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Posted to commits@activemq.apache.org by gt...@apache.org on 2014/10/17 17:55:40 UTC
git commit: https://issues.apache.org/jira/browse/AMQ-5266
https://issues.apache.org/jira/browse/AMQ-4485 - fix warn logging from kahadb
on set batch when message already consumed using seq from messageId,
additional single dest test that hammers this ca
Repository: activemq
Updated Branches:
refs/heads/trunk 28b45341d -> 1d39f08c1
https://issues.apache.org/jira/browse/AMQ-5266 https://issues.apache.org/jira/browse/AMQ-4485 - fix warn logging from kahadb on set batch when message already consumed using seq from messageId, additional single dest test that hammers this case
Project: http://git-wip-us.apache.org/repos/asf/activemq/repo
Commit: http://git-wip-us.apache.org/repos/asf/activemq/commit/1d39f08c
Tree: http://git-wip-us.apache.org/repos/asf/activemq/tree/1d39f08c
Diff: http://git-wip-us.apache.org/repos/asf/activemq/diff/1d39f08c
Branch: refs/heads/trunk
Commit: 1d39f08c12de9590e31006fae421abb1ee2cca90
Parents: 28b4534
Author: gtully <ga...@gmail.com>
Authored: Fri Oct 17 16:54:18 2014 +0100
Committer: gtully <ga...@gmail.com>
Committed: Fri Oct 17 16:55:23 2014 +0100
----------------------------------------------------------------------
.../region/cursors/AbstractStoreCursor.java | 5 -
.../activemq/store/kahadb/KahaDBStore.java | 15 +-
.../activemq/bugs/AMQ5266SingleDestTest.java | 617 +++++++++++++++++++
3 files changed, 622 insertions(+), 15 deletions(-)
----------------------------------------------------------------------
http://git-wip-us.apache.org/repos/asf/activemq/blob/1d39f08c/activemq-broker/src/main/java/org/apache/activemq/broker/region/cursors/AbstractStoreCursor.java
----------------------------------------------------------------------
diff --git a/activemq-broker/src/main/java/org/apache/activemq/broker/region/cursors/AbstractStoreCursor.java b/activemq-broker/src/main/java/org/apache/activemq/broker/region/cursors/AbstractStoreCursor.java
index 9998152..f2df96e 100644
--- a/activemq-broker/src/main/java/org/apache/activemq/broker/region/cursors/AbstractStoreCursor.java
+++ b/activemq-broker/src/main/java/org/apache/activemq/broker/region/cursors/AbstractStoreCursor.java
@@ -310,11 +310,6 @@ public abstract class AbstractStoreCursor extends AbstractPendingMessageCursor i
long next = 1 + (Long)lastCachedIds[SYNC_ADD].getFutureOrSequenceLong();
if (Long.compare((Long)futureOrLong, next) == 0) {
setLastCachedId(SYNC_ADD, candidate);
- } else {
- // out of sequence, revert to sync state
- if (LOG.isDebugEnabled()) {
- LOG.debug("{} cursor order out of sync at seq {}, audit must suppress potential replay of {} messages from the store", this, next, pendingCachedIds.size());
- }
}
}
it.remove();
http://git-wip-us.apache.org/repos/asf/activemq/blob/1d39f08c/activemq-kahadb-store/src/main/java/org/apache/activemq/store/kahadb/KahaDBStore.java
----------------------------------------------------------------------
diff --git a/activemq-kahadb-store/src/main/java/org/apache/activemq/store/kahadb/KahaDBStore.java b/activemq-kahadb-store/src/main/java/org/apache/activemq/store/kahadb/KahaDBStore.java
index a18071b..4438292 100644
--- a/activemq-kahadb-store/src/main/java/org/apache/activemq/store/kahadb/KahaDBStore.java
+++ b/activemq-kahadb-store/src/main/java/org/apache/activemq/store/kahadb/KahaDBStore.java
@@ -656,23 +656,18 @@ public class KahaDBStore extends MessageDatabase implements PersistenceAdapter {
