers.
 * </UL>
 *
 * <P>
 * A session can create and service multiple message producers and consumers.
 *
 * <P>
 * One typical use is to have a thread block on a synchronous MessageConsumer until a message arrives. The thread may
 * then use one or more of the Session's MessageProducers.
 *
 * <P>
 * If a client desires to have one thread producing messages while others consume them, the client should use a separate
 * Session for its producing thread.
 *
 * <P>
 * Once a connection has been started, any session with a registered message listener(s) is dedicated to the thread of
 * control that delivers messages to it. It is erroneous for client code to use this session or any of its constituent
 * objects from another thread of control. The only exception to this is the use of the session or connection close
 * method.
 *
 * <P>
 * It should be easy for most clients to partition their work naturally into Sessions. This model allows clients to
 * start simply and incrementally add message processing complexity as their need for concurrency grows.
 *
 * <P>
 * The close method is the only session method that can be called while some other session method is being executed in
 * another thread.
 *
 * <P>
 * A session may be optionally specified as transacted. Each transacted session supports a single series of
 * transactions. Each transaction groups a set of message sends and a set of message receives into an atomic unit of
 * work. In effect, transactions organize a session's input message stream and output message stream into series of
 * atomic units. When a transaction commits, its atomic unit of input is acknowledged and its associated atomic unit of
 * output is sent. If a transaction rollback is done, its sent messages are destroyed and the session's input is
 * automatically recovered.
 *
 * <P>
 * The content of a transaction's input and output units is simply those messages that have been produced and consumed
 * within the session's current transaction.
 *
 * <P>
 * A transaction is completed using either its session's <CODE>commit</CODE> or <CODE>rollback</CODE> method. The
 * completion of a session's current transaction automatically begins the next. The result is that a transacted session
 * always has a current transaction within which its work is done.
 *
 * <P>
 * JTS, or some other transaction monitor may be used to combine a session's transaction with transactions on other
 * resources (databases, other JMS sessions, etc.). Since Java distributed transactions are controlled via JTA, use of
 * the session's commit and rollback methods in this context is prohibited.
 *
 * <P>
 * JMS does not require support for JTA; however, it does define how a provider supplies this support.
 *
 * <P>
 * Although it is also possible for a JMS client to handle distributed transactions directly, it is unlikely that many
 * JMS clients will do this. Support for JTA in JMS is targeted at systems vendors who will be integrating JMS into
 * their application server products.
 *
 * @see javax.jms.QueueSession
 * @see javax.jms.TopicSession
 * @see javax.jms.XASession
 */

public class SessionImpl implements JMSRAXASession, Traceable, ContextableSession {

    /**
     * With this acknowledgement mode, the session automatically acknowledges a client's receipt of a message when it has
     * either successfully returned from a call to receive or the message listener it has called to process the message
     * successfully returns.
     */

    // static final int AUTO_ACKNOWLEDGE = 1;

    /**
     * With this acknowledgement mode, the client acknowledges a message by calling a message's acknowledge method.
     * Acknowledging a message acknowledges all messages that the Session has consumed.
     *
     * <P>
     * When client acknowledgment mode is used, a client may build up a large number of unacknowledged messages while
     * attempting to process them. A JMS provider should provide administrators with a way to limit client over-run so that
     * clients are not driven to resource exhaustion and ensuing failure when some resource they are using is temporarily
     * blocked.
     */

    // static final int CLIENT_ACKNOWLEDGE = 2;

    /**
     * This acknowledgement mode instructs the session to lazily acknowledge the delivery of messages. This is likely to
     * result in the delivery of some duplicate messages if JMS fails, it should only be used by consumers that are tolerant
     * of duplicate messages. Its benefit is the reduction of session overhead achieved by minimizing the work the session
     * does to prevent duplicates.
     */

    // static final int DUPS_OK_ACKNOWLEDGE = 3;

    private ServerSessionRunner serverSessionRunner = null;
    private ConnectionConsumerImpl connectionConsumer = null;

    // default values.
    protected ConnectionImpl connection = null;
    protected boolean isTransacted = false;
    protected int acknowledgeMode = Session.AUTO_ACKNOWLEDGE;
    protected SessionReader sessionReader = null;
    // protected SessionTransaction transaction = null;

    protected SessionQueue sessionQueue = null;

    protected ReadChannel readChannel = null;
    // protected FlowControl flowControl = null;

    protected Hashtable consumers = new Hashtable();
    // producers are added here in case we need to recover
    // the connection
    protected Vector producers = new Vector();

    protected WriteChannel writeChannel = null;
    protected Long sessionId = null;
    protected ProtocolHandler protocolHandler = null;
    protected Transaction transaction = null;

    protected boolean failoverOccurred = false;

    protected int dupsOkLimit = 10; // dups ok non ack limit.

    // flag to indicate if we need to check unacked message count
    protected boolean isAckLimited = false;

    // only used if isAckLimited set to true
    protected int ackLimit = 100; // client non acknowledge limit
    // number of messages not yet acked so far.
    protected int ackCounter = 0;

    // queue for unacked messages,
    protected Vector unAckedMessageQueue = new Vector();

    protected boolean isClosed = false;
    protected boolean isStopped = false;

    // is the XASession closed
    // protected boolean isXAClosed = false;
    // is the XASession in rollback/commit
    // protected boolean isXAInRC = false;

    // for flow control
    protected boolean protectMode = false;

    // XXX chiaming REVISIT: init when it is needed.
    protected Hashtable browserConsumers = new Hashtable();

    // for acknowledgement.
    ReadWritePacket ackPkt = new ReadWritePacket();
    ByteArrayOutputStream bos = new ByteArrayOutputStream(ProtocolHandler.ACK_MESSAGE_BODY_SIZE);
    DataOutputStream dos = new DataOutputStream(bos);

    ReadWritePacket expirePkt = new ReadWritePacket();
    ByteArrayOutputStream expireBos = new ByteArrayOutputStream(ProtocolHandler.ACK_MESSAGE_BODY_SIZE);
    DataOutputStream expireDos = new DataOutputStream(expireBos);

    protected boolean setJMSXConsumerTXID = false;

    protected boolean debug = Debug.debug;

    // session sync object - used for session sync operations.
    // Such as close, commit, recover, rollback, etc.
    private Object syncObject = new Object();
    private boolean inSyncState = false;

    // reason why inSyncState is true
    // we are only interested in knowing whether the other thread is executing close() or something else
    private int inSyncStateOperation = INSYNCSTATE_NOTSET;
    private static final int INSYNCSTATE_NOTSET = 0;
    private static final int INSYNCSTATE_SESSION_CLOSING = 1;
    private static final int INSYNCSTATE_CONSUMER_CLOSING = 2;
    private static final int INSYNCSTATE_OTHER = 3;

    // session sync object to replace synchronized (this).
    // application can sync the session object and interfere the client runtime.
    // bug 6302418 - imqReconnectEnabled does not work well on cluster.
    private Object sessionSyncObj = new Object();

    protected boolean xaTxnMode = false;

    // sync object used for endpoint consumers in the RA
    private Object raEndpointSyncObj = new Object();

    // this field is never used.
    // private boolean raEndpointSession = false;

    // RA mc object to acquire txn cntxt
    private JMSRAManagedConnection mc = null;

    private boolean isDedicatedToServerSession = false;

    // XXX PROTOCOL 3.5
    // SessionID assigned to this session by the broker.
    private long brokerSessionID = -1;

    private int TEST_ackCount = 0;
    private int TEST_rxCount = 0;

    // if set, dups ok acks when reached unacked limit or session Q is empty.
    protected boolean dupsOkAckOnEmptyQueue = false;
    // if set, dups ok acks only when reached unack limit.
    protected boolean dupsOkAckOnLimit = false;
    // if set, dups ok acks when reached unack limit or max timeout.
    protected boolean dupsOkAckOnTimeout = false;
    // dups ok timeout value -- to set to session reader.
    protected long dupsOkAckTimeout = 0;
    // dups ok timestamp
    protected long dupsOkTimestamp = 0;

    // created to prevent deadlock - bugid 4987018
    protected Object dupsOkSyncObj = new Object();

    // allow session extension flag. if set to true, MQ extensions are allowed.
    // such as NO_ACK mode.
    protected boolean allowExtensions = false;

    // private volatile boolean inResetState = false;

    // connection logging domain name.
    public static final String SESSION_LOGGER_NAME = ConnectionImpl.ROOT_LOGGER_NAME + ".session";

    protected static final Logger sessionLogger = Logger.getLogger(SESSION_LOGGER_NAME, ClientResources.CLIENT_RESOURCE_BUNDLE_NAME);

    // flag to indicate that the remote broker where the consumer(s) consumes messages from
    // had failed. Messages are not able to commit/acknowledge until rollback/recover.
    // see recreateConsumers() for detail information.
    protected volatile boolean remore_broker_failed = false;

    // HACC -- rollback only for the current transaction
    // this is set when ServerSessionRunner.run() received
    // exception from listener or ack failed (bug 6667940).
    protected volatile boolean isRollbackOnly = false;
    // assigned when isRollbackOnly happened.
    protected Throwable rollbackCause = null;

    // should only be used for JMS local transaction in non-HA mode
    public static final boolean autoStartTxn = Boolean.getBoolean("imq.autoStartTxn");

    public static final boolean noBlockUntilTxnCompletes = Boolean.getBoolean("imq.noBlockUntilTxnCompletes");
    public static final boolean noBlockOnAutoAckNPTopics = Boolean.getBoolean("imq.noBlockOnAutoAckNPTopics");
    private static long waitTimeoutForConsumerCloseDone = Integer.getInteger("imqWaitTimeoutForConsumerCloseDone", 90000).intValue();

    private ThreadLocal<Boolean> isMessageListener = new ThreadLocal<Boolean>();

    private Object asyncSendLock = new Object();
    private ArrayList<AsyncSendCallback> asyncSends = new ArrayList<AsyncSendCallback>();
    private boolean noAsyncSendCBProcessor = true;
    protected WakeupableTimer asyncSendCBProcessor = null;

    protected static final Exception asyncSendWaitTimeoutEx = getAsyncSendWaitTimeoutException();

    protected static final Exception noAsyncSendCBProcessorEx = getNoAsyncSendCBProcessorException();

    protected static final Exception connectionBrokenEx = getConnectionBrokenException();

    private static Exception getAsyncSendWaitTimeoutException() {
        String emsg = AdministeredObject.cr.getKString(ClientResources.X_ASYNC_SEND_COMPLETION_WAIT_TIMEOUT);
        return new JMSException(emsg, ClientResources.X_ASYNC_SEND_COMPLETION_WAIT_TIMEOUT);
    }

    private static Exception getNoAsyncSendCBProcessorException() {
        String emsg = AdministeredObject.cr.getKString(ClientResources.X_NO_ASYNC_SEND_LISTENER_PROCESSOR_THREAD);
        return new javax.jms.IllegalStateException(emsg, ClientResources.X_NO_ASYNC_SEND_LISTENER_PROCESSOR_THREAD);
    }

    private static Exception getConnectionBrokenException() {
        String emsg = AdministeredObject.cr.getKString(ClientResources.E_CONNECTION_BROKEN);
        return new JMSException(emsg, ClientResources.E_CONNECTION_BROKEN);
    }

    protected SessionImpl() {
    }

    public SessionImpl(ConnectionImpl connection) throws JMSException {
        this(connection, false, Session.AUTO_ACKNOWLEDGE, false, null);
    }

    /**
     * Constructor for standard JMS sessions.
     *
     * @param connection
     * @param isTransacted
     * @param acknowledgeMode
     * @throws JMSException
     */
    public SessionImpl(ConnectionImpl connection, boolean isTransacted, int acknowledgeMode) throws JMSException {
        this(connection, isTransacted, acknowledgeMode, false, null);
    }

    public SessionImpl(ConnectionImpl connection, boolean isTransacted, int acknowledgeMode, JMSRAManagedConnection mc) throws JMSException {
        this(connection, isTransacted, acknowledgeMode, false, mc);
    }

    /**
     * Constructor for MQ extended sessions. Use this constructor for non transacted MQ extended session -- such as
     * NO_ACKNOWLEDGE mode.
     *
     * @param connection
     * @param acknowledgeMode
     * @throws JMSException
     */
    public SessionImpl(ConnectionImpl connection, int acknowledgeMode) throws JMSException {
        this(connection, false, acknowledgeMode, true, null);
    }

    public SessionImpl(ConnectionImpl connection, boolean isTransacted, int acknowledgeMode, boolean allowJMSExtension, JMSRAManagedConnection mc)
            throws JMSException {

        try {

            // session's queue data structure. -- 6089070
            sessionQueue = new SessionQueue();
            sessionQueue.validateQueue();

            // set allow extension flag.
            this.allowExtensions = allowJMSExtension;

            this.connection = connection;

            /**
             * check acknowledge mode
             */
            if (isTransacted == false) {
                if (acknowledgeMode == 0) {
                    acknowledgeMode = Session.AUTO_ACKNOWLEDGE;
                }

                checkAckMode(acknowledgeMode);
            }

            this.writeChannel = connection.getWriteChannel();
            this.readChannel = connection.getReadChannel();
            this.protocolHandler = connection.getProtocolHandler();

            this.isTransacted = isTransacted;

            this.acknowledgeMode = acknowledgeMode;

            sessionId = connection.getNextSessionId();

            if (mc != null) {
                this.mc = mc;
            }

            init();

            logLifeCycle(ClientResources.I_SESSION_CREATED);

        } catch (JMSException jmse) {
            ExceptionHandler.throwJMSException(jmse);
        }
    }

    /**
     * Check ack mode.
     */
    private void checkAckMode(int ackMode) throws JMSException {

        if (ackMode != Session.AUTO_ACKNOWLEDGE && ackMode != Session.CLIENT_ACKNOWLEDGE && ackMode != Session.DUPS_OK_ACKNOWLEDGE) {

            if (this.allowExtensions == true) {
                // if this is MQ extension, NO_ACK mode is allowed.
                if (ackMode == com.sun.messaging.jms.Session.NO_ACKNOWLEDGE) {

                    if (connection.getBrokerProtocolLevel() <= PacketType.VERSION350) {
                        String errorString = AdministeredObject.cr.getKString(ClientResources.X_BROKER_NOT_SUPPORT_NO_ACK_MODE, connection.getBrokerVersion());

                        JMSException jmse = new com.sun.messaging.jms.JMSException(errorString, ClientResources.X_BROKER_NOT_SUPPORT_NO_ACK_MODE);

                        ExceptionHandler.throwJMSException(jmse);
                    }

                    return;
                }
            }

            String ackModeStr = String.valueOf(ackMode);
            String errorString = AdministeredObject.cr.getKString(ClientResources.X_INVALID_ACKNOWLEDGE_MODE, ackModeStr);

            JMSException jmse = new JMSException(errorString, ClientResources.X_INVALID_ACKNOWLEDGE_MODE);

            ExceptionHandler.throwJMSException(jmse);
        }

    }

    private void init() throws JMSException {

        serverSessionRunner = new ServerSessionRunner(this, null);

        // XXX PROTOCOL3.5
        if (connection.getBrokerProtocolLevel() >= PacketType.VERSION350) {
            protocolHandler.createSession(this);
        }

        // construct a transaction object to handle transactions
        // handle differently if under an mc
        if (isTransacted) {
            if (mc == null) {
                // setup Transaction delegate for local txns
                transaction = new Transaction(this, true);
            } else {
                transaction = new Transaction(this, false);
                if (mc.xaTransactionStarted()) {
                    transaction.setTransactionID(mc.getTransactionID());
                    xaTxnMode = true;
                } // else {
                  // transaction.startNewLocalTransaction();
                  // }
            }
        }

        /**
         * move the following statement to the begining of the constructor. there seems to have a jdk bug that caused the usage
         * of this object's internal data structure. (6174742, 6089070)
         */
        // sessionQueue = new SessionQueue();

        // if connection is in stop mode, lock the queue
        if (connection.getIsStopped()) {
            sessionQueue.setIsLocked(true);
        }

        // construct unAckedPacketQueue if the session is CLIENT_ACKNOWLEDGE
        // mode or DUPS_OK_ACKNOWLEDGE mode or transacted session.
        // XXX:GT TBF
        /*
         * if ( acknowledgeMode == Session.CLIENT_ACKNOWLEDGE || acknowledgeMode == Session.DUPS_OK_ACKNOWLEDGE || (isTransacted
         * ) ) { unAckedMessageQueue = new Vector(); }
         */

        // put to the readQTable
        connection.addToReadQTable(sessionId, sessionQueue);

        // put to session table
        connection.addSession(this);

        // set dups ok limit
        this.dupsOkLimit = connection.getDupsOkLimit();

        this.isAckLimited = connection.getIsAckLimited();

        // set client ack limit
        this.ackLimit = connection.getAckLimit();

        // set setJMSXConsumerTXID flag
        setJMSXConsumerTXID = connection.connectionMetaData.setJMSXConsumerTXID && isTransacted;

        // protect mode
        protectMode = connection.getProtectMode();

        // ConnectionConsumer workaround 4715054
        isDedicatedToServerSession = connection.getIsDedicatedToConnectionConsumer();

        // dups ok init.
        dupsOkInit();

        // session reader blocks on the session queue and dispatch pkt to the
        // receivers.
        sessionReader = new SessionReader(this);

        if (isDedicatedToServerSession) {
            sessionReader.close();
        } else {
            // start the thread. It is blocked on session queue if queue is locked.
            sessionReader.start();
        }
    }

    /**
     * dups ok ack init. default for appp client: dupsOkAckOnTimeout is set to true. dupsOkAckTimeout is set to 7000 milli
     * secs. for MDB: dupsOkAckOnEmptyQueue is always set to true.
     */
    protected void dupsOkInit() {

        // set only if not transacted mode && not MDB
        if ((isTransacted == false) && (acknowledgeMode == Session.DUPS_OK_ACKNOWLEDGE)) {

            if (isDedicatedToServerSession) {
                dupsOkAckOnEmptyQueue = true;
            } else {

                // get dups ok ack flag.
                dupsOkAckOnEmptyQueue = connection.dupsOkAckOnEmptyQueue;

                if (dupsOkAckOnEmptyQueue == false) {
                    // get timeout value -- default is set to 7000 milli secs
                    dupsOkAckTimeout = connection.dupsOkAckTimeout;

                    if (dupsOkAckTimeout > 0) {
                        dupsOkAckOnTimeout = true;
                    } else {
                        dupsOkAckOnLimit = true;
                        dupsOkAckTimeout = 0;
                    }
                }
            }

        }

        if (debug) {
            if (dupsOkAckOnTimeout || dupsOkAckOnEmptyQueue || dupsOkAckOnLimit) {
                Debug.println("*** dupsOkAckOnEmptyQueue: " + dupsOkAckOnEmptyQueue);
                Debug.println("*** dupsOkAckOnTimeout: " + dupsOkAckOnTimeout);
                Debug.println("*** dupsOkAckTimeout: " + dupsOkAckTimeout);
                Debug.println("*** dupsOkAckOnLimit: " + dupsOkAckOnLimit);
            } else {
                Debug.println("*** Session ackMode:  " + acknowledgeMode);
            }
        }
    }

    protected void switchOnXATransaction() throws JMSException {
        // Switching from a local transaction to an XA transaction
        // will force an implicit rollback -- i.e. have to commit before switching
        // else work done so far is discarded
        // unless an xaTxn has already been started on this session (and possibly suspended)
        if (xaTxnMode) {
            return;
        }
        if (isTransacted) {
            setInSyncState();
            try {
                receiveRollback();
                transaction.rollbackToXA();
            } finally {
                // This will release sync state.
                releaseInSyncState();
            }
        }
        if (transaction == null) {
            // setup Transaction delegate for txns (local = false)
            transaction = new Transaction(this, false);
            // Indicate that Session is transacted
            isTransacted = true;
            setJMSXConsumerTXID = connection.connectionMetaData.setJMSXConsumerTXID;
        }
        // Indicate that we are now in a dist txn
        xaTxnMode = true;
    }

    // Called from XAResource -- prepare() and commit() only
    protected void switchOffXATransaction() {
        // No longer needs to be in a dist txn
        xaTxnMode = false;
        // Done with Transaction delegate!
        isTransacted = false;
        transaction = null;
        // XXX:GT TBF if we need to be able to switch back to a transacted session
    }

    protected /* synchronized */ void addMessageConsumer(MessageConsumerImpl consumer) throws JMSException {
        // XXX PROTOCOL2.1
        /*
         * if (serverSessionRunner.getMessageListener() != null) { String errorString =
         * AdministeredObject.cr.getKString(AdministeredObject.cr.X_SVRSESSION_MESSAGECONSUMER); throw new
         * javax.jms.IllegalStateException(errorString, AdministeredObject.cr.X_SVRSESSION_MESSAGECONSUMER); }
         */

        consumers.put(consumer.interestId, consumer);
    }

    // ConnectionConsumer workaround 4715054
    protected void checkBrowserCreation() throws JMSException {
        if (isDedicatedToServerSession) {
            checkConsumerCreation();
        }
    }

    protected void checkConsumerCreation() throws JMSException {
        if (isDedicatedToServerSession || serverSessionRunner.getMessageListener() != null) {

            String errorString = AdministeredObject.cr.getKString(ClientResources.X_SVRSESSION_MESSAGECONSUMER);

            JMSException jmse = new javax.jms.IllegalStateException(errorString, ClientResources.X_SVRSESSION_MESSAGECONSUMER);

            ExceptionHandler.throwJMSException(jmse);
        }
    }

    protected /* synchronized */ void removeMessageConsumer(MessageConsumerImpl consumer) {
        consumers.remove(consumer.interestId);
    }

    protected MessageConsumerImpl getMessageConsumer(Object key) {
        return (MessageConsumerImpl) consumers.get(key);
    }

    protected /* synchronized */ void addBrowserConsumer(BrowserConsumer consumer) {
        consumer.getBrowser().addBrowserConsumer(consumer);
        browserConsumers.put(consumer.interestId, consumer);
    }

    protected /* synchronized */ void removeBrowserConsumer(BrowserConsumer consumer) {
        browserConsumers.remove(consumer.interestId);
        consumer.getBrowser().removeBrowserConsumer(consumer);
    }

    protected BrowserConsumer getBrowserConsumer(Object key) {
        return (BrowserConsumer) browserConsumers.get(key);
    }

    /**
     * Add the producer in the vector when it is created.
     */
    protected void addMessageProducer(MessageProducerImpl producer) {
        producers.add(producer);
    }

    /**
     * Remove the producer from the table when it is closed.
     */
    protected void removeMessageProducer(MessageProducerImpl producer) {
        producers.remove(producer);
    }

    /**
     * check destination existance in broker
     *
     * @param destination the destination to check
     * @param selector the message selector
     * @param browser if called for QueueBrowser create
     *
     * @exception InvalidDestinationException
     * @exception InvalidSelectorException
     * @exception JMSSecurityException
     * @exception JMSException if fails
     */
    protected void verifyDestination(Destination destination, String selector, boolean browser) throws JMSException {
        protocolHandler.verifyDestination(destination, selector, browser);
    }

    /**
     * get the content (list of SysMessageIDs) in the destination
     *
     * @param destination the destination
     * @param selector the message selector
     *
     * @exception InvalidDestinationException
     * @exception InvalidSelectorException
     * @exception JMSSecurityException
     * @exception JMSException
     */
    /*
     * protected SysMessageID[] getMessageIdSet(Destination destination, String selector) throws JMSException { return
     * protocolHandler.browse(destination, selector); }
     */
    // XXX PROTOCOL2.1
    protected SysMessageID[] getMessageIdSet(Consumer consumer) throws JMSException {
        return protocolHandler.browse(consumer);
    }

    /**
     * request deliver all messages listed (SysMessageIDs) in the ByteArrayOutputStream to the browser consumer
     *
     * @param bos the ByteArrayOutputStream constains list of SysMessaegIDs
     * @param consumer the BrowserConsumer who interest the messages
     *
     * @exception JMSException
     */
    protected boolean requestMessages(ByteArrayOutputStream bos, BrowserConsumer consumer) throws JMSException {
        return protocolHandler.deliver(bos, consumer);
    }

    protected ProtocolHandler getProtocolHandler() {
        return connection.getProtocolHandler();
    }

    protected Long getSessionId() {
        return sessionId;
    }

    protected ConnectionImpl getConnection() {
        return connection;
    }

    protected void addAsyncSendCallback(AsyncSendCallback cb) throws JMSException {
        if (isClosed) {
            String emsg = AdministeredObject.cr.getKString(ClientResources.X_SESSION_CLOSED);
            JMSException jmse = new javax.jms.IllegalStateException(emsg, ClientResources.X_SESSION_CLOSED);
            ExceptionHandler.throwJMSException(jmse);
        }

        createAsyncSendCBProcessor();

        if (noAsyncSendCBProcessor) {
            String emsg = AdministeredObject.cr.getKString(ClientResources.X_NO_ASYNC_SEND_LISTENER_PROCESSOR_THREAD);
            JMSException jmse = new javax.jms.IllegalStateException(emsg, ClientResources.X_NO_ASYNC_SEND_LISTENER_PROCESSOR_THREAD);
            ExceptionHandler.throwJMSException(jmse);
        }
        synchronized (asyncSendLock) {
            asyncSends.add(cb);
        }
    }

    private void createAsyncSendCBProcessor() {
        synchronized (asyncSendLock) {
            if (asyncSendCBProcessor == null) {
                asyncSendCBProcessor = new WakeupableTimer("AsyncSendListenerProcessor[" + toString() + "]", new AsyncSendTimerEventHandler(), 0L, 0L,
                        AdministeredObject.cr.getKString(ClientResources.I_ASYNC_SEND_LISTENER_PROCESSOR_THREAD_START) + "[" + this.toString() + "]",
                        AdministeredObject.cr.getKString(ClientResources.I_ASYNC_SEND_LISTENER_PROCESSOR_THREAD_EXIT) + "[" + this.toString() + "]");
                noAsyncSendCBProcessor = false;
            }
        }
    }

    private class AsyncSendTimerEventHandler implements TimerEventHandler {
        public AsyncSendTimerEventHandler() {
        }

        @Override
        public void handleOOMError(Throwable e) {
            sessionLogger.log(Level.WARNING, "OutOfMemoryError occurred in AsyncSendListenerProcessor thread[" + SessionImpl.this.toString() + "]", e);
        }

        @Override
        public void handleLogInfo(String msg) {
            sessionLogger.log(Level.FINE, msg + "[" + SessionImpl.this.toString() + "]");
        }

        @Override
        public void handleLogWarn(String msg, Throwable e) {
            sessionLogger.log(Level.WARNING, msg + "[" + SessionImpl.this.toString() + "]", e);
        }

        @Override
        public void handleLogError(String msg, Throwable e) {
            sessionLogger.log(Level.WARNING, msg + "[" + SessionImpl.this.toString() + "]", e);
        }

        @Override
        public void handleTimerExit(Throwable e) {
            if (isClosed) {
                return;
            }
            synchronized (asyncSendLock) {
                noAsyncSendCBProcessor = true;
            }
            String emsg = AdministeredObject.cr.getKString(ClientResources.E_ASYNC_SEND_CALLBACK_THREAD_EXIT);
            sessionLogger.log(Level.SEVERE, emsg + "[" + SessionImpl.this.toString() + "]", e);
        }

        @Override
        public long runTask() {
            sessionLogger.log(Level.FINEST, "asyncSendCBProcessor start runTask[" + SessionImpl.this.toString() + "]");
            long ret = 0L; // wait for next wakeup

            AsyncSendCallback cb = null;
            ArrayList<AsyncSendCallback> calls = new ArrayList<AsyncSendCallback>();
            synchronized (asyncSendLock) {
                if (asyncSends.size() == 0) {
                    sessionLogger.log(Level.FINEST, "asyncSendCBProcessor end runTask[" + SessionImpl.this.toString() + "] ret=0L");
                    return 0L;
                }
                Iterator<AsyncSendCallback> itr = asyncSends.iterator();
                while (itr.hasNext()) {
                    cb = itr.next();
                    if (!cb.hasSendReturned()) {
                        break;
                    }
                    if (cb.isCompleted() || cb.isExceptioned()) {
                        calls.add(cb);
                    } else {
                        if (!cb.isOnAckWait()) {
                            break;
                        }
                        ret = connection.getAsyncSendCompletionWaitTimeout();
                        if (!cb.isTimedout()) {
                            cb.startTimeoutTimer();
                            break;
                        } else {
                            calls.add(cb);
                        }
                    }
                }
            }
            Iterator<AsyncSendCallback> itr = calls.iterator();
            while (itr.hasNext()) {
                cb = itr.next();
                cb.callCompletionListener();
            }
            calls.clear();
            sessionLogger.log(Level.FINEST, "asyncSendCBProcessor end runTask[" + SessionImpl.this.toString() + "] ret=" + ret);
            return ret;
        }
    }

    protected void removeAsyncSendCallback(AsyncSendCallback cb) {
        synchronized (asyncSendLock) {
            asyncSends.remove(cb);
            asyncSendLock.notifyAll();
        }
    }

    protected void writeJMSMessage(Message message, AsyncSendCallback asynccb) throws JMSException {
        // not calling checkSessionState just for performance reason ...
        if (isClosed) {
            String errorString = AdministeredObject.cr.getKString(ClientResources.X_SESSION_CLOSED);
            JMSException jmse = new javax.jms.IllegalStateException(errorString, ClientResources.X_SESSION_CLOSED);

            ExceptionHandler.throwJMSException(jmse);
        }
        if (asynccb != null && xaTxnMode) {
            String errorString = AdministeredObject.cr.getKString(ClientResources.X_ASYNC_SEND_XA_TXN);
            JMSException jmse = new JMSException(errorString, ClientResources.X_ASYNC_SEND_XA_TXN);

            ExceptionHandler.throwJMSException(jmse);
        }
        if (isTransacted) {
            checkFailOver();
            transaction.send(message, asynccb);
        } else {
            writeChannel.writeJMSMessage(message, asynccb);
        }
    }

    protected void waitAllAsyncSendCompletion(MessageProducerImpl producer) throws JMSException {
        checkPermissionForAsyncSend();
        if (connection.isBroken()) {
            synchronized (asyncSendLock) {
                asyncSendLock.notifyAll();
            }
        }

        AsyncSendCallback cb = null;
        long endtime = System.currentTimeMillis() + connection.getAsyncSendCompletionWaitTimeout();
        long remaining = 0L;
        if (producer == null) {
            int asize = 0;
            synchronized (asyncSendLock) {
                asize = asyncSends.size();
            }
            boolean firstround = true;
            while (asize > 0) {
                remaining = connection.getAsyncSendCompletionWaitTimeout();
                synchronized (asyncSendLock) {
                    boolean logged = false;
                    while (asyncSends.size() > 0 && remaining > 0L && (!firstround || !connection.isBroken() || !noAsyncSendCBProcessor)) {
                        try {
                            if (!logged) {
                                String msg = AdministeredObject.cr.getKString(ClientResources.I_WAIT_ASYNC_SENDS_COMPLETE_SESSION, String.valueOf(remaining),
                                        this);
                                sessionLogger.log(Level.INFO, msg);
                                logged = true;
                            }
                            asyncSendLock.wait(remaining);
                        } catch (InterruptedException e) {
                        }
                        remaining = endtime - System.currentTimeMillis();
                    }
                    if (connection.isBroken()) {
                        asyncSendLock.notifyAll();
                    }
                    if (asyncSends.size() > 0) {
                        Exception ex = (noAsyncSendCBProcessor ? noAsyncSendCBProcessorEx : asyncSendWaitTimeoutEx);
                        if (connection.isBroken()) {
                            ex = connectionBrokenEx;
                        }
                        ex.fillInStackTrace();
                        Iterator<AsyncSendCallback> itr = asyncSends.iterator();
                        while (itr.hasNext()) {
                            cb = itr.next();
                            cb.processException(ex);