@Override
public void setBatch(final MessageId identity) throws IOException {
- final String key = identity.toProducerKey();
indexLock.writeLock().lock();
try {
pageFile.tx().execute(new Transaction.Closure<IOException>() {
@Override
public void execute(Transaction tx) throws IOException {
StoredDestination sd = getStoredDestination(dest, tx);
- Long location = sd.messageIdIndex.get(tx, key);
- if (location != null) {
- Long pending = sd.orderIndex.minPendingAdd();
- if (pending != null) {
- location = Math.min(location, pending-1);
- }
- sd.orderIndex.setBatch(tx, location);
- } else {
- LOG.warn("{} {} setBatch failed, location for {} not found in messageId index for {}", this, dest.getName(), identity.getFutureOrSequenceLong(), identity);
+ Long location = (Long) identity.getFutureOrSequenceLong();
+ Long pending = sd.orderIndex.minPendingAdd();
+ if (pending != null) {
+ location = Math.min(location, pending-1);
}
+ sd.orderIndex.setBatch(tx, location);
}
});
} finally {
http://git-wip-us.apache.org/repos/asf/activemq/blob/1d39f08c/activemq-unit-tests/src/test/java/org/apache/activemq/bugs/AMQ5266SingleDestTest.java
----------------------------------------------------------------------
diff --git a/activemq-unit-tests/src/test/java/org/apache/activemq/bugs/AMQ5266SingleDestTest.java b/activemq-unit-tests/src/test/java/org/apache/activemq/bugs/AMQ5266SingleDestTest.java
new file mode 100644
index 0000000..afcf54f
--- /dev/null
+++ b/activemq-unit-tests/src/test/java/org/apache/activemq/bugs/AMQ5266SingleDestTest.java
@@ -0,0 +1,617 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.activemq.bugs;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.TreeSet;
+import java.util.UUID;
+import java.util.concurrent.TimeUnit;
+import javax.jms.Message;
+import javax.jms.MessageConsumer;
+import javax.jms.MessageProducer;
+import javax.jms.Queue;
+import javax.jms.QueueConnection;
+import javax.jms.Session;
+import javax.jms.TextMessage;
+import org.apache.activemq.ActiveMQConnection;
+import org.apache.activemq.ActiveMQConnectionFactory;
+import org.apache.activemq.RedeliveryPolicy;
+import org.apache.activemq.broker.BrokerService;
+import org.apache.activemq.broker.TransportConnector;
+import org.apache.activemq.broker.region.policy.PolicyEntry;
+import org.apache.activemq.broker.region.policy.PolicyMap;
+import org.apache.activemq.command.ActiveMQQueue;
+import org.apache.activemq.store.jdbc.JDBCPersistenceAdapter;
+import org.apache.activemq.store.jdbc.adapter.DefaultJDBCAdapter;
+import org.apache.activemq.store.kahadb.KahaDBPersistenceAdapter;
+import org.apache.derby.jdbc.EmbeddedDataSource;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.Parameterized;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+
+import static org.junit.Assert.assertEquals;
+
+/**
+ Non transactional concurrent producer/consumer to single dest
+ */
+@RunWith(Parameterized.class)
+public class AMQ5266SingleDestTest {
+ static Logger LOG = LoggerFactory.getLogger(AMQ5266SingleDestTest.class);
+ String activemqURL;
+ BrokerService brokerService;
+ private EmbeddedDataSource dataSource;
+
+ public int numDests = 1;
+ public int messageSize = 10*1000;
+
+ @Parameterized.Parameter(0)
+ public int publisherMessagesPerThread = 1000;
+
+ @Parameterized.Parameter(1)
+ public int publisherThreadCount = 20;
+
+ @Parameterized.Parameter(2)
+ public int consumerThreadsPerQueue = 5;
+
+ @Parameterized.Parameter(3)
+ public int destMemoryLimit = 50 * 1024;
+
+ @Parameterized.Parameter(4)
+ public boolean useCache = true;
+
+ @Parameterized.Parameter(5)
+ public boolean useDefaultStore = false;
+
+ @Parameterized.Parameter(6)
+ public boolean optimizeDispatch = false;
+
+ @Parameterized.Parameters(name="#{0},producerThreads:{1},consumerThreads:{2},mL:{3},useCache:{4},useDefaultStore:{5},optimizedDispatch:{6}")
+ public static Iterable<Object[]> parameters() {
+ return Arrays.asList(new Object[][]{
+ {1000, 80, 80, 1024*1024*5, true, true, false},
+ });
+ }
+
+ public int consumerBatchSize = 25;
+
+ @Before
+ public void startBroker() throws Exception {
+ brokerService = new BrokerService();
+
+ dataSource = new EmbeddedDataSource();
+ dataSource.setDatabaseName("target/derbyDb");
+ dataSource.setCreateDatabase("create");
+
+ JDBCPersistenceAdapter jdbcPersistenceAdapter = new JDBCPersistenceAdapter();
+ jdbcPersistenceAdapter.setDataSource(dataSource);
+ jdbcPersistenceAdapter.setUseLock(false);
+
+ if (!useDefaultStore) {
+ brokerService.setPersistenceAdapter(jdbcPersistenceAdapter);
+ } else {
+ KahaDBPersistenceAdapter kahaDBPersistenceAdapter = (KahaDBPersistenceAdapter) brokerService.getPersistenceAdapter();
+ kahaDBPersistenceAdapter.setConcurrentStoreAndDispatchQueues(true);
+ }
+ brokerService.setDeleteAllMessagesOnStartup(true);
+ brokerService.setUseJmx(false);
+
+
+ PolicyMap policyMap = new PolicyMap();
+ PolicyEntry defaultEntry = new PolicyEntry();
+ defaultEntry.setUseConsumerPriority(false); // java.lang.IllegalArgumentException: Comparison method violates its general contract!
+ defaultEntry.setMaxProducersToAudit(publisherThreadCount);
+ defaultEntry.setEnableAudit(true);
+ defaultEntry.setUseCache(useCache);
+ defaultEntry.setMaxPageSize(1000);
+ defaultEntry.setOptimizedDispatch(optimizeDispatch);
+ defaultEntry.setMemoryLimit(destMemoryLimit);
+ defaultEntry.setExpireMessagesPeriod(0);
+ policyMap.setDefaultEntry(defaultEntry);
+ brokerService.setDestinationPolicy(policyMap);
+
+ brokerService.getSystemUsage().getMemoryUsage().setLimit(512 * 1024 * 1024);
+
+ TransportConnector transportConnector = brokerService.addConnector("tcp://0.0.0.0:0");
+ brokerService.start();
+ activemqURL = transportConnector.getPublishableConnectString();
+ }
+
+ @After
+ public void stopBroker() throws Exception {
+ if (brokerService != null) {
+ brokerService.stop();
+ }
+ try {
+ dataSource.setShutdownDatabase("shutdown");
+ dataSource.getConnection();
+ } catch (Exception ignored) {}
+ }
+
+ @Test
+ public void test() throws Exception {
+
+ String activemqQueues = "activemq";
+ for (int i=1;i<numDests;i++) {
+ activemqQueues +=",activemq"+i;
+ }
+
+ int consumerWaitForConsumption = 5 * 60 * 1000;
+
+ ExportQueuePublisher publisher = null;
+ ExportQueueConsumer consumer = null;
+
+ LOG.info("Publisher will publish " + (publisherMessagesPerThread * publisherThreadCount) + " messages to each queue specified.");
+ LOG.info("\nBuilding Publisher...");
+
+ publisher = new ExportQueuePublisher(activemqURL, activemqQueues, publisherMessagesPerThread, publisherThreadCount);
+
+ LOG.info("Building Consumer...");
+
+ consumer = new ExportQueueConsumer(activemqURL, activemqQueues, consumerThreadsPerQueue, consumerBatchSize, publisherMessagesPerThread * publisherThreadCount);
+
+ long totalStart = System.currentTimeMillis();
+
+ LOG.info("Starting Publisher...");
+
+ publisher.start();
+
+ LOG.info("Starting Consumer...");
+
+ consumer.start();