                        }
                        if (noAsyncSendCBProcessor) {
                            String emsg = AdministeredObject.cr.getKString(ClientResources.X_NO_ASYNC_SEND_LISTENER_PROCESSOR_THREAD);
                            JMSException jmse = new JMSException(emsg, ClientResources.X_NO_ASYNC_SEND_LISTENER_PROCESSOR_THREAD);
                            ExceptionHandler.throwJMSException(jmse);
                        }
                    }
                    firstround = false;
                    asize = asyncSends.size();
                } // synchronized
            }
        } else {
            boolean loggered = false;
            boolean found = true;
            boolean firstround = true;
            remaining = connection.getAsyncSendCompletionWaitTimeout();
            while (found) {
                found = false;
                synchronized (asyncSendLock) {
                    Iterator<AsyncSendCallback> itr = asyncSends.iterator();
                    while (itr.hasNext()) {
                        cb = itr.next();
                        if (cb.producer == producer) {
                            found = true;
                            if (remaining == 0L || (firstround && (connection.isBroken() || noAsyncSendCBProcessor))) {
                                Exception ex = (noAsyncSendCBProcessor ? noAsyncSendCBProcessorEx : asyncSendWaitTimeoutEx);
                                if (connection.isBroken()) {
                                    ex = connectionBrokenEx;
                                    asyncSendLock.notifyAll();
                                }
                                ex.fillInStackTrace();
                                cb.processException(ex);
                                if (remaining == 0L) {
                                    remaining = connection.getAsyncSendCompletionWaitTimeout();
                                    loggered = false;
                                    break;
                                }
                            } else {
                                if (noAsyncSendCBProcessor) {
                                    String emsg = AdministeredObject.cr.getKString(ClientResources.X_NO_ASYNC_SEND_LISTENER_PROCESSOR_THREAD);
                                    JMSException jmse = new JMSException(emsg, ClientResources.X_NO_ASYNC_SEND_LISTENER_PROCESSOR_THREAD);
                                    ExceptionHandler.throwJMSException(jmse);
                                }

                                try {
                                    if (!loggered) {
                                        String msg = AdministeredObject.cr.getKString(ClientResources.I_WAIT_ASYNC_SENDS_COMPLETE_PRODUCER,
                                                String.valueOf(remaining), producer);
                                        sessionLogger.log(Level.FINE, msg);
                                        loggered = true;
                                    }
                                    asyncSendLock.wait(remaining);
                                } catch (InterruptedException e) {
                                }
                                remaining = endtime - System.currentTimeMillis();
                                break;
                            }
                        }
                    }
                    firstround = false;
                }
            }
        }
    }

    public void _stopFromRA() throws JMSException {
        synchronized (raEndpointSyncObj) {
            /**
             * EndpointConsumer.stopMessageConsumer() calls this method to stop the SessionReader.
             *
             * Do not need to wait because the caller must wait for OnMessageRunners to ruturn. bug ID 6526078 - MQ thread deadlock
             * during AS shutdown.
             */
            stop(false);
        }
    }

    protected void stop() throws JMSException {
        stop(true);
    }

    /**
     * Called by Connection.stop(), Session.close().
     */
    protected void stop(boolean doWait) throws JMSException {

        if (isStopped || isClosed) {
            return;
        }

        checkPermission();

        synchronized (sessionSyncObj) {
            sessionQueue.stop(doWait);

            serverSessionRunner.serverSessionStop();

            // lock receive queue for each consumer
            // MessageConsumerImpl consumer = null;
            // Enumeration enum = consumers.elements();
            // while (enum.hasMoreElements()) {
            // consumer = (MessageConsumerImpl) enum.nextElement();
            // consumer.stop();
            // }

            MessageConsumerImpl[] consumerArray = (MessageConsumerImpl[]) consumers.values().toArray(new MessageConsumerImpl[0]);

            for (int i = 0; i < consumerArray.length; i++) {

                if (doWait) {
                    consumerArray[i].stop();
                } else {
                    consumerArray[i].stopNoWait();
                }
            }

            isStopped = true;
        }
    }

    protected void setConnectionConsumer(ConnectionConsumerImpl cc) {
        connectionConsumer = cc;
    }

    protected void resetServerSessionRunner() {
        resetServerSessionRunner(true);
    }

    /**
     * @param timeout in seconds
     */
    protected void resetServerSessionRunner(boolean resetState) {
        ServerSessionRunner ssr = serverSessionRunner;
        if (ssr != null) {
            ssr.reset(resetState);
        }
    }

    /**
     * Reset this session. 1. Stop session reader. 2. Clear session queue. 3. Clear Consumer queues. 4. Clear
     * unAckedMessageQueue. 5. Restart session reader.
     *
     * bug ID 6302418 -- there is really no reason to synchronize this method.
     */
    protected /** synchronized **/
    void reset() throws JMSException {

        // 1. Stop session reader. Wait does not provide any benefit here.
        try {
            // fix for bug 6578150 - session.close() takes too long
            // we are in recover state, the world is stopped already
            // stop(false);

            // 2. Clear session queue. -- PRIORITYQ
            sessionQueue.clear();
            // 3. Clear Consumer queue.
            MessageConsumerImpl consumer = null;
            Enumeration enum2 = consumers.elements();
            while (enum2.hasMoreElements()) {
                consumer = (MessageConsumerImpl) enum2.nextElement();
                // PRIORITYQ
                consumer.receiveQueue.clear();
            }
            // 4. Clear unacked message queue
            if (unAckedMessageQueue != null) {
                unAckedMessageQueue.removeAllElements();
            }

            // 5.Restart session reader
            // we did not stop
            // start();

            // 6. clean up the consumers table. The objects will be
            // re-constructed
            // in ConnectionRecover. -- bug ID 6311895.
            consumers.clear();
            // 7. reset this flag to false since we will re-create all the
            // sessions/consumers.
            this.remore_broker_failed = false;

            // 8. HACC -- set reset flag for serversession state.
            if (serverSessionRunner != null) {
                serverSessionRunner.reset();
            }

            closeBrowserConsumers();

        } finally {
            sessionQueue.start();
            this.isStopped = false;
        }
    }

    protected void recreateSession() throws JMSException {
        String emsg = AdministeredObject.cr.getKString(AdministeredObject.cr.X_CONNECTION_FAILOVER);
        JMSException ex = new JMSException(emsg, ClientResources.X_CONNECTION_FAILOVER);
        AsyncSendCallback cb = null;
        synchronized (asyncSendLock) {
            Iterator<AsyncSendCallback> itr = asyncSends.iterator();
            while (itr.hasNext()) {
                cb = itr.next();
                cb.processException(ex);
            }
        }

        if (connection.getBrokerProtocolLevel() >= PacketType.VERSION350) {
            protocolHandler.createSession(this);
        }

        if (isTransacted) {

            if (connection.isConnectedToHABroker) {
                // resolve the state of transaction.
                // verifyHATransaction();
            } else {
                // Start a new transaction.
                transaction = new Transaction(this, true);
            }
        }

        failoverOccurred = true;
    }

    protected /** synchronized **/
    void start() throws JMSException {

        synchronized (sessionSyncObj) {
            // unlock session queue
            sessionQueue.start();

            serverSessionRunner.serverSessionRun();

            // unlock receive queue for each consumer
            /*
             * MessageConsumerImpl consumer = null; Enumeration enum = consumers.elements(); while (enum.hasMoreElements()) {
             * consumer = (MessageConsumerImpl) enum.nextElement(); consumer.start(); }
             */

            MessageConsumerImpl[] consumerArray = (MessageConsumerImpl[]) consumers.values().toArray(new MessageConsumerImpl[0]);

            for (int i = 0; i < consumerArray.length; i++) {
                consumerArray[i].start();
            }

            isStopped = false;
        }
    }

    /**
     * Throws IllegalStateException if called from message listener.
     */
    protected void checkPermission() throws JMSException {

        if (Thread.currentThread() == sessionReader.sessionThread || Thread.currentThread() == serverSessionRunner.getCurrentThread()) {
            String errorString = AdministeredObject.cr.getKString(ClientResources.X_ILLEGAL_STATE);

            javax.jms.IllegalStateException jmse = new javax.jms.IllegalStateException(errorString, ClientResources.X_ILLEGAL_STATE);

            ExceptionHandler.throwJMSException(jmse);
        }

    }

    protected void checkPermissionForAsyncSend() throws JMSException {
        if (asyncSendCBProcessor != null && asyncSendCBProcessor.isTimerThread(Thread.currentThread())) {
            String errorString = AdministeredObject.cr.getKString(ClientResources.X_ILLEGAL_STATE);
            javax.jms.IllegalStateException jmse = new javax.jms.IllegalStateException(errorString, ClientResources.X_ILLEGAL_STATE);
            ExceptionHandler.throwJMSException(jmse);
        }
    }

    /*
     * This method is called from the RA and serializes acknowledgement to avoid any MT violations on the Session which by
     * rule can only be operated on by a single thread 'at a time' Since it has to do things almost exactly like a
     * transacted session but isn't really one, the code from acknowledge() is reproduced here XXX:candidate to be
     * refactored
     */
    public void acknowledgeUndeliverableFromRAEndpoint(MessageImpl message, XAResourceForRA xar, boolean sendToDMQ) throws JMSException {
        synchronized (raEndpointSyncObj) {

            // do this for flow control
            readChannel.flowControl.messageDelivered();

            Consumer consumer = (Consumer) consumers.get(Long.valueOf(message.getInterestID()));

            // We know it *does not* have a ConnectionConsumer
            /*
             * if (consumer == null) { // It may be a ConnectionConsumer... consumer = connection.interestTable.getConsumer( new
             * Long(message.getInterestID())); }
             */

            readChannel.flowControl.messageDelivered(consumer);
            TEST_rxCount++;

            try {
                setInSyncState();

                // We do not care about rollback since if transacted
                // it is in an XA transaction and the rollback will be via XA

                // We get the transactionID from the XAResource that was
                // passed in
                // System.out.println("\t\tSessionImpl:acknowledgeFromRA-msg="+message.toString());
                if (xar != null && xar.started()) {
                    synchronized (xar) {
                        // System.out.println("\t\tSessionImpl:ackWxar:txID="+xar.getTransactionID()+":bkrSessionId="+brokerSessionID);
                        ackPkt.setTransactionID(xar.getTransactionID());
                        // System.out.println("\t\tSessionImpl:ackWxar:txID="+xar.getTransactionID()+"...done:bkrSessionId="+brokerSessionID);
                    }
                } else {
                    // System.out.println("\t\tSessionImpl:ackWithoutxar:bkrSessionId="+brokerSessionID);
                    ackPkt.setTransactionID(0L);
                    // System.out.println("\t\tSessionImpl:ackWithoutxar...done:bkrSessionId="+brokerSessionID);
                }
                writeMessageID(message);
                doAcknowledgeUndeliverable(true, sendToDMQ);
                // System.out.println("\t\tSessionImpl:doAcknowledge...done:bkrSessionId="+brokerSessionID);

            } finally {
                releaseInSyncState();
            }
        }
    }

    /*
     * This method is called from the RA and serializes acknowledgement to avoid any MT violations on the Session which by
     * rule can only be operated on by a single thread 'at a time' Since it has to do things almost exactly like a
     * transacted session but isn't really one, the code from acknowledge() is reproduced here XXX:candidate to be
     * refactored
     */
    public void acknowledgeFromRAEndpoint(MessageImpl message, XAResourceForRA xar) throws JMSException {
        synchronized (raEndpointSyncObj) {

            if (sessionLogger.isLoggable(Level.FINER)) {
                logMessageDelivered(message);
            }

            // do this for flow control
            readChannel.flowControl.messageDelivered();

            Consumer consumer = (Consumer) consumers.get(Long.valueOf(message.getInterestID()));

            // We know it *does not* have a ConnectionConsumer
            /*
             * if (consumer == null) { // It may be a ConnectionConsumer... consumer = connection.interestTable.getConsumer( new
             * Long(message.getInterestID())); }
             */

            readChannel.flowControl.messageDelivered(consumer);
            TEST_rxCount++;

            boolean requiresAckFromBroker = true;
            Hashtable originalProps = null;
            try {
                setInSyncState();

                // We do not care about rollback since if transacted
                // it is in an XA transaction and the rollback will be via XA

                // We get the transactionID from the XAResource that was
                // passed in
                // System.out.println("\t\tSessionImpl:acknowledgeFromRA-msg="+message.toString());
                if (xar != null && xar.started()) {
                    synchronized (xar) {
                        // System.out.println("\t\tSessionImpl:ackWxar:txID="+xar.getTransactionID()+":bkrSessionId="+brokerSessionID);
                        ackPkt.setTransactionID(xar.getTransactionID());
                        // System.out.println("\t\tSessionImpl:ackWxar:txID="+xar.getTransactionID()+"...done:bkrSessionId="+brokerSessionID);
                    }
                    // performance optimisation
                    // Do not wait for reply from broker when
                    // sending message acknowledgments in a transaction.
                    // Reliability will be ensured by blocking on commit.
                    requiresAckFromBroker = !noBlockUntilTxnCompletes;
                } else {
                    // System.out.println("\t\tSessionImpl:ackWithoutxar:bkrSessionId="+brokerSessionID);
                    ackPkt.setTransactionID(0L);
                    // System.out.println("\t\tSessionImpl:ackWithoutxar...done:bkrSessionId="+brokerSessionID);
                    if (!isTransacted && acknowledgeMode == Session.AUTO_ACKNOWLEDGE) {
                        if ((consumer != null && !consumer.getDurable()) || noBlockOnAutoAckNPTopics) {
                            /*
                             * performance optimisation Normally block when acknowledging messages to avoid duplicates in the event of provider
                             * failure. However, duplicates are not a problem for NP topic sessions, as messages will not be re-dispatched if client
                             * reconnects after failure.
                             */
                            Destination d = message.getJMSDestination();
                            if (!message._getPersistent() && d instanceof Topic) {
                                requiresAckFromBroker = false;
                            }
                        }
                    }
                }
                writeMessageID(message);

                if (message.getClientRetries() > 0) {
                    try {
                        originalProps = ackPkt.getProperties();
                    } catch (Exception e) {
                    }
                    Hashtable props = new Hashtable();
                    props.put(ConnectionMetaDataImpl.JMSXDeliveryCount, Integer.valueOf(message.getClientRetries()));
                    ackPkt.setProperties(props);
                }

                doAcknowledge(requiresAckFromBroker);
                // System.out.println("\t\tSessionImpl:doAcknowledge...done:bkrSessionId="+brokerSessionID);

            } finally {
                if (originalProps != null) {
                    ackPkt.setProperties(originalProps);
                }
                releaseInSyncState();
            }
        }
    }

    public void acknowledgeFromRAEndpoint(MessageImpl message) throws JMSException {
        synchronized (raEndpointSyncObj) {
            acknowledge(message);
        }
    }

    public void _appTransactedAck(MessageImpl message) throws JMSException {
        Consumer consumer = (Consumer) consumers.get(Long.valueOf(message.getInterestID()));
        if (consumer == null) {
            String errorString = AdministeredObject.cr.getKString(AdministeredObject.cr.X_CONSUMER_CLOSED);
            throw new JMSException(errorString, AdministeredObject.cr.X_CONSUMER_CLOSED);
        }
        if (!(consumer instanceof MessageConsumerImpl)) { // should not happen
            throw new JMSException("Operation not supported for consumer type: " + consumer.getClass().getName());
        }
        acknowledge(message);

        ((MessageConsumerImpl) consumer).lastDeliveredID = message.getMessageID();

    }

    protected void doPrefetch(Consumer consumer) {
        readChannel.flowControl.messageDelivered();
        readChannel.flowControl.messageDelivered(consumer);
        TEST_rxCount++;
    }

    protected void acknowledge(MessageImpl message) throws JMSException {
        acknowledge(message, true);
    }

    /*
     * This method is called after MessageListener.onMessage() is returned or receive() call returned.
     *
     * This method dispatch the ack action based on the session ack mode.
     */
    protected void acknowledge(MessageImpl message, boolean prefetch) throws JMSException {

        if (sessionLogger.isLoggable(Level.FINER)) {

            // String pktType = PacketType.getString( ((MessageImpl) message).getPacket().getPacketType());

            // String param = pktType + "," +
            // ", ConsumerID=" + message.getInterestID() +
            // ", " + toString();

            this.logMessageDelivered(message);

        }

        if (prefetch) {
            // do this for flow control
            readChannel.flowControl.messageDelivered();
        }

        Consumer consumer = (Consumer) consumers.get(Long.valueOf(message.getInterestID()));

        if (consumer == null) {
            // It may be a ConnectionConsumer...
            consumer = connection.interestTable.getConsumer(Long.valueOf(message.getInterestID()));
        }

        if (prefetch) {
            readChannel.flowControl.messageDelivered(consumer);
            TEST_rxCount++;
        }

        try {
            setInSyncState();

            if (isTransacted) {
                transactedAcknowledge(message);
            } else { // non-transacted
                switch (acknowledgeMode) {
                case Session.AUTO_ACKNOWLEDGE:
                    autoAcknowledge(message, (consumer == null ? true : consumer.getDurable()));
                    break;
                case Session.CLIENT_ACKNOWLEDGE:
                    prepareClientAcknowledge(message);
                    break;
                case Session.DUPS_OK_ACKNOWLEDGE:
                    if (dupsOkAckOnTimeout) {
                        syncedDupsOkAcknowledge(message);
                    } else {
                        dupsOkAcknowledge(message);
                    }
                    break;
                case com.sun.messaging.jms.Session.NO_ACKNOWLEDGE:
                    // NO_ACKNOWLEDGE mode -- do nothing
                    break;
                default:
                    autoAcknowledge(message, (consumer == null ? true : consumer.getDurable()));
                    break;
                } // switch
            }

        } catch (JMSException jmse) {

            // we only care about auto/dups-ok mode
            if ((isTransacted == false) && (acknowledgeMode == Session.AUTO_ACKNOWLEDGE || acknowledgeMode == Session.DUPS_OK_ACKNOWLEDGE)) {

                // check if this is caused by the remote broker failure.
                if (isRemoteException(jmse)) {
                    // recreate consumers in the session
                    this.recreateConsumers();

                    ExceptionHandler.throwRemoteAcknowledgeException(jmse, ClientResources.X_AUTO_ACK_FAILED_REMOTE);

                    // construct the precise exception
                    // String errorString = AdministeredObject.cr.getKString(
                    // ClientResources.X_AUTO_ACK_FAILED_REMOTE);

                    // JMSException newjmse = new com.sun.messaging.jms.JMSException(errorString,
                    // ClientResources.X_AUTO_ACK_FAILED_REMOTE);

                    // set exception link
                    // newjmse.setLinkedException(jmse);
                    // throw the exception
                    // ExceptionHandler.throwJMSException(newjmse);
                }
            }

            // re-throw the old one.
            throw jmse;

        } finally {
            releaseInSyncState();
        }
    }

    protected void acknowledgeExpired(MessageImpl message) throws JMSException {
        acknowledgeExpired(message, true);
    }

    protected void acknowledgeExpired(MessageImpl message, boolean prefetch) throws JMSException {
        if (sessionLogger.isLoggable(Level.FINER)) {
            this.logMessageExpired(message);
        }
        acknowledgeDeadMessage(message, prefetch, 1 /* expired */);
    }

    protected void acknowledgeUndeliverable(MessageImpl message) throws JMSException {
        if (sessionLogger.isLoggable(Level.FINER)) {
            this.logMessageUndeliverable(message);
        }
        acknowledgeDeadMessage(message, true, 0 /* undeliverable */);
    }

    protected void acknowledgeDeadMessage(MessageImpl message, boolean prefetch, int deadReason) throws JMSException {

        synchronized (raEndpointSyncObj) {

            if (prefetch) {
                readChannel.flowControl.messageDelivered();
            }

            Consumer consumer = (Consumer) consumers.get(Long.valueOf(message.getInterestID()));

            if (consumer == null) {
                // It may be a ConnectionConsumer...
                consumer = connection.interestTable.getConsumer(Long.valueOf(message.getInterestID()));
            }

            if (prefetch) {
                readChannel.flowControl.messageDelivered(consumer);
                TEST_rxCount++;
            }

            try {
                expireDos.writeLong(message.getInterestID());
                message.getMessageID().writeID(expireDos);
                expireDos.flush();
                expireBos.flush();
                expirePkt.setMessageBody(expireBos.toByteArray());
                ackPkt.setSendAcknowledge(false);
                protocolHandler.acknowledgeUndeliverable(expirePkt, true, deadReason);

            } catch (Exception e) {
                String destName = "";
                try {
                    if (consumer != null) {
                        destName = consumer.getDestName();
                    } else {
                        destName = message.getJMSDestination().toString();
                    }
                } catch (Exception e1) {
                }
                Object args[] = { message.getMessageID(), destName, message.getInterestID(), e.getMessage() };
                String ecode = (deadReason == 1 ? ClientResources.X_EXPIRE_MSG_TO_DMQ : ClientResources.X_UNDELIVERABLE_MSG_TO_DMQ);
                String estr = AdministeredObject.cr.getKString(ecode, args);
                JMSException jmse = new JMSException(estr, ecode);
                jmse.setLinkedException(e);
                throw jmse;
            } finally {
                expireBos.reset();
            }

        } // synchronized
    }

    private void logMessageExpired(MessageImpl message) {
        logMessage(message, ClientResources.I_EXPIRED_MSG_BEFORE_DELIVER_TO_CONSUMER);
    }

    private void logMessageUndeliverable(MessageImpl message) {
        logMessage(message, ClientResources.I_UNDELIVERABLE_MSG);
    }

    private void logMessageDelivered(MessageImpl message) {
        logMessage(message, ClientResources.I_CONSUMER_MESSAGE_DELIVERED);
    }

    private void logMessage(MessageImpl message, String key) {
        try {
            if (sessionLogger.isLoggable(Level.FINER)) {
                String param = makeDebugStringForMessage(message);
                sessionLogger.log(Level.FINER, key, param);
                if (sessionLogger.isLoggable(Level.FINEST)) {
                    param = "MQTrace=MessageConsumer" + ", ConsumerID=" + message.getInterestID() + ", Message=" + message.toString();
                    sessionLogger.log(Level.FINEST, key, param);
                }
            }

        } catch (Exception ex) {
            ex.printStackTrace();
        }
    }

    private String makeDebugStringForMessage(MessageImpl message) {
        try {

            com.sun.messaging.Destination mqDest = (com.sun.messaging.Destination) message.getJMSDestination();
            String domain = (mqDest.isQueue() ? "Queue:" : "Topic:");

            String pktType = PacketType.getString(message.getPacket().getPacketType());

            return ("MQTrace=MessageConsumer" + ", ThreadID=" + Thread.currentThread().getId() + ", ClientID=" + this.connection.getClientID()
                    + ", ConnectionID=" + this.connection.getConnectionID() + ", SessionID=" + this.getBrokerSessionID() + ", ConsumerID="
                    + message.getInterestID() + ", Destination=" + domain + mqDest.getName() + ", MessageID=" + message.getJMSMessageID()
                    + ", MessageType=" + pktType);

        } catch (Exception e) {
            e.printStackTrace();
            return "[MessageID=" + message.getMessageID() + ", ConsumerID=" + message.getInterestID() + "]";
        }
    }

    /**
     * auto acknowledge.
     *
     * @param message the message to be acknowledged.
     */
    protected void autoAcknowledge(MessageImpl message, boolean isdurable) throws JMSException {
        // param true if require broker to ack back.
        writeMessageID(message);
        boolean requireAckFromBroker = true;
        if (!isdurable || noBlockOnAutoAckNPTopics) {
            // performance optimisation
            // Normally block when acknowledging messages
            // to avoid duplicates in the event of provider failure.
            // However, duplicates are not a problem for NP topic sessions,
            // as messages will not be re-dispatched if client reconnects after failure.
            //
            Destination d = message.getJMSDestination();
            if (!message._getPersistent() && d instanceof Topic) {
                requireAckFromBroker = false;
            }
        }

        doAcknowledge(requireAckFromBroker);
    }

    /**
     * For transacted session, each message is acknowledged by calling this method.
     *
     * @param message the message to be acknowledged.
     */
    protected void transactedAcknowledge(MessageImpl message) throws JMSException {
        try {
            // put on ack list in case we have to rollback.
            boolean isAddedToList = prepareTransactedAcknowledge(message);

            // if it is added to the list, we know this message is not
            // acked yet.
            if (isAddedToList) {
                ackPkt.setTransactionID(transaction.getTransactionID());
                writeMessageID(message);

                // performance optimisation
                // Do not wait for reply from broker when
                // sending message acknowledgments in a transaction.
                // Reliability will be ensured by blocking on commit.
                boolean requiresAckFromBroker = !noBlockUntilTxnCompletes;
                doAcknowledge(requiresAckFromBroker);
            }
        } catch (JMSException jmse) {

            // we only set the flag here. app needs to call Session.rollback() to
            // recreate consumer and flag will be cleared.
            if (jmse instanceof RemoteAcknowledgeException) {
                this.remore_broker_failed = true;
            }

            // re-throw exception
            throw jmse;
        }
    }

    /**
     * Write interestID and messageID to the byte array.
     *
     * @param message the message to be acked/redelivered.
     */
    protected void writeMessageID(MessageImpl message) throws JMSException {
        try {
            // XXX PROTOCOL2.1
            dos.writeLong(message.getInterestID());
            message.getMessageID().writeID(dos);
        } catch (IOException e) {
            ExceptionHandler.handleException(e, ClientResources.X_CAUGHT_EXCEPTION);
        }
    }

    protected void writeMessageID(UnAckedMessage message) throws JMSException {
        try {
            // XXX PROTOCOL2.1
            dos.writeLong(message.getConsumerID());
            message.getMessageID().writeID(dos);
        } catch (IOException e) {
            ExceptionHandler.handleException(e, ClientResources.X_CAUGHT_EXCEPTION);
        }
    }

    /**
     * Write interestID and messageID to the byte array.
     *
     * @param pkt the pkt to be acked/redelivered.
     */
    protected void writeMessageID(ReadOnlyPacket pkt) throws JMSException {
        try {
            // XXX PROTOCOL2.1
            dos.writeLong(pkt.getConsumerID());
            pkt.getSysMessageID().writeID(dos);
        } catch (IOException e) {
            ExceptionHandler.handleException(e, ClientResources.X_CAUGHT_EXCEPTION);
        }
    }

    /**
     * This actually writes ack to the broker
     *
     * @param requireAckFromBroker true if requires broker to ack back.
     */
    protected void doAcknowledgeUndeliverable(boolean requireAckFromBroker, boolean sendToDMQ) throws JMSException {

        try {
            dos.flush();
            bos.flush();

            // set message body
            ackPkt.setMessageBody(bos.toByteArray());

            // set bit if require broker to ack back.
            ackPkt.setSendAcknowledge(requireAckFromBroker);
            // write ack packet
            protocolHandler.acknowledgeUndeliverable(ackPkt, sendToDMQ);

            TEST_ackCount++;

        } catch (IOException e) {
            ExceptionHandler.handleException(e, ClientResources.X_MESSAGE_ACK);
        } finally {
            // reset buf count to 0
            bos.reset();
            // reset counter
            ackCounter = 0;
            // reset time stamp
            dupsOkTimestamp = 0;
        }
    }

    /**
     * This actually writes ack to the broker
     *
     * @param requireAckFromBroker true if requires broker to ack back.
     */
    protected void doAcknowledge(boolean requireAckFromBroker) throws JMSException {

        try {
            dos.flush();
            bos.flush();

            // set message body
            ackPkt.setMessageBody(bos.toByteArray());

            // set bit if require broker to ack back.
            ackPkt.setSendAcknowledge(requireAckFromBroker);

            // check failover flag again before acknowledge to broker.
            // bug 6309751 - Unexpected Broker Internal Error during fail over.
            this.checkFailOver();

            protocolHandler.acknowledge(ackPkt);

            TEST_ackCount++;

        } catch (IOException e) {
            ExceptionHandler.handleException(e, ClientResources.X_MESSAGE_ACK);
        } finally {
            // reset buf count to 0
            bos.reset();
            // reset counter
            ackCounter = 0;
            // reset time stamp
            dupsOkTimestamp = 0;
        }
    }

    /**
     * DupsOkAcknowledge mode. Called by Session.acknowledge().
     *
     * @param message the message to be acked.
     */
    protected void dupsOkAcknowledge(MessageImpl message) throws JMSException {

        addMessageToAckList(message);

        /**
         * Acknowledge when reached limit or sessionQueue is empty. This is the minimum check required to ensure messages are
         * acked. More sophicated ack may be used later.
         */
        // if ( ackCounter == dupsOkLimit || sessionQueue.isEmpty() ) {
        if (dupsOkShouldAcknowledge()) {
            dupsOkCommitAcknowledge();
            // dequeue ( unAckedMessageQueue );
            // doAcknowledge(false);
        }
    }

    protected void dupsOkCommitAcknowledge() throws JMSException {

        if (debug) {
            Debug.println("***** dups ok committing ack .... size: " + ackCounter);
        }

        dequeueUnAckedMessages();
        doAcknowledge(false);
    }

    // called if session is dupsOkAckOnTimeout mode.
    protected void syncedDupsOkAcknowledge(MessageImpl message) throws JMSException {

        // sync on dupsOkSyncObj to prevent deadlock - bugid 4987018
        synchronized (dupsOkSyncObj) {
            // set timestamp if this is the first unacked msg.
            if (ackCounter == 0) {
                dupsOkTimestamp = System.currentTimeMillis();
            }

            dupsOkAcknowledge(message);
        }
    }

    // called by consumer reader.
    protected void syncedDupsOkCommitAcknowledge() throws JMSException {

        // sync on dupsOkSyncObj - bugid 4987018
        synchronized (dupsOkSyncObj) {
            if (ackCounter > 0) {
                dupsOkCommitAcknowledge();
            }
        }
    }

    protected boolean dupsOkShouldAcknowledge() {

        if (dupsOkAckOnTimeout) {
            // time elapsed since first unacked message was received.
            boolean timeToAck = (System.currentTimeMillis() - dupsOkTimestamp) >= dupsOkAckTimeout;
            return ((ackCounter == dupsOkLimit) || timeToAck);
        } else if (dupsOkAckOnEmptyQueue) {
            return (ackCounter == dupsOkLimit || sessionQueue.isEmpty());
        } else { // ack on limit
            return (ackCounter == dupsOkLimit);
        }
    }

    /**
     * called by prepareClientAcknowledge() and prepareTransactedAcknowledge().
     *
     * Do NOT require to synchronize this method because ONLY one thread can call this method at a time.
     */
    protected boolean addMessageToAckList(MessageImpl message) throws JMSException {

        boolean isAddedToList = false;

        if (message != null && message.getIsOnAckList() == false) {
            message.setIsOnAckList(true);
            // unAckedMessageQueue.addElement(message);
            // use light weight obj instead -- bug 4934856
            UnAckedMessage unacked = new UnAckedMessage(message);
            unAckedMessageQueue.addElement(unacked);

            ackCounter++;

            isAddedToList = true;
        }

        return isAddedToList;
    }

    /**
     * Remove message from ack list. Called when consumer is closed. This removes unacked messages on the list if any. --
     * 4934856
     */
    protected void removeMessageFromAckList(UnAckedMessage unacked) {
        // message.setIsOnAckList (false);
        unAckedMessageQueue.removeElement(unacked);
        ackCounter--;
    }

    /**
     * For client ack mode. Called by Session.acknowledge().
     *
     * @param message the message to be acked.
     */
    protected /* synchronized */ void prepareClientAcknowledge(MessageImpl message) throws JMSException {
        // if ( message.getIsOnAckList() == false ) {
        addMessageToAckList(message);
        if (isAckLimited) {
            checkClientAckLimit();
        }
        // }
    }

    /**
     * Method to check client unacknowledged method limit. Used by client acknowledge mode.
     */
    protected void checkClientAckLimit() throws JMSException {
        if (ackCounter > ackLimit) {
            String errorString = AdministeredObject.cr.getKString(ClientResources.X_CLIENT_ACK_LIMIT);
            Debug.println(errorString);
            // throw new JMSException (errorString, ClientResources.X_CLIENT_ACK_LIMIT);
        }
    }

    protected boolean prepareTransactedAcknowledge(MessageImpl message) throws JMSException {

        boolean isAddedToList = false;

        isAddedToList = addMessageToAckList(message);

        if (isAckLimited) {
            checkTransactedAckLimit();
        }

        return isAddedToList;
    }

    /**
     * Check transacted unack message limit. Used by transacted session.
     */
    protected void checkTransactedAckLimit() throws JMSException {
        // check unacked limit
        if (ackCounter > ackLimit) {
            String errorString = AdministeredObject.cr.getKString(ClientResources.X_COMMIT_LIMIT);
            Debug.println(errorString);
            // throw new JMSException (errorString, ClientResources.X_COMMIT_LIMIT);
        }
    }