+
+ int distinctPublishedCount = 0;
+
+
+ LOG.info("Waiting For Publisher Completion...");
+
+ publisher.waitForCompletion();
+
+ List publishedIds = publisher.getIDs();
+ distinctPublishedCount = new TreeSet(publishedIds).size();
+
+ LOG.info("Publisher Complete. Published: " + publishedIds.size() + ", Distinct IDs Published: " + distinctPublishedCount);
+ LOG.info("Publisher duration: {}", TimeUnit.MILLISECONDS.toSeconds(System.currentTimeMillis() - totalStart));
+
+
+ long endWait = System.currentTimeMillis() + consumerWaitForConsumption;
+ while (!consumer.completed() && System.currentTimeMillis() < endWait) {
+ try {
+ int secs = (int) (endWait - System.currentTimeMillis()) / 1000;
+ LOG.info("Waiting For Consumer Completion. Time left: " + secs + " secs");
+ if (!useDefaultStore) {
+ DefaultJDBCAdapter.dumpTables(dataSource.getConnection());
+ }
+ Thread.sleep(1000);
+ } catch (Exception e) {
+ }
+ }
+
+ LOG.info("\nConsumer Complete: " + consumer.completed() +", Shutting Down.");
+
+ LOG.info("Total duration: {}", TimeUnit.MILLISECONDS.toSeconds(System.currentTimeMillis() - totalStart));
+
+ consumer.shutdown();
+
+ TimeUnit.SECONDS.sleep(2);
+ LOG.info("DB Contents START");
+ if (!useDefaultStore) {
+ DefaultJDBCAdapter.dumpTables(dataSource.getConnection());
+ }
+ LOG.info("DB Contents END");
+
+ LOG.info("Consumer Stats:");
+
+ for (Map.Entry<String, List<String>> entry : consumer.getIDs().entrySet()) {
+
+ List<String> idList = entry.getValue();
+
+ int distinctConsumed = new TreeSet<String>(idList).size();
+
+ StringBuilder sb = new StringBuilder();
+ sb.append(" Queue: " + entry.getKey() +
+ " -> Total Messages Consumed: " + idList.size() +
+ ", Distinct IDs Consumed: " + distinctConsumed);
+
+ int diff = distinctPublishedCount - distinctConsumed;
+ sb.append(" ( " + (diff > 0 ? diff : "NO") + " STUCK MESSAGES " + " ) ");
+ LOG.info(sb.toString());
+
+ assertEquals("expect to get all messages!", 0, diff);
+
+ }
+ }
+
+ public class ExportQueuePublisher {
+
+ private final String amqUser = ActiveMQConnection.DEFAULT_USER;
+ private final String amqPassword = ActiveMQConnection.DEFAULT_PASSWORD;
+ private ActiveMQConnectionFactory connectionFactory = null;
+ private String activemqURL = null;
+ private String activemqQueues = null;
+ // Collection of distinct IDs that the publisher has published.
+ // After a message is published, its UUID will be written to this list for tracking.
+ // This list of IDs (or distinct count) will be used to compare to the consumed list of IDs.
+ //private Set<String> ids = Collections.synchronizedSet(new TreeSet<String>());
+ private List<String> ids = Collections.synchronizedList(new ArrayList<String>());
+ private List<PublisherThread> threads;
+
+ public ExportQueuePublisher(String activemqURL, String activemqQueues, int messagesPerThread, int threadCount) throws Exception {
+
+ this.activemqURL = activemqURL;
+ this.activemqQueues = activemqQueues;
+
+ threads = new ArrayList<PublisherThread>();
+
+ // Build the threads and tell them how many messages to publish
+ for (int i = 0; i < threadCount; i++) {
+ PublisherThread pt = new PublisherThread(messagesPerThread);
+ threads.add(pt);
+ }
+ }
+
+ public List<String> getIDs() {
+ return ids;
+ }
+
+ // Kick off threads
+ public void start() throws Exception {
+
+ for (PublisherThread pt : threads) {
+ pt.start();
+ }
+ }
+
+ // Wait for threads to complete. They will complete once they've published all of their messages.