    /*
     * (non-Javadoc)
     *
     * @see com.sun.messaging.jmq.jmsclient.ContextableSession#clientAcknowledge()
     */
    @Override
    public void clientAcknowledge() throws JMSException {

        if (getAcknowledgeMode() != Session.CLIENT_ACKNOWLEDGE) {
            return;
        }

        if (failoverOccurred) {
            // "Cannot acknowledge messages due to provider connection failover.
            // "Subsequent acknowledge calls will also fail until the application calls session.recover()."
            String errorString = AdministeredObject.cr.getKString(ClientResources.X_CLIENT_ACK_FAILOVER_OCCURRED);
            JMSException jmse = new JMSException(errorString, ClientResources.X_CLIENT_ACK_FAILOVER_OCCURRED);
            ExceptionHandler.throwJMSException(jmse);
        }

        checkSessionState();

        if (unAckedMessageQueue.size() > 0) {
            dequeueUnAckedMessages();
            // write the list to the broker.
            doClientAcknowledge();
        }
    }

    /**
     * Called by Message.acknowledge(). This method could be called from two different threads. One from SessionReader
     * thread, and the other from the user thread. If called from SessionReader thread, the message is likely to be not on
     * the ack list yet. We need to check if the current message is on the list. If not, it is added to the list.
     *
     * Only messages up to the current message should be acknowledged. There may be messages in the unAckedMessageQueue
     * (messages has been delivered to the client) but the client decides not to acknowledge for whatever reasons. We should
     * leave those messages in the queue according to the spec.
     */
    protected /* synchronized */ void clientAcknowledge(MessageImpl message) throws JMSException {

        if (failoverOccurred) {
            // "Cannot acknowledge messages due to provider connection failover.
            // "Subsequent acknowledge calls will also fail until the application calls session.recover()."
            String errorString = AdministeredObject.cr.getKString(ClientResources.X_CLIENT_ACK_FAILOVER_OCCURRED);
            JMSException jmse = new JMSException(errorString, ClientResources.X_CLIENT_ACK_FAILOVER_OCCURRED);
            ExceptionHandler.throwJMSException(jmse);
        }

        /**
         * When message consumer is closed, doAcknowledge flag is set to false. We(George, Amy and Chiaming) decided to throw
         * exception in this case.
         */
        // XXX:tharakan revisit since Session changes should now allow message to be acknowledged
        // XXX:tharakan after the consumer is closed.
        // if ( message.doAcknowledge == false ) {
        // String errorString = AdministeredObject.cr.getKString(AdministeredObject.cr.X_CLIENT_ACKNOWLEDGE);
        // throw new javax.jms.IllegalStateException (errorString, AdministeredObject.cr.X_CLIENT_ACKNOWLEDGE);
        // }
        this.checkClientAckMessage(message);

        checkSessionState();

        if (isTransacted == false) {
            // check if on the list, if not, add this message to the list
            prepareClientAcknowledge(message);

            // The following code is to write unacked message IDs to byte array.
            // The unAcked queue is searched sequentially until the message ID
            // in the queue matches the current acking message ID.
            // MessageImpl unAckedMessage = null;
            // boolean found = false;
            // while ( !found ) {
            // make this simple and stupid. do not disturb the order of
            // messages in the unAcked queue.
            // unAckedMessage = (MessageImpl) unAckedMessageQueue.firstElement();
            // writeMessageID ( unAckedMessage );
            // remove since it has been moved to the out going array.
            // unAckedMessageQueue.removeElementAt(0);

            // if ( message.messageID.equals(unAckedMessage.messageID) ) {
            // found = true;
            // }
            // }

            /**
             * JMS 1.0.2 (Update b) changed the meaning of Message.acknowledge() From ackowledge all messages consumed upto and
             * including the current one in the session to acknowledge all messages consumed in the session
             */
            if (unAckedMessageQueue.size() > 0) {
                dequeueUnAckedMessages();
                // write the list to the broker.
                // doAcknowledge(true);
                doClientAcknowledge();
            }
        }
    }

    /**
     * Called by Message.acknowledgeThisMessage(). This method could be called from two different threads. One from
     * SessionReader thread, and the other from the user thread. If called from SessionReader thread, the message is likely
     * to be not on the ack list yet. We need to check if the current message is on the list. If not, it is added to the
     * list.
     *
     * Only this message should be acknowledged. All other message in the unAckedMessageQueue should be left unacknowledged
     */
    protected /* synchronized */ void clientAcknowledgeThisMessage(MessageImpl message) throws JMSException {

        /**
         * When message consumer is closed, doAcknowledge flag is set to false. We(George, Amy and Chiaming) decided to throw
         * exception in this case.
         */
        // XXX:tharakan revisit since Session changes should now allow message to be acknowledged
        // XXX:tharakan after the consumer is closed.
        // if ( message.doAcknowledge == false ) {
        // String errorString = AdministeredObject.cr.getKString(AdministeredObject.cr.X_CLIENT_ACKNOWLEDGE);
        // throw new javax.jms.IllegalStateException (errorString, AdministeredObject.cr.X_CLIENT_ACKNOWLEDGE);
        // }
        this.checkClientAckMessage(message);

        checkSessionState();

        if (isTransacted == false) {
            // check if on the list, if not, add this message to the list
            prepareClientAcknowledge(message);
            // bug 4934856
            UnAckedMessage unAckedMessage = null;
            // kiss - linear search for the messageID
            for (int i = 0; i < unAckedMessageQueue.size(); i++) {
                unAckedMessage = (UnAckedMessage) unAckedMessageQueue.elementAt(i);
                if (message.messageID.equals(unAckedMessage.getMessageID())) {
                    // write the message ID
                    writeMessageID(unAckedMessage);
                    // remove it from the unacked list
                    unAckedMessageQueue.removeElementAt(i);
                    // write the acknowledge list (one message) to the broker
                    // doAcknowledge(true);
                    doClientAcknowledge();
                    return;
                }
            }
        }
    }

    /**
     * Called by Message.acknowledgeUpThroughThisMessage(). This method could be called from two different threads. One from
     * SessionReader thread, and the other from the user thread. If called from SessionReader thread, the message is likely
     * to be not on the ack list yet. We need to check if the current message is on the list. If not, it is added to the
     * list.
     *
     * Only messages up to the current message should be acknowledged. There may be messages in the unAckedMessageQueue
     * (messages has been delivered to the client) but the client decides not to acknowledge for whatever reasons. We should
     * leave those messages in the queue.
     */
    protected /* synchronized */ void clientAcknowledgeUpThroughThisMessage(MessageImpl message) throws JMSException {

        // Messages cannot be acknowledged after connection failover.
        // Reject client acknowledgements until the application calls
        // recover()...
        if (failoverOccurred) {
            String errorString = AdministeredObject.cr.getKString(ClientResources.X_CLIENT_ACK_FAILOVER_OCCURRED);
            JMSException jmse = new JMSException(errorString, ClientResources.X_CLIENT_ACK_FAILOVER_OCCURRED);

            ExceptionHandler.throwJMSException(jmse);
        }

        /**
         * When message consumer is closed, doAcknowledge flag is set to false. We(George, Amy and Chiaming) decided to throw
         * exception in this case.
         */
        // XXX:tharakan revisit since Session changes should now allow message to be acknowledged
        // XXX:tharakan after the consumer is closed.
        // if ( message.doAcknowledge == false ) {
        // String errorString = AdministeredObject.cr.getKString(AdministeredObject.cr.X_CLIENT_ACKNOWLEDGE);
        // throw new javax.jms.IllegalStateException (errorString, AdministeredObject.cr.X_CLIENT_ACKNOWLEDGE);
        // }
        this.checkClientAckMessage(message);

        checkSessionState();

        if (isTransacted == false) {
            // check if on the list, if not, add this message to the list
            prepareClientAcknowledge(message);

            // check if the message is in the unacked queue.
            if (isMessageInUnAckedQueue(message)) {

                // The following code is to write unacked message IDs to byte array.
                // The unAcked queue is searched sequentially until the message ID
                // in the queue matches the current acking message ID.
                UnAckedMessage unAckedMessage = null;
                boolean found = false;
                while (!found) {
                    // make this simple and stupid. do not disturb the order of
                    // messages in the unAcked queue. -- bug 4934856
                    unAckedMessage = (UnAckedMessage) unAckedMessageQueue.firstElement();

                    writeMessageID(unAckedMessage);
                    // remove since it has been moved to the out going array.
                    unAckedMessageQueue.removeElementAt(0);

                    if (message.messageID.equals(unAckedMessage.getMessageID())) {
                        found = true;
                    }
                }

                // write the list to the broker.
                // doAcknowledge(true);
                doClientAcknowledge();
            }
        }
    }

    private void doClientAcknowledge() throws JMSException {

        if (this.remore_broker_failed) {

            ExceptionHandler.throwRemoteAcknowledgeException(null, ClientResources.X_CLIENT_ACK_FAILED_REMOTE);

            // String errorString = AdministeredObject.cr
            // .getKString(ClientResources.X_CLIENT_ACK_FAILED_REMOTE);

            // JMSException jmse = new com.sun.messaging.jms.JMSException(
            // errorString, ClientResources.X_CLIENT_ACK_FAILED_REMOTE);

            // throw the exception
            // ExceptionHandler.throwJMSException(jmse);
        }

        try {
            doAcknowledge(true);
        } catch (JMSException jmse) {

            if (isRemoteException(jmse)) {

                // set this flag so that no further client ack is allowed.
                this.remore_broker_failed = true;

                // throw remote ack failed exception
                ExceptionHandler.throwRemoteAcknowledgeException(jmse, ClientResources.X_CLIENT_ACK_FAILED_REMOTE);

                // rethrow
                // construct the precise exception
                // String errorString = AdministeredObject.cr
                // .getKString(ClientResources.X_CLIENT_ACK_FAILED_REMOTE);

                // JMSException newjmse = new com.sun.messaging.jms.JMSException(
                // errorString, ClientResources.X_CLIENT_ACK_FAILED_REMOTE);

                // set exception link
                // newjmse.setLinkedException(jmse);
                // throw the exception
                // ExceptionHandler.throwJMSException(newjmse);
            } else {
                // no-op, re-throw the old exception
                throw jmse;
            }
        }
    }

    protected boolean isMessageInUnAckedQueue(MessageImpl message) throws JMSException {
        boolean inQueue = false;
        // 4934856
        UnAckedMessage unAckedMessage = null;
        int size = unAckedMessageQueue.size();

        for (int i = 0; i < size; i++) {
            unAckedMessage = (UnAckedMessage) unAckedMessageQueue.elementAt(i);
            if (message.messageID.equals(unAckedMessage.getMessageID())) {
                inQueue = true;
                // break the loop
                i = size;
            }
        }

        return inQueue;
    }

    /**
     * Check if session is closed.
     *
     * @throws IllegalStateException if session is closed.
     */
    protected void checkSessionState() throws JMSException {
        if (isClosed) {
            String errorString = AdministeredObject.cr.getKString(ClientResources.X_SESSION_CLOSED);

            JMSException jmse = new javax.jms.IllegalStateException(errorString, ClientResources.X_SESSION_CLOSED);

            ExceptionHandler.throwJMSException(jmse);
        }
    }

    protected void checkFailOver() throws JMSException {

        if (isTransacted && failoverOccurred) {
            String errorString = AdministeredObject.cr.getKString(ClientResources.X_TRANSACTION_INVALIDATED_FAILOVER);
            JMSException jmse = new javax.jms.JMSException(errorString, ClientResources.X_TRANSACTION_INVALIDATED_FAILOVER);

            ExceptionHandler.throwJMSException(jmse);
        }
    }

    /**
     * Create a BytesMessage. A BytesMessage is used to send a message containing a stream of uninterpreted bytes.
     *
     * @exception JMSException if JMS fails to create this message due to some internal error.
     */

    public BytesMessage createBytesMessage() throws JMSException {
        checkSessionState();
        // param true is to init DataOutputStream for writing.
        return new BytesMessageImpl(true);
    }

    /**
     * Create a MapMessage. A MapMessage is used to send a self-defining set of name-value pairs where names are Strings and
     * values are Java primitive types.
     *
     * @exception JMSException if JMS fails to create this message due to some internal error.
     */

    public MapMessage createMapMessage() throws JMSException {
        checkSessionState();
        return new MapMessageImpl();
    }

    /**
     * Create a Message. The Message interface is the root interface of all JMS messages. It holds all the standard message
     * header information. It can be sent when a message containing only header information is sufficient.
     *
     * @exception JMSException if JMS fails to create this message due to some internal error.
     */

    public Message createMessage() throws JMSException {
        checkSessionState();

        Message message = new MessageImpl();
        return message;
    }

    /**
     * Create an ObjectMessage. An ObjectMessage is used to send a message that containing a serializable Java object.
     *
     * @exception JMSException if JMS fails to create this message due to some internal error.
     */

    public ObjectMessage createObjectMessage() throws JMSException {
        checkSessionState();
        return new ObjectMessageImpl();
    }

    /**
     * Create an initialized ObjectMessage. An ObjectMessage is used to send a message that containing a serializable Java
     * object.
     *
     * @param object the object to use to initialize this message.
     *
     * @exception JMSException if JMS fails to create this message due to some internal error.
     */

    public ObjectMessage createObjectMessage(Serializable object) throws JMSException {
        checkSessionState();
        ObjectMessage objectMessage = new ObjectMessageImpl();
        objectMessage.setObject(object);

        return objectMessage;
    }

    /**
     * Create a StreamMessage. A StreamMessage is used to send a self-defining stream of Java primitives.
     *
     * @exception JMSException if JMS fails to create this message due to some internal error.
     */

    public StreamMessage createStreamMessage() throws JMSException {
        checkSessionState();
        // param true is to init ObjectOutputStream for writing.
        return new StreamMessageImpl(true);
    }

    /**
     * Create a TextMessage. A TextMessage is used to send a message containing a String.
     *
     * @exception JMSException if JMS fails to create this message due to some internal error.
     */

    public TextMessage createTextMessage() throws JMSException {
        checkSessionState();
        return new TextMessageImpl();
    }

    /**
     * Create an initialized TextMessage. A TextMessage is used to send a message containing a String.
     *
     * @param text the string used to initialize this message.
     *
     * @exception JMSException if JMS fails to create this message due to some internal error.
     */

    public TextMessage createTextMessage(String text) throws JMSException {
        checkSessionState();
        TextMessageImpl message = new TextMessageImpl();
        message.setText(text);
        return message;
    }

    /**
     * Is the session in transacted mode?
     *
     * @return true if in transacted mode
     *
     * @exception JMSException if JMS fails to return the transaction mode due to internal error in JMS Provider.
     */

    public boolean getTransacted() throws JMSException {
        checkSessionState();
        return isTransacted;
    }

    protected boolean getTransactedNoCheck() {
        return isTransacted;
    }

    /**
     * Gets value for how messages are acknowledged.
     *
     * @return one of the following values: <CODE>AUTO_ACKNOWLEDGE</CODE>, <CODE>CLIENT_ACKNOWLEDGE</CODE>,
     * <CODE>DUPS_OK_ACKNOWLEDGE</CODE>
     *
     * @exception JMSException if the JMS provider fails to return the acknowledge mode due to some internal error.
     *
     * @see Connection#createSession
     * @since 1.1
     */
    public int getAcknowledgeMode() throws JMSException {
        checkSessionState();
        if (isTransacted) {
            return 0;
        } else {
            return acknowledgeMode;
        }
    }

    /**
     * Commit all messages done in this transaction and releases any locks currently held.
     *
     * @exception JMSException if JMS implementation fails to commit the the transaction due to some internal error.
     * @exception TransactionRolledBackException if the transaction gets rolled back due to some internal error during
     * commit.
     * @exception IllegalStateException if method is not called by a transacted session.
     */

    public /* synchronized */ void commit() throws JMSException {

        checkSessionState();
        checkPermissionForAsyncSend();

        // XXX:GT TBF
        if (isTransacted == false) {
            String errorString = AdministeredObject.cr.getKString(ClientResources.X_NON_TRANSACTED);
            JMSException jmse = new javax.jms.IllegalStateException(errorString, ClientResources.X_NON_TRANSACTED);
            ExceptionHandler.throwJMSException(jmse);
        }

        if (failoverOccurred) {
            rollback();