+ public void waitForCompletion() throws Exception {
+
+ for (PublisherThread pt : threads) {
+ pt.join();
+ pt.close();
+ }
+ }
+
+ private Session newSession(QueueConnection queueConnection) throws Exception {
+ return queueConnection.createSession(false, Session.AUTO_ACKNOWLEDGE);
+ }
+
+ private synchronized QueueConnection newQueueConnection() throws Exception {
+
+ if (connectionFactory == null) {
+ connectionFactory = new ActiveMQConnectionFactory(amqUser, amqPassword, activemqURL);
+ }
+
+ // Set the redelivery count to -1 (infinite), or else messages will start dropping
+ // after the queue has had a certain number of failures (default is 6)
+ RedeliveryPolicy policy = connectionFactory.getRedeliveryPolicy();
+ policy.setMaximumRedeliveries(-1);
+
+ QueueConnection amqConnection = connectionFactory.createQueueConnection();
+ amqConnection.start();
+ return amqConnection;
+ }
+
+ private class PublisherThread extends Thread {
+
+ private int count;
+ private QueueConnection qc;
+ private Session session;
+ private MessageProducer mp;
+
+ private PublisherThread(int count) throws Exception {
+
+ this.count = count;
+
+ // Each Thread has its own Connection and Session, so no sync worries
+ qc = newQueueConnection();
+ session = newSession(qc);
+
+ // In our code, when publishing to multiple queues,
+ // we're using composite destinations like below
+ Queue q = new ActiveMQQueue(activemqQueues);
+ mp = session.createProducer(q);
+ }
+
+ public void run() {
+
+ try {
+
+ // Loop until we've published enough messages
+ while (count-- > 0) {
+
+ TextMessage tm = session.createTextMessage(getMessageText());
+ String id = UUID.randomUUID().toString();
+ tm.setStringProperty("KEY", id);
+ ids.add(id); // keep track of the key to compare against consumer
+
+ mp.send(tm);
+ }
+ } catch (Exception e) {
+ e.printStackTrace();
+ }
+ }
+
+ // Called by waitForCompletion
+ public void close() {
+
+ try {
+ mp.close();
+ } catch (Exception e) {
+ }
+
+ try {
+ session.close();
+ } catch (Exception e) {
+ }
+
+ try {
+ qc.close();
+ } catch (Exception e) {
+ }
+ }
+ }
+
+ }
+
+ String messageText;
+ private String getMessageText() {
+
+ if (messageText == null) {
+
+ synchronized (this) {
+
+ if (messageText == null) {
+
+ StringBuilder sb = new StringBuilder();
+ for (int i = 0; i < messageSize; i++) {
+ sb.append("X");
+ }
+ messageText = sb.toString();
+ }
+ }
+ }
+
+ return messageText;
+ }
+
+
+ public class ExportQueueConsumer {
+
+ private final String amqUser = ActiveMQConnection.DEFAULT_USER;
+ private final String amqPassword = ActiveMQConnection.DEFAULT_PASSWORD;
+ private final int totalToExpect;
+ private ActiveMQConnectionFactory connectionFactory = null;
+ private String activemqURL = null;
+ private String activemqQueues = null;
+ private String[] queues = null;
+ // Map of IDs that were consumed, keyed by queue name.
+ // We'll compare these against what was published to know if any got stuck or dropped.