            String errorString = AdministeredObject.cr.getKString(ClientResources.X_TRANSACTION_FAILOVER_OCCURRED);
            JMSException jmse = new TransactionRolledBackException(errorString, ClientResources.X_TRANSACTION_FAILOVER_OCCURRED);

            ExceptionHandler.throwJMSException(jmse);
        }

        // HACC -- this is due to ack failed or runtime exception in MDB.onMessage.
        // we prevent commit by throwing the exception here (bug 6667940).
        if (isRollbackOnly) {
            if (rollbackCause instanceof Exception) {
                ExceptionHandler.handleException((Exception) rollbackCause, ClientResources.X_CAUGHT_EXCEPTION);
            } else {
                Exception e = new Exception(rollbackCause);
                ExceptionHandler.handleException(e, ClientResources.X_CAUGHT_EXCEPTION);
            }
        }

        waitAllAsyncSendCompletion(null);

        JMSException rbrollbackex = null;
        boolean rbrollback = false;

        // set sync flag
        setInSyncState();

        try {
            // acknowledge the current message if in the reader thread.
            receiveCommit();
            // commit all messages sent and receive
            transaction.commit();
        } catch (JMSException jmse) {

            if (this.isRemoteException(jmse)) {

                // we are rolling back the transaction here.
                doRemoteFailedRollback(jmse);

            } else {

                if (!connection.isConnectedToHABroker()) { // 1-phase commit
                    if (jmse.getErrorCode().equals(ClientResources.X_SERVER_ERROR)) {
                        Exception e1 = jmse.getLinkedException();
                        if (e1 != null && (e1 instanceof JMSException) && (((JMSException) e1).getErrorCode().equals(Status.getString(Status.GONE))
                                || ((JMSException) e1).getErrorCode().equals(Status.getString(Status.CONFLICT)))) {
                            sessionLogger.log(Level.WARNING, "Exception on commit transaction " + transaction.getTransactionID() + ", will rollback", jmse);
                            rbrollbackex = jmse;
                            rbrollback = true;
                        }
                    }
                }

                if (!rbrollback) {
                    throw jmse;
                }

            }

        } finally {
            releaseInSyncState();
        }
        if (rbrollback) {
            JMSException ex = rbrollbackex;
            try {
                rollback();
                ex = new com.sun.messaging.jms.TransactionRolledBackException(rbrollbackex.getMessage(), rbrollbackex.getErrorCode());
            } catch (Exception e) {
                sessionLogger.log(Level.SEVERE, "Exception on rollback transaction " + transaction.getTransactionID() + " after commit failure", e);
                ex = rbrollbackex;
            }
            throw ex;
        }
    }

    protected void doRemoteFailedRollback(JMSException jmse) throws JMSException {

        // recreate consumers -- transaction is rolled back
        this.recreateConsumers();

        // construct the precise exception
        String errorString = AdministeredObject.cr.getKString(ClientResources.X_COMMIT_FAILED_REMOTE);

        JMSException newjmse = new com.sun.messaging.jms.TransactionRolledBackException(errorString, ClientResources.X_COMMIT_FAILED_REMOTE);

        // set exception link
        newjmse.setLinkedException(jmse);
        // throw the exception
        ExceptionHandler.throwJMSException(newjmse);
    }

    /**
     * Rollback any messages done in this transaction and releases any locks currently held.
     *
     * @exception JMSException if JMS implementation fails to rollback the the transaction due to some internal error.
     * @exception IllegalStateException if method is not called by a transacted session.
     *
     */

    public /* synchronized */ void rollback() throws JMSException {

        checkSessionState();
        checkPermissionForAsyncSend();

        if (isTransacted == false) {
            String errorString = AdministeredObject.cr.getKString(ClientResources.X_NON_TRANSACTED);
            JMSException jmse = new javax.jms.IllegalStateException(errorString, ClientResources.X_NON_TRANSACTED);
            ExceptionHandler.throwJMSException(jmse);
        }

        waitAllAsyncSendCompletion(null);

        // This will make sure that session is not closed/closing.
        setInSyncState();

        try {

            // check if we have a remote exception
            if (remore_broker_failed) {

                // delete and re-register consumers -- session is also rolled back.
                recreateConsumers();
                // reset the flag to false so that we can proceed
                remore_broker_failed = false;

                // we are done in rollback. messages not committed will be re-delivered.
                return;
            }

            // request
            // 1. all messages in the unAckedMessageQueue to be redelivered.
            // 2. all messages in the session queue and receive queues to be
            // redelivered.
            if (connection.isConnectedToHABroker) {
                rollbackHATransaction();
            } else {
                receiveRollback();
                // roll back all messages in the send queue.
                transaction.rollback();
            }

        } finally {

            // HACC -- reset flag (set when received exception from mdb/ack)
            this.isRollbackOnly = false;
            this.rollbackCause = null;

            // This will release sync state.
            failoverOccurred = false;

            releaseInSyncState();
        }
    }

    private void rollbackHATransaction() throws JMSException {

        try {
            receiveRollback();
            transaction.rollback();
        } catch (JMSException jmse) {
            String ecode = jmse.getErrorCode();
            if (ClientResources.X_NET_WRITE_PACKET.equals(ecode) || ClientResources.X_NET_ACK.equals(ecode)) {
                this.rollbackFailed(jmse);
            } else {
                throw jmse;
            }
        }
    }

    private void rollbackFailed(JMSException jmse) throws JMSException {

        if (connection.imqReconnect == false) {
            throw jmse;
        }

        // connection.checkAndSetReconnecting();
        yield();

        connection.checkReconnecting(null);

        if (connection.isCloseCalled || connection.connectionIsBroken) {
            throw jmse;
        }

        // receiveRollback();
        // transaction.rollback();

        // The transaction is rolled back by the broker. we only have to start
        // a new transaction.

        transaction.startNewLocalTransaction();
    }

    public static void yield() {

        try {
            Thread.yield();
            Thread.sleep(3000);
        } catch (Exception e) {
            
        }
    }

    /**
     * Close all consumers. Called from Session.close()
     *
     * @exception JMSException if close a consumer fails
     */
    // must be called from synchronized method
    private void closeConsumers() throws JMSException {
        /*
         * Enumeration e = consumers.elements(); MessageConsumerImpl consumer = null; while ( e.hasMoreElements() ) { consumer =
         * (MessageConsumerImpl) e.nextElement(); consumer.close(); }
         */

        Collection cons = consumers.values();
        MessageConsumerImpl[] consumerArray = (MessageConsumerImpl[]) cons.toArray(new MessageConsumerImpl[cons.size()]);

        for (int i = 0; i < consumerArray.length; i++) {
            consumerArray[i].close(true);
        }

        consumers.clear();
    }

    private void closeProducers() throws JMSException {
        MessageProducerImpl[] _producers = (MessageProducerImpl[]) producers.toArray(new MessageProducerImpl[producers.size()]);

        for (int i = 0; i < _producers.length; i++) {
            _producers[i].close();
        }

        producers.clear();
    }

    // must be called from synchronized method Session.close()
    private void closeBrowserConsumers() throws JMSException {
        // Enumeration e = browserConsumers.elements();
        // BrowserConsumer consumer = null;
        // while (e.hasMoreElements()) {
        // consumer = (BrowserConsumer)e.nextElement();
        // consumer.close();
        // }

        Collection bcons = browserConsumers.values();
        BrowserConsumer[] bcArray = (BrowserConsumer[]) bcons.toArray(new BrowserConsumer[bcons.size()]);
        for (int i = 0; i < bcArray.length; i++) {
            bcArray[i].close();
        }

        browserConsumers.clear();
    }

    /**
     * Since a provider may allocate some resources on behalf of a Session outside the JVM, clients should close them when
     * they are not needed. Relying on garbage collection to eventually reclaim these resources may not be timely enough.
     *
     * <P>
     * There is no need to close the producers and consumers of a closed session.
     *
     * <P>
     * This call will block until a receive or message listener in progress has completed. A blocked message consumer
     * receive call returns null when this session is closed.
     *
     * <P>
     * Closing a transacted session must rollback the in-progress transaction.
     *
     * <P>
     * This method is the only session method that can be concurrently called.
     *
     * <P>
     * Invoking any other session method on a closed session must throw JMSException.IllegalStateException. Closing a closed
     * session must NOT throw an exception.
     *
     * @exception JMSException if JMS implementation fails to close a Session due to some internal error.
     */
    public /* synchronized */ void close() throws JMSException {

        sessionLogger.log(Level.FINEST, "##### closing session.  consumer table size: " + consumers.values().size());
        // messages in the session queue.
        int reduceFlowCount = 0;

        // check if called from listener
        checkPermission();
        checkPermissionForAsyncSend();

        try {

            // This statement must be above synchronized block to avoid dead-lock
            // if calling Session.rollback concurrently. bug ID 6390095 and
            // 6390006
            prepareToClose(true);

            synchronized (sessionSyncObj) {
                try {

                    // closing a closed session, just return
                    if (isClosed) {
                        return;
                    }
                    // Wait for session to stop (this will block if another thread is in onMessage())
                    sessionQueue.stop(true);

                    // messages in the session queue
                    reduceFlowCount = sessionQueue.size();

                    // wait if commit/rollback/recover in process
                    // set inSyncState to true
                    // prepareToClose();

                    if (isTransacted) {
                        if (xaTxnMode) {

                            // **If we are in an xaTxn then we ack all received
                            // **messages.
                            // **The real commit happens only when the
                            // **XAResource.commit() is called by the TM

                            // ack all messages received in this session
                            // message has been acked already.
                            receiveCommit();
                            // All messages (recd & sent) [commit and rollback]
                            // will be handled by XAResource
                        } else {
                            if (connection.isBroken() == false && connection.recoverInProcess == false) {
                                transaction.releaseBrokerResource();
                            }
                        }
                    }

                    ////
                    // close all consumers
                    closeConsumers();
                    closeProducers();
                    closeBrowserConsumers();
                    sessionReader.close();

                    serverSessionRunner.serverSessionClose();

                } finally {
                    waitAllAsyncSendCompletion(null);
                    if (asyncSendCBProcessor != null) {
                        asyncSendCBProcessor.cancel();
                    }
                }

                connection.removeSession(this);
                connection.removeFromReadQTable(sessionId);

                // XXX PROTOCOL3.5
                if (connection.getBrokerProtocolLevel() >= PacketType.VERSION350) {
                    if (connection.isBroken() == false && connection.recoverInProcess == false) {
                        protocolHandler.deleteSession(this);
                    }
                }

                ////
                isClosed = true;
            }

        } finally {

            sessionLogger.log(Level.FINEST, "***** consumer table size: " + consumers.values().size());

            // unblock session queue
            if (isClosed == false) {
                this.sessionReader.close();
            }

            // unblock consumer queues
            if (consumers.values().size() > 0) {
                this.cleanUpConsumers();
            }

            /**
             * When closing session failed, we still want to mark this session as closed.
             */
            isClosed = true;

            serverSessionRunner.reset();
            if (connectionConsumer != null) {
                connectionConsumer.sessionClosed(this);
            }

            releaseInSyncState();
            // bug 6271876 -- connection flow control
            resetConnectionFlowControl(reduceFlowCount);

            if (sessionLogger.isLoggable(Level.FINE)) {
                logLifeCycle(ClientResources.I_SESSION_CLOSED);
            }
        }

        if (debug) {
            Debug.println("session closed ...");
            Debug.println(this);
        }
    }

    protected void cleanUpConsumers() {

        sessionLogger.log(Level.FINEST, "Cleaning up consumers in session.  SessionID: " + this.sessionId);

        Collection cons = consumers.values();
        MessageConsumerImpl[] consumerArray = (MessageConsumerImpl[]) cons.toArray(new MessageConsumerImpl[cons.size()]);

        for (int i = 0; i < consumerArray.length; i++) {
            consumerArray[i].receiveQueue.close();
            consumerArray[i].isClosed = true;
        }

        consumers.clear();
    }

    // bug 6271876 -- connection flow control
    protected void resetConnectionFlowControl(int reduceFlowCount) {

        if (connection.isCloseCalled) {
            return;
        }

        if (connection.protectMode && reduceFlowCount > 0) {
            readChannel.flowControl.resetFlowControl(connection, reduceFlowCount);
        }
    }

    /**
     * This method is provided for the MDB adaptor interface to close the session thread. The call is from session reader
     * thread, and no other consumers/producers in the session.
     */
    public void closeFromRA() {
        synchronized (raEndpointSyncObj) {
            sessionReader.close();
        }
    }

    /*
     * Set to true when this sesion is the one being used by an RA endpoint
     */
    public void _setRAEndpointSession() {
        // this field is never used.
        // raEndpointSession = true;
    }

    /*
     * start a local transaction called from RA when an mc is enlisted into a local txn rather than an xa txn
     */
    public void _startLocalTransaction() throws JMSException {
        if (isTransacted) {
            // ensure that transaction is non-null
            if (transaction == null) {
                throw new com.sun.messaging.jms.JMSException("MQRA:S:Can't start local transaction-transacted w/o Transaction Object");
            }
        } else {
            // ensure that transaction is null
            if (transaction != null) {
                throw new com.sun.messaging.jms.JMSException("MQRA:S:Can't start local transaction-already transacted");
            }
            transaction = new Transaction(this, true);
            isTransacted = true;
        }
    }

    /**
     * Called by close/stop methods to check if need to wait for message listener to complete.
     */
    protected boolean needToWait() {
        if (connection.isBroken()) {
            return false;
        } else {
            return true;
        }
    }

    /**
     * Stop message delivery in this session, and restart sending messages with the oldest unacknowledged message.
     *
     * <P>
     * All consumers deliver messages in a serial order. Acknowledging a received message automatically acknowledges all
     * messages that have been delivered to the client.
     *
     * <P>
     * Restarting a session causes it to take the following actions:
     *
     * <UL>
     * <LI>Stop message delivery
     * <LI>Mark all messages that might have been delivered but not acknowledged as `redelivered'
     * <LI>Restart the delivery sequence including all unacknowledged messages that had been previously delivered.
     *
     * <P>
     * Redelivered messages do not have to be delivered in exactly their original delivery order.
     * </UL>
     *
     * @exception JMSException if JMS implementation fails to stop message delivery and restart message send due to due to
     * some internal error.
     * @exception IllegalStateException if method is called by a transacted session.
     */

    public void recover() throws JMSException {
        // boolean decremented = false;

        // Throw exception if closed
        checkSessionState();

        // transacted session is not allowed to call this method.
        if (isTransacted) {
            String errorString = AdministeredObject.cr.getKString(ClientResources.X_TRANSACTED);
            JMSException jmse = new javax.jms.IllegalStateException(errorString, ClientResources.X_TRANSACTED);

            ExceptionHandler.throwJMSException(jmse);
        }

        // NO_ACKNOWLEDGE mode does now allow to call this method.
        if (acknowledgeMode == com.sun.messaging.jms.Session.NO_ACKNOWLEDGE) {
            String errorString = AdministeredObject.cr.getKString(ClientResources.X_NO_ACKNOWLEDGE_RECOVER);
            JMSException jmse = new javax.jms.IllegalStateException(errorString, ClientResources.X_NO_ACKNOWLEDGE_RECOVER);

            ExceptionHandler.throwJMSException(jmse);
        }

        // check if we have a remote exception
        if (remore_broker_failed) {
            // delete and re-register consumers
            recreateConsumers();
            // reset the flag to false so that we can proceed
            remore_broker_failed = false;

            // we are done in recover. messages not ack successfully will be re-delivered.
            return;
        }

        // no-op for non client acked session
        // bug ID 4678413 -- We now allow all ack mode to call Session.recover().
        /*
         * if ( acknowledgeMode != Session.CLIENT_ACKNOWLEDGE ) { return; }
         */

        setInSyncState();

        try {
            switch (acknowledgeMode) {
            case Session.AUTO_ACKNOWLEDGE:
                /**
                 * We want to make sure that for these conditions the message does not want to be acked.
                 */
                if (Thread.currentThread() == sessionReader.sessionThread) {
                    sessionReader.currentMessage.doAcknowledge = false;
                } else if (Thread.currentThread() == serverSessionRunner.getCurrentThread()) {
                    serverSessionRunner.currentMessage.doAcknowledge = false;
                }
                // NOTE: fall through here.
            case Session.CLIENT_ACKNOWLEDGE:
            case Session.DUPS_OK_ACKNOWLEDGE:

                // include the current message to recover if called from message listener
                if (Thread.currentThread() == sessionReader.sessionThread) {
                    prepareClientAcknowledge(sessionReader.currentMessage);
                } else if (Thread.currentThread() == serverSessionRunner.getCurrentThread()) {
                    prepareClientAcknowledge(serverSessionRunner.currentMessage);
                }
                break;
            }

        } catch (Exception e1) {
        }

        try {
            // stop message delivery from broker
            stopSession();

            /*
             * Because the caller is the session controlling thread, we do not have to call stop/start methods. We know that no
             * messages are delivering to the consumers at this moment.
             */
            // GT Have to stop *unless* it is the session thread
            // otherwise the redeliver lists will be wrong
            if ((Thread.currentThread() != sessionReader.sessionThread) && (Thread.currentThread() != serverSessionRunner.getCurrentThread())) {
                stop();
            }
            // request redeliver of unacked messages - set redelivered flag to true
            // GT reorder the REDELIVER protocol msgs to ensure correct order for redelivery
            // redeliverUnAckedMessages(true);
            redeliverMessagesInQueues(false);
            // request redeliver of messages in different queues but not delivered
            // to the client yet - set redelivered flag to false
            // GT reorder as explained above
            // redeliverMessagesInQueues (false);
            redeliverUnAckedMessages(true);

            failoverOccurred = false;

            // GT Have to start *unless* it is the session thread
            if ((Thread.currentThread() != sessionReader.sessionThread) && (Thread.currentThread() != serverSessionRunner.getCurrentThread())) {
                start();
            }
        } finally {

            // start message delivery
            releaseInSyncState();
            resumeSession();

        }
    }

    /**
     * Tell the broker to stop sending messages for this session.
     *
     * The 3.0.x brokers don't know about sessions. So in that case we just stop the entire connection.
     */
    protected void stopSession() throws JMSException {
        if (connection.getBrokerProtocolLevel() < PacketType.VERSION350) {
            protocolHandler.incStoppedCount();
            protocolHandler.stop();
        } else {
            protocolHandler.stopSession(brokerSessionID);
        }
    }

    /**
     * Tell the broker to resume message delivery for this session.
     *
     * The 3.0.x brokers don't know about sessions. So in that case we just start the connection.
     */
    protected void resumeSession() throws JMSException {
        if (connection.getBrokerProtocolLevel() < PacketType.VERSION350) {
            protocolHandler.decStoppedCount();
            // GT XXX timing hole - fix after FCS

            // SB XXX There is no known test case for this timing
            // hole. It is theoretically possible that if a thread
            // calls connection.stop while another thread is doing
            // session.recover or rollback, there may be some
            // problems. Since raptor is capable of explicitly
            // stopping a session (during rollback / recover) this is
            // not an issue starting from 3.5 release...

            if (!connection.getIsStopped()) {
                protocolHandler.start();
            }
        } else {
            protocolHandler.resumeSession(brokerSessionID);
        }
    }

    /**
     * Called before commit/rollback/recover ...
     */
    protected void setInSyncState() throws JMSException {
        synchronized (syncObject) {

            checkSessionState();

            if (inSyncState) {

                // Some other thread is performing critical operation on this session
                // which is illegal unless this thread is the MessageListener thread,
                // and the other thread is calling Session.close() or Consumer.close
                if (isIsMessageListenerThread()
                        && (inSyncStateOperation == INSYNCSTATE_SESSION_CLOSING || inSyncStateOperation == INSYNCSTATE_CONSUMER_CLOSING)) {
                    // this is an onMessage() thread
                    // allow the close to continue in the other thread (it should be blocking until onMessage() returns)
                    // and carry on in this thread
                    return;
                }

                if (inSyncStateOperation == INSYNCSTATE_CONSUMER_CLOSING) {
                    long totalwaited = 0L;
                    long waittime = waitTimeoutForConsumerCloseDone;
                    while (inSyncState && inSyncStateOperation == INSYNCSTATE_CONSUMER_CLOSING && (waittime > 0L || waitTimeoutForConsumerCloseDone == 0L)) {
                        checkSessionState();
                        long starttime = System.currentTimeMillis();
                        try {
                            syncObject.wait(waittime);
                        } catch (InterruptedException e) {
                            Debug.printStackTrace(e);
                        }
                        totalwaited += (System.currentTimeMillis() - starttime);
                        waittime = waitTimeoutForConsumerCloseDone - totalwaited;
                        if (waittime < 0L) {
                            waittime = 0L;
                        }
                    }
                    if (!inSyncState) {
                        inSyncState = true;
                        inSyncStateOperation = INSYNCSTATE_OTHER;
                        return;
                    }
                }

                String errorString = AdministeredObject.cr.getKString(ClientResources.X_CONFLICT);
                JMSException jmse = new javax.jms.IllegalStateException(errorString, ClientResources.X_CONFLICT);

                ExceptionHandler.throwJMSException(jmse);
            }

            inSyncState = true;
            inSyncStateOperation = INSYNCSTATE_OTHER;
        }
    }

    /**
     * Called after commit/rollback/recover
     */
    protected void releaseInSyncState() {
        synchronized (syncObject) {
            inSyncState = false;
            // unset the reason why we're in inSyncState
            inSyncStateOperation = INSYNCSTATE_NOTSET;

            syncObject.notifyAll();
        }
    }

    /**
     * Get inSync status.
     */
    protected boolean getInSyncState() {
        return inSyncState;
    }

    /**
     * This method set the inSyncState flag to true. It waits until commit/rollback/recover returns.
     *
     * <p>
     * Commit/rollback/recover throws JMSException if they are called after close is called.
     */
    protected void prepareToClose(boolean fromSessionClose) {

        synchronized (syncObject) {
            // if inSync state, wait until done
            while (inSyncState) {
                try {
                    syncObject.wait();
                } catch (InterruptedException e) {
                    Debug.printStackTrace(e);
                }
            }

            // set to true so that commit/rollback/recover
            // will throw exception ...
            inSyncState = true;

            // record why we've set inSyncState
            if (fromSessionClose) {
                inSyncStateOperation = INSYNCSTATE_SESSION_CLOSING;
            } else {
                inSyncStateOperation = INSYNCSTATE_CONSUMER_CLOSING;
            }
        }
    }

    /**
     * For transacted session, acknowledge all unacked messages. If Session.commit() is called from MessageListener, the
     * current message is not acknowledged.
     *
     * NOTE: The implementation has been changed. The new implementation only need to acknowledge the current message if
     * commit() is called from the reader thread.
     */
    protected void receiveCommit() throws JMSException {
        // include the current message to recover if called from message listener

        if (Thread.currentThread() == sessionReader.sessionThread) {
            transactedAcknowledge(sessionReader.currentMessage);
        } else if (Thread.currentThread() == serverSessionRunner.getCurrentThread()) {
            transactedAcknowledge(serverSessionRunner.currentMessage);
        }

        // clean up unacked Q
        // bug 6423696 - Session.rollback does not actually ...
        // The fix is to clear the unAckedMessageQueue only after
        // commit has successfully returned.
        // The action to clear the Q is moved to Transaction.java
        // unAckedMessageQueue.clear();

        /*
         * if ( Thread.currentThread() == sessionReader.sessionThread ) { prepareTransactedAcknowledge
         * (sessionReader.currentMessage); } else if (Thread.currentThread() == serverSessionRunner.getCurrentThread()) {
         * prepareTransactedAcknowledge (serverSessionRunner.currentMessage); } //only need to send ack if there are messages in
         * the un acked queue. if ( unAckedMessageQueue.size() > 0 ) { dequeue ( unAckedMessageQueue ); //set transaction ID
         * ackPkt.setTransactionID( transaction.getTransactionID() ); //do acknowledge, require broker to ack back.
         * doAcknowledge(true); }
         */
    }

    /**
     * This method is called after ProtocolHandler.commit() return a OK status.
     *
     */
    protected void clearUnackedMessageQ() {
        this.unAckedMessageQueue.clear();
    }

    /**
     * Called by rollback() in a transacted session. This method handles rollback for consuming messages
     *
     * <p>
     * All messages in the unAckedMessageQueue, receive queues, and session queue will be redelivered.
     */
    protected void receiveRollback() throws JMSException {
        // XXX REVISIT chiaming: NO transaction ID involved???

        // include the current message to recover if called from message listener
        if (Thread.currentThread() == sessionReader.sessionThread) {
            prepareTransactedAcknowledge(sessionReader.currentMessage);
        } else if (Thread.currentThread() == serverSessionRunner.getCurrentThread()) {
            prepareTransactedAcknowledge(serverSessionRunner.currentMessage);
        }

        // stop message delivery from broker
        stopSession();

        // stop this session, all message delivery in the session is stopped.
        // DO NOT need to stop this session because this is the controlling
        // thread calling this method.
        // GT Have to stop *unless* it is the session thread
        // otherwise the redeliver lists will be wrong
        if ((Thread.currentThread() != sessionReader.sessionThread) && (Thread.currentThread() != serverSessionRunner.getCurrentThread())) {
            stop();
        }

        // put MID from unacked message queue to dos
        // dequeueUnAckedMessages();

        // put MID from all consumer queues and session queue to dos
        // dequeueMessagesInQueues();

        // for bug id 5018703 - we must send two separate pkt with
        // the right redeliver flag. This is similar to recover().
        this.redeliverMessagesInQueues(false);
        this.redeliverUnAckedMessages(true);

        // redeliver and set redeliver flag to true
        // redeliver (true);

        // start current session again
        // GT Have to start *unless* it is the session thread
        if ((Thread.currentThread() != sessionReader.sessionThread) && (Thread.currentThread() != serverSessionRunner.getCurrentThread())) {
            start();
        }
        // start message delivery
        resumeSession();
    }

    /**
     * Caller must in setInSyncState block
     *
     * This method is used to rollback a transaction that failed to commit and broker indicates client runtime should
     * rollback it
     */
    protected void rollbackAfterReceiveCommit(JMQXid jmqXid) throws JMSException {

        checkSessionState();

        // stop message delivery from broker
        stopSession();
        boolean stoppedbyme = false;
        try {

            // Have to stop *unless* it is the session thread
            // otherwise the redeliver lists will be wrong
            if ((Thread.currentThread() != sessionReader.sessionThread) && (Thread.currentThread() != serverSessionRunner.getCurrentThread())) {
                stop();
                stoppedbyme = true;
            }
            this.redeliverMessagesInQueues(false);

            if ((Thread.currentThread() != sessionReader.sessionThread) && (Thread.currentThread() != serverSessionRunner.getCurrentThread())) {
                start();
                stoppedbyme = false;
            }

            connection.getProtocolHandler().rollback(0L, jmqXid, true);
        } finally {
            try {
                if (stoppedbyme) {
                    start();
                }
            } finally {
                resumeSession();
            }
        }
    }

    /**
     * Called by recover(). Redeliver messages in the unacked message queue.
     *
     * @param redeliverFlag the falg that broker will set to the messages when redeliver.
     */
    protected void redeliverUnAckedMessages(boolean redeliverFlag) throws JMSException {
        dequeueUnAckedMessages();
        // commit redeliver
        redeliver(redeliverFlag);
    }

    /**
     * Redeliver messages in the consumer's receive queues and session queue
     */
    protected void redeliverMessagesInQueues(boolean redeliverFlag) throws JMSException {
        dequeueMessagesInQueues();
        // commit redeliver
        redeliver(redeliverFlag);
    }

    /**
     * Dequeue unacked messages from unAckedMessageQueue and write the message IDs to the data output stream.
     *
     * <p>
     * Reset the ack counter to 0 since the queue is empty.
     */
    // protected void dequeueUnAckedMessages() throws JMSException {
    // dequeue unacked message queue
    // dequeue (unAckedMessageQueue);
    // reset ack counter
    // ackCounter = 0;
    // }

    /**
     * Loop through each MessageConsumer and dequeue its receiveQueue in this session. Message Ids are written to the data
     * output stream.
     *
     * <p>
     * Dequeue the SessionQueue after the above action.
     */
    protected void dequeueMessagesInQueues() throws JMSException {
        MessageConsumerImpl consumer = null;
        Enumeration enum2 = consumers.elements();

        int reduceFlowCount = 0;

        while (enum2.hasMoreElements()) {
            consumer = (MessageConsumerImpl) enum2.nextElement();

            // add messages in the consumer receive queue
            reduceFlowCount = reduceFlowCount + consumer.receiveQueue.size();

            // dequeue receive queue for each consumer in this session
            dequeueReceiveQ(consumer.receiveQueue);

            // XXX PROTOCOL 3.5
            // Reset the flow control counters for all the consumers
            // for this session.
            readChannel.flowControl.resetFlowControl(consumer, 0);

        }

        // add messages in the session queue
        reduceFlowCount = reduceFlowCount + sessionQueue.size();

        // dequeue the currect session's session queue
        dequeueSessionQ(sessionQueue);

        // bug 6271876 -- connection flow control
        resetConnectionFlowControl(reduceFlowCount);

        // XXX REVISIT "dequeue" from serverSessionMessageQ ?
    }

    /**
     * Loop through each element and write MID to dos. elements are deleted after used.
     *
     * @param queue the SessionQueue to be dequeued
     */
    protected void dequeueReceiveQ(ReceiveQueue queue) throws JMSException {
        MessageImpl message = null;
        // GT
        // System.out.println(">>>dequeing..ReceiveQ dump");
        while (queue.isEmpty() == false) {
            if ((message = (MessageImpl) queue.dequeue()) != null) {
                writeMessageID(message);
                // GT
                // message.dump(System.out);
            }
        }
        // GT
        // System.out.println(">>>dequeing..ReceiveQ dump done");
        // System.out.println(">>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>");
    }

    protected void dequeueSessionQ(SessionQueue queue) throws JMSException {
        ReadOnlyPacket pkt = null;
        // GT
        // System.out.println(">>>dequeing..SessionQ dump");
        while (queue.isEmpty() == false) {
            if ((pkt = (ReadOnlyPacket) queue.dequeue()) != null) {
                writeMessageID(pkt);
                // GT
                // pkt.dump(System.out);
            }
        }
        // GT
        // System.out.println(">>>dequeing..SessionQ dump done");
        // System.out.println(">>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>");
    }

    /**
     * Loop through each element and write MID to dos. elements are deleted after used.
     *
     * @param queue the Vector to be dequeued
     */
    private void dequeueUnAckedMessages() throws JMSException {
        // bug 4934856
        UnAckedMessage unAckedMessage = null;
        int size = unAckedMessageQueue.size();

        // GT
        // System.out.println(">>>dequeing..dequeue dump");
        for (int i = 0; i < size; i++) {
            unAckedMessage = (UnAckedMessage) unAckedMessageQueue.elementAt(i);
            writeMessageID(unAckedMessage);
            // GT
            // unAckedMessage.dump(System.out);
        }
        // GT
        // System.out.println(">>>dequeing..dequeue dump done");

        unAckedMessageQueue.removeAllElements();

        this.ackCounter = 0;
    }

    /**
     * public void _redeliverMessageFromRA(MessageImpl message) throws JMSException { synchronized (raEndpointSyncObj) {
     *
     * if (message != null) { writeMessageID(message);
     *
     * ReadWritePacket pkt = new ReadWritePacket(); try { dos.flush(); bos.flush();
     *
     * //set message body pkt.setMessageBody(bos.toByteArray());
     *
     * //for transacted session, set transaction ID to pkt ////if ( isTransacted ) { ////pkt.setTransactionID(
     * transaction.getTransactionID() ); ////}
     *
     * //write packet - ensure that this message is marked 'redelivered' protocolHandler.redeliver (pkt, true,
     * isTransacted); //reset buf count to 0 bos.reset();
     *
     * } catch (IOException e) { ExceptionHandler.handleException(e, ClientResources.X_MESSAGE_REDELIVER); } } } }
     **/

    /**
     * Redeliver all messages in the current DataOutputStream.
     *
     * @param redeliverFlag the flag for broker to set for redelivered messages.
     */
    protected void redeliver(boolean redeliverFlag) throws JMSException {

        // do not request redeliver if received no messages
        if (bos.size() == 0) {
            return;
        }

        ReadWritePacket pkt = new ReadWritePacket();
        try {
            dos.flush();
            bos.flush();
            // set message body
            pkt.setMessageBody(bos.toByteArray());

            // for transacted session, set transaction ID to pkt
            if (isTransacted) {
                pkt.setTransactionID(transaction.getTransactionID());
            }