+ private Map<String, List<String>> idsByQueue = new HashMap<String, List<String>>();
+ private Map<String, List<ConsumerThread>> threads;
+
+ public ExportQueueConsumer(String activemqURL, String activemqQueues, int threadsPerQueue, int batchSize, int totalToExpect) throws Exception {
+
+ this.activemqURL = activemqURL;
+ this.activemqQueues = activemqQueues;
+ this.totalToExpect = totalToExpect;
+
+ queues = this.activemqQueues.split(",");
+
+ for (int i = 0; i < queues.length; i++) {
+ queues[i] = queues[i].trim();
+ }
+
+ threads = new HashMap<String, List<ConsumerThread>>();
+
+ // For each queue, create a list of threads and set up the list of ids
+ for (String q : queues) {
+
+ List<ConsumerThread> list = new ArrayList<ConsumerThread>();
+
+ idsByQueue.put(q, Collections.synchronizedList(new ArrayList<String>()));
+
+ for (int i = 0; i < threadsPerQueue; i++) {
+ list.add(new ConsumerThread(q, batchSize));
+ }
+
+ threads.put(q, list);
+ }
+ }
+
+ public Map<String, List<String>> getIDs() {
+ return idsByQueue;
+ }
+
+ // Start the threads
+ public void start() throws Exception {
+
+ for (List<ConsumerThread> list : threads.values()) {
+
+ for (ConsumerThread ct : list) {
+
+ ct.start();
+ }
+ }
+ }
+
+ // Tell the threads to stop
+ // Then wait for them to stop
+ public void shutdown() throws Exception {
+
+ for (List<ConsumerThread> list : threads.values()) {
+
+ for (ConsumerThread ct : list) {
+
+ ct.shutdown();
+ }
+ }
+
+ for (List<ConsumerThread> list : threads.values()) {
+
+ for (ConsumerThread ct : list) {
+
+ ct.join();
+ }
+ }
+ }
+
+ private Session newSession(QueueConnection queueConnection) throws Exception {
+ return queueConnection.createSession(false, Session.AUTO_ACKNOWLEDGE);
+ }
+
+ private synchronized QueueConnection newQueueConnection() throws Exception {
+
+ if (connectionFactory == null) {
+ connectionFactory = new ActiveMQConnectionFactory(amqUser, amqPassword, activemqURL);
+ }
+
+ // Set the redelivery count to -1 (infinite), or else messages will start dropping
+ // after the queue has had a certain number of failures (default is 6)
+ RedeliveryPolicy policy = connectionFactory.getRedeliveryPolicy();
+ policy.setMaximumRedeliveries(-1);
+
+ QueueConnection amqConnection = connectionFactory.createQueueConnection();
+ amqConnection.start();
+ return amqConnection;
+ }
+
+ public boolean completed() {
+ for (List<ConsumerThread> list : threads.values()) {
+
+ for (ConsumerThread ct : list) {
+
+ if (ct.isAlive()) {
+ LOG.info("thread for {} is still alive.", ct.qName);
+ return false;
+ }
+ }
+ }
+ return true;
+ }
+
+ private class ConsumerThread extends Thread {
+
+ private int batchSize;
+ private QueueConnection qc;
+ private Session session;
+ private MessageConsumer mc;
+ private List<String> idList;
+ private boolean shutdown = false;
+ private String qName;
+
+ private ConsumerThread(String queueName, int batchSize) throws Exception {
+
+ this.batchSize = batchSize;
+
+ // Each thread has its own connection and session
+ qName = queueName;
+ qc = newQueueConnection();
+ session = newSession(qc);
+ Queue q = session.createQueue(queueName + "?consumer.prefetchSize=" + batchSize);
+ mc = session.createConsumer(q);
+
+ idList = idsByQueue.get(queueName);
+ }
+
+ public void run() {
+
+ try {
+
+ int count = 0;
+
+ // Keep reading as long as it hasn't been told to shutdown
+ while (!shutdown) {
+
+ if (idList.size() >= totalToExpect) {
+ LOG.info("Got {} for q: {}", +idList.size(), qName);
+ break;
+ }
+ Message m = mc.receive(4000);
+
+ if (m != null) {
+
+ // We received a non-null message, add the ID to our list
+
+ idList.add(m.getStringProperty("KEY"));
+
+ count++;
+
+ // If we've reached our batch size, commit the batch and reset the count
+
+ if (count == batchSize) {
+ count = 0;
+ }
+ } else {
+
+ // We didn't receive anything this time, commit any current batch and reset the count
+
+ count = 0;
+
+ // Sleep a little before trying to read after not getting a message
+
+ try {
+ if (idList.size() < totalToExpect) {
+ LOG.info("did not receive on {}, current count: {}", qName, idList.size());
+ }
+ //sleep(3000);
+ } catch (Exception e) {
+ }
+ }
+ }
+ } catch (Exception e) {
+ e.printStackTrace();
+ } finally {
+
+ // Once we exit, close everything
+ close();
+ }
+ }
+
+ public void shutdown() {
+ shutdown = true;
+ }
+
+ public void close() {
+
+ try {
+ mc.close();
+ } catch (Exception e) {
+ }
+
+ try {
+ session.close();
+ } catch (Exception e) {
+ }
+
+ try {
+ qc.close();
+ } catch (Exception e) {
+
+ }
+ }
+ }
+ }
+}