            // write packet
            protocolHandler.redeliver(pkt, redeliverFlag, isTransacted);
            // reset buf count to 0
            bos.reset();

        } catch (IOException e) {
            ExceptionHandler.handleException(e, ClientResources.X_MESSAGE_REDELIVER);
        }
    }

    /**
     * Return the session's distinguished message listener (optional).
     *
     * @return the message listener associated with this session.
     *
     * @exception JMSException if JMS fails to get the message listener due to an internal error in JMS Provider.
     *
     * @see javax.jms.Session#setMessageListener
     * @see javax.jms.ServerSessionPool
     * @see javax.jms.ServerSession
     */

    public MessageListener getMessageListener() throws JMSException {
        checkSessionState();
        return serverSessionRunner.getMessageListener();
    }

    /**
     * Set the session's distinguished message listener (optional). When it is set no other form of message receipt in the
     * session can be used; however, all forms of sending messages are still supported. This is an expert facility not used
     * by regular JMS clients.
     *
     * @param listener the message listener to associate with this session.
     *
     * @exception JMSException if JMS fails to set the message listener due to an internal error in JMS Provider.
     *
     * @see javax.jms.Session#getMessageListener
     * @see javax.jms.ServerSessionPool
     * @see javax.jms.ServerSession
     */

    public /* synchronized */ void setMessageListener(MessageListener listener) throws JMSException {

        checkSessionState();

        if (listener != null && consumers.size() > 0) {
            String errorString = AdministeredObject.cr.getKString(ClientResources.X_SVRSESSION_MESSAGECONSUMER);
            JMSException jmse = new javax.jms.IllegalStateException(errorString, ClientResources.X_SVRSESSION_MESSAGECONSUMER);

            ExceptionHandler.throwJMSException(jmse);
        }
        serverSessionRunner.setMessageListener(listener);
    }

    /**
     * Only intended to be used by Application Servers (optional operation).
     *
     * @see javax.jms.ServerSession
     */
    public void run() {
        serverSessionRunner.run();
    }

    protected void loadMessageToServerSession(MessageImpl message, ServerSession ss, boolean isDMQMessage) {
        serverSessionRunner.loadMessage(message, ss, isDMQMessage);
    }

    protected SessionQueue getSessionQueue() {
        return sessionQueue;
    }

    /**
     * Non-public API. This method should be called right after ack is returned.
     *
     * @return ack flag for acknowledgement. If true, ack waits for broker's acknowledgement. Otherwise, acknowledge returns
     * without waiting for broker's acknowledgement.
     */
    public boolean _getAckSendAcknowledge() {
        return ackPkt.getSendAcknowledge();
    }

    /**
     * Get acknowledge mode
     */
    public int _getAcknowledgeMode() {
        return acknowledgeMode;
    }

    protected boolean _getXaTxnMode() {
        return xaTxnMode;
    }

    protected void _setXaTxnMode(boolean mode) {
        xaTxnMode = mode;
    }

    public long getBrokerSessionID() {
        return brokerSessionID;
    }

    public void setBrokerSessionID(long brokerSessionID) {
        this.brokerSessionID = brokerSessionID;
    }

    public Transaction _getTransaction() {
        return transaction;
    }

    @Override
    public void setFailoverOccurred(boolean v) {
        failoverOccurred = v;
    }

    @Override
    public void initXATransactionForMC(long transactionID) throws JMSException {
        if (transaction == null) {
            transaction = new Transaction(this, false);
        }
        transaction.setTransactionID(transactionID);
        xaTxnMode = true;
        isTransacted = true;
    }

    @Override
    public void finishXATransactionForMC() {
        // No longer needs to be in a dist txn
        xaTxnMode = false;
        // Done with Transaction delegate!
        isTransacted = false;
        transaction = null;
    }

    @Override
    public void dump(PrintStream ps) {

        ps.println("------ SessionImpl dump ------");
        ps.println("broker session ID: " + brokerSessionID);
        ps.println("session ID: " + sessionId);

        // dump session reader status
        if (sessionReader != null) {
            sessionReader.dump(ps);
        }
        // dump session queue status
        if (sessionQueue != null) {
            sessionQueue.dump(ps);
        }
        // dump unAckedMessageQueue
        if (unAckedMessageQueue != null) {
            ps.println("Number of Unacked messages: " + unAckedMessageQueue.size());
        }

        ps.println("# of message consumers: " + consumers.size());
        // dump message consumers status
        Enumeration enum2 = consumers.elements();
        while (enum2.hasMoreElements()) {
            MessageConsumerImpl consumer = (MessageConsumerImpl) enum2.nextElement();
            consumer.dump(ps);
        }

        serverSessionRunner.dump(ps);
    }

    protected Hashtable getDebugState(boolean verbose) {
        Hashtable ht = new Hashtable();

        ht.put("sessionId", String.valueOf(sessionId));
        ht.put("brokerSessionID", String.valueOf(brokerSessionID));
        ht.put("isTransacted", String.valueOf(isTransacted));
        ht.put("ackMode", String.valueOf(acknowledgeMode));
        ht.put("dupsOkLimit", String.valueOf(dupsOkLimit));
        ht.put("isAckLimited", String.valueOf(isAckLimited));
        ht.put("ackLimit", String.valueOf(ackLimit));
        ht.put("ackCounter", String.valueOf(ackCounter));
        ht.put("xaTxnMode", String.valueOf(xaTxnMode));
        ht.put("rxCount", String.valueOf(TEST_rxCount));
        ht.put("ackCount", String.valueOf(TEST_ackCount));
        ht.put("isStopped", String.valueOf(isStopped));

        ht.put("# Consumers", String.valueOf(consumers.size()));
        int n = 0;
        Enumeration enum2 = consumers.elements();
        while (enum2.hasMoreElements()) {
            MessageConsumerImpl consumer = (MessageConsumerImpl) enum2.nextElement();
            ht.put("Consumer[" + n + "]", consumer.getDebugState(verbose));
            n++;
        }

        ht.put("# Producers", String.valueOf(producers.size()));
        MessageProducerImpl[] _producers = (MessageProducerImpl[]) producers.toArray(new MessageProducerImpl[producers.size()]);
        for (int i = 0; i < _producers.length; i++) {
            ht.put("Producer[" + i + "]", _producers[i].getDebugState(verbose));
        }
        ht.put("unAckedMessageQueueSize", unAckedMessageQueue.size());
        if (verbose) {
            ht.put("unAckedMessageQueue", unAckedMessageQueue);
        }
        SessionQueue ssq = sessionQueue;
        if (ssq != null) {
            ht.put("sessionQueue", ssq.getDebugState(verbose));
        }
        ConnectionConsumerImpl cc = connectionConsumer;
        if (cc != null) {
            ht.put("connectionConsumer", cc.getDebugState(verbose));
        }
        ServerSessionRunner ssr = serverSessionRunner;
        if (ssr != null) {
            ht.put("serverSessionRunner", ssr.getDebugState(verbose));
        }

        return ht;
    }

    /**
     * backward compatibility -- 4934856
     *
     * @param message the message used to call client ack method.
     * @throws JMSException
     */
    private void checkClientAckMessage(MessageImpl message) throws JMSException {

        if (connection.getBrokerProtocolLevel() < com.sun.messaging.jmq.io.PacketType.VERSION350) {

            Long id = Long.valueOf(message.getInterestID());

            if (consumers.containsKey(id) == false) {
                // "Cannot acknowledge message for closed consumer"
                String errorString = AdministeredObject.cr.getKString(ClientResources.X_CLIENT_ACKNOWLEDGE);
                JMSException jmse = new javax.jms.IllegalStateException(errorString, ClientResources.X_CLIENT_ACKNOWLEDGE);

                ExceptionHandler.throwJMSException(jmse);
            }
        }
    }

    /**
     * When message consumer is closed, we need to remove unacked messages for transacted/clientAck session. -- 4934856
     */
    protected void removeUnAckedMessages(Long interestId) throws JMSException {
        int size = unAckedMessageQueue.size();
        if (size > 0) { // there are messages in the unacked q.

            Vector removeq = new Vector();
            // interest id for this consumer
            // XXX PROTOCOL2.1
            long consumerID = interestId.longValue();

            // find unacked messages for this consumer and put
            // them in the removeq
            // this is not synchronized because no other thread is
            // modifying the unackq.
            for (int i = 0; i < size; i++) {
                UnAckedMessage msg = (UnAckedMessage) (unAckedMessageQueue.elementAt(i));
                if (msg.getConsumerID() == consumerID) {
                    // This message can not be used to do acknowledge
                    // for client ack mode.
                    // msg.doAcknowledge = false;
                    removeq.addElement(msg);
                }
            }

            // remove messages in the rollback queue
            for (int i = 0; i < removeq.size(); i++) {
                // System.out.println("********* removing msg from unackq: "+ i);
                if (debug) {
                    Debug.println("removing msg from unackq: " + removeq.elementAt(i));
                }
                removeMessageFromAckList((UnAckedMessage) removeq.elementAt(i));
            }
        }
    }

    public void logLifeCycle(String key) {

        if (sessionLogger.isLoggable(Level.FINE)) {
            sessionLogger.log(Level.FINE, key, this);
        }
    }

    @Override
    public String toString() {
        return "ConnectionID=" + this.connection.getConnectionID() + ", SessionID=" + this.brokerSessionID;
    }

    /**
     * Light weight class to hold Unacked message data. This is used to recover or rollback messages.
     */
    private static class UnAckedMessage {

        private SysMessageID mid = null;
        private long cid = -1;

        private UnAckedMessage(MessageImpl message) {
            this.mid = message.getMessageID();
            this.cid = message.getInterestID();
        }

        public SysMessageID getMessageID() {
            return mid;
        }

        public long getConsumerID() {
            return cid;
        }

        @Override
        public String toString() {
            return "mid:[" + ((mid != null) ? mid.toString() : "") + "] cid:" + cid;
        }
    }

    /**
     * The method is called when client runtime detects that the remote broker had failed and any of the following
     * conditions is true.
     *
     * 1. if ((ack_mode == transacted) and (Session.commit())) is called.
     *
     * Broker sets status code (in commit_reply/prepare_reply) to inform client runtime that recreate consumer is required.
     *
     * 1.1 Client runtime calls this method to delete and add consumers in the session. 1.2 The transaction is rolled back.
     * A transaction rolled back exception is thrown. A new transaction is created.
     *
     * 2. if ((ack_mode == transacted) and (Session.rollback())) is called.
     *
     * If the client runtime has a state indicating that the remote broker had failed:
     *
     * 2.1 Client runtime calls this method to delete and add consumers in the session. 2.2 The transaction is rolled back.
     * A new transaction is created.
     *
     * 3. if ((ack_mode == client_ack) and (Session.recover())) is called.
     *
     * If the client runtime has a state indicating that the remote broker had failed:
     *
     * 3.1 Client runtime calls this method to delete and add consumers in the session. 3.2 The session is recovered.
     * Messages ack failed will be redelivered.
     *
     * 4. If ((ack_mode == auto_ack) || (ack_mode == dups_ok_ack))
     *
     * If the client runtime has a state indicating that the remote broker had failed:
     *
     * 4.1 Client runtime calls this method to delete and add consumers in the session. 4.2 Messages not acknowledged
     * (includes ack failed) are redelivered.
     */
    protected void recreateConsumers() throws JMSException {
        recreateConsumers(false);
    }

    protected void recreateConsumers(boolean fromXAResourceImpl) throws JMSException {

        try {

            sessionLogger.finest("Re-creating consumers for the session: " + this.sessionId);

            // the current consumers in the session is saved to recreate after delete them.
            Object savedConsumers[] = consumers.values().toArray();

            // 1. stop message delivery for the session.
            // this is the active session thread to reconstruct the state of the consumers.
            stopSession();

            // 2. stop session reader thread.
            if ((Thread.currentThread() != sessionReader.sessionThread) && (Thread.currentThread() != serverSessionRunner.getCurrentThread())) {
                // we must not wait for app thread to be locked. We simply block (mark a flag in
                // delivery Qs only) all message delivery.
                stop(false);
            }

            // 3. clean up messages in session queue
            sessionQueue.clear();

            // 4. Clear Consumer queue, remove interest
            for (int i = 0; i < savedConsumers.length; i++) {
                // clear consumer queue.
                ((MessageConsumerImpl) savedConsumers[i]).receiveQueue.clear();

                // remove interest to broker
                ((MessageConsumerImpl) savedConsumers[i]).deregisterInterest();

                // log
                ((MessageConsumerImpl) savedConsumers[i]).logLifeCycle(ClientResources.I_CONSUMER_CLOSED);
            }

            // 4. Clear unacked message queue
            if (unAckedMessageQueue != null) {
                unAckedMessageQueue.removeAllElements();
            }

            // 5. clean up the consumers table in the session
            consumers.clear();

            // 6. send roll back packet if transacted session
            if (!fromXAResourceImpl && this.isTransacted) {
                transaction.rollback();
            }

            // 7. recreate consumers.
            for (int i = 0; i < savedConsumers.length; i++) {

                ((MessageConsumerImpl) savedConsumers[i]).registerInterest();

                ((MessageConsumerImpl) savedConsumers[i]).logLifeCycle(ClientResources.I_CONSUMER_CREATED);
            }

            // 8. resume session
            resumeSession();

            // 9. restart session thread if stopped
            if ((Thread.currentThread() != sessionReader.sessionThread) && (Thread.currentThread() != serverSessionRunner.getCurrentThread())) {
                start();
            }

            // 10. reset falg
            remore_broker_failed = false;

            sessionLogger.finest("Consumers recreated for the session: " + this.sessionId);

        } catch (JMSException jmse) {
            sessionLogger.log(Level.SEVERE, jmse.getMessage(), jmse);
            throw jmse;
        } finally {
            // do nothing now.
        }
    }

    public boolean _appCheckRemoteException(JMSException jmse) {
        if (jmse instanceof RemoteAcknowledgeException) {
            return isRemoteException(jmse);
        }
        Exception e = jmse.getLinkedException();
        if (e == null || !(e instanceof RemoteAcknowledgeException)) {
            return false;
        }
        return isRemoteException((JMSException) e);
    }

    /**
     * Check if this is a remote ack/commit failed exception
     *
     * Re-create consumers in the session if it is caused by remore broker failure.
     *
     * @param jmse
     */
    protected boolean isRemoteException(JMSException jmse) {
        boolean isRemoteFailed = false;
        String errcode = jmse.getErrorCode();

        if (ClientResources.X_ACK_FAILED_REMOTE.equals(errcode) || ClientResources.X_AUTO_ACK_FAILED_REMOTE.equals(errcode)
                || ClientResources.X_CLIENT_ACK_FAILED_REMOTE.equals(errcode) || ClientResources.X_COMMIT_FAILED_REMOTE.equals(errcode)) {

            if (this.matchConsumerIDs((RemoteAcknowledgeException) jmse, consumers, sessionLogger)) {
                isRemoteFailed = true;
            }
        }
        return isRemoteFailed;
    }

    /**
     * Match the consumer IDs contained in the specified RemoteAcknowledgeException with the consumer IDs in the session
     * consumers table.
     *
     * @param rae
     * @return true if the consumers table contains a consumer with cid in the
     * RemoteAcknowledgeException.JMQRemoteConsumerIDs property.
     */
    protected static boolean matchConsumerIDs(RemoteAcknowledgeException rae, Hashtable cons, Logger logger) {

        Hashtable prop = rae.getProperties();
        if (prop == null) {
            return false;
        }
        String cvalue = (String) prop.get(RemoteAcknowledgeException.JMQRemoteConsumerIDs);
        if (cvalue == null) {
            return false;
        }

        StringTokenizer st = new StringTokenizer(cvalue);

        while (st.hasMoreTokens()) {
            String cidstr = st.nextToken();
            Long cid = new Long(cidstr);
            Object obj = cons.get(cid);
            if (obj != null) {
                logger.finest("SessionImpl.matchConsumerIDs: Consumer ID matches: " + cidstr);
                return true;
            }
        }
        return false;
    }

    public void setIsMessageListenerThread(boolean bool) {
        isMessageListener.set(Boolean.valueOf(bool));
    }

    public boolean isIsMessageListenerThread() {
        Boolean value = isMessageListener.get();
        if (value == null) {
            return false;
        } else {
            return value.booleanValue();
        }
    }

}
