/**
* 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.store.kahadb;
import java.io.DataInput;
import java.io.DataOutput;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.TreeMap;
import java.util.Map.Entry;
import java.util.concurrent.atomic.AtomicBoolean;
import org.apache.activemq.command.SubscriptionInfo;
import org.apache.activemq.command.TransactionId;
import org.apache.activemq.store.kahadb.data.KahaAddMessageCommand;
import org.apache.activemq.store.kahadb.data.KahaDestination;
import org.apache.activemq.store.kahadb.data.KahaRemoveDestinationCommand;
import org.apache.activemq.store.kahadb.data.KahaRemoveMessageCommand;
import org.apache.activemq.store.kahadb.data.KahaSubscriptionCommand;
import org.apache.activemq.util.ByteSequence;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.apache.activemq.store.kahadb.disk.index.BTreeIndex;
import org.apache.activemq.store.kahadb.disk.page.PageFile;
import org.apache.activemq.store.kahadb.disk.page.Transaction;
import org.apache.activemq.store.kahadb.disk.util.LongMarshaller;
import org.apache.activemq.store.kahadb.disk.util.StringMarshaller;
import org.apache.activemq.store.kahadb.disk.util.VariableMarshaller;
public class TempMessageDatabase {
private static final Logger LOG = LoggerFactory.getLogger(TempMessageDatabase.class);
public static final int CLOSED_STATE = 1;
public static final int OPEN_STATE = 2;
protected BTreeIndex<String, StoredDestination> destinations;
protected PageFile pageFile;
protected File directory;
boolean enableIndexWriteAsync = true;
int setIndexWriteBatchSize = PageFile.DEFAULT_WRITE_BATCH_SIZE;
protected AtomicBoolean started = new AtomicBoolean();
protected AtomicBoolean opened = new AtomicBoolean();
public TempMessageDatabase() {
}
public void start() throws Exception {
if (started.compareAndSet(false, true)) {
load();
}
}
public void stop() throws Exception {
if (started.compareAndSet(true, false)) {
unload();
}
}
private void loadPageFile() throws IOException {
synchronized (indexMutex) {
final PageFile pageFile = getPageFile();
pageFile.load();
pageFile.tx().execute(new Transaction.Closure<IOException>() {
public void execute(Transaction tx) throws IOException {
destinations = new BTreeIndex<String, StoredDestination>(pageFile, tx.allocate().getPageId());
destinations.setKeyMarshaller(StringMarshaller.INSTANCE);
destinations.setValueMarshaller(new StoredDestinationMarshaller());
destinations.load(tx);
}
});
pageFile.flush();
storedDestinations.clear();
}
}
/**
* @throws IOException
*/
public void open() throws IOException {
if( opened.compareAndSet(false, true) ) {
loadPageFile();
}
}
public void load() throws IOException {
synchronized (indexMutex) {
open();
pageFile.unload();
pageFile.delete();
loadPageFile();
}
}
public void close() throws IOException, InterruptedException {
if( opened.compareAndSet(true, false)) {
synchronized (indexMutex) {
pageFile.unload();
}
}
}
public void unload() throws IOException, InterruptedException {
synchronized (indexMutex) {
if( pageFile.isLoaded() ) {
close();
}
}
}
public void processAdd(final KahaAddMessageCommand command, TransactionId txid, final ByteSequence data) throws IOException {
if (txid!=null) {
synchronized (indexMutex) {
ArrayList<Operation> inflightTx = getInflightTx(txid);
inflightTx.add(new AddOpperation(command, data));
}
} else {
synchronized (indexMutex) {
pageFile.tx().execute(new Transaction.Closure<IOException>() {
public void execute(Transaction tx) throws IOException {
upadateIndex(tx, command, data);
}
});
}
}
}
public void processRemove(final KahaRemoveMessageCommand command, TransactionId txid) throws IOException {
if (txid!=null) {
synchronized (indexMutex) {
ArrayList<Operation> inflightTx = getInflightTx(txid);
inflightTx.add(new RemoveOpperation(command));
}
} else {
synchronized (indexMutex) {
pageFile.tx().execute(new Transaction.Closure<IOException>() {
public void execute(Transaction tx) throws IOException {
updateIndex(tx, command);
}
});
}
}
}
public void process(final KahaRemoveDestinationCommand command) throws IOException {
synchronized (indexMutex) {
pageFile.tx().execute(new Transaction.Closure<IOException>() {
public void execute(Transaction tx) throws IOException {
updateIndex(tx, command);
}
});
}
}
public void process(final KahaSubscriptionCommand command) throws IOException {
synchronized (indexMutex) {
pageFile.tx().execute(new Transaction.Closure<IOException>() {
public void execute(Transaction tx) throws IOException {
updateIndex(tx, command);
}
});
}
}
public void processCommit(TransactionId key) throws IOException {
synchronized (indexMutex) {
ArrayList<Operation> inflightTx = inflightTransactions.remove(key);
if (inflightTx == null) {
inflightTx = preparedTransactions.remove(key);
}
if (inflightTx == null) {
return;
}
final ArrayList<Operation> messagingTx = inflightTx;
pageFile.tx().execute(new Transaction.Closure<IOException>() {
public void execute(Transaction tx) throws IOException {
for (Operation op : messagingTx) {
op.execute(tx);
}
}
});
}
}
public void processPrepare(TransactionId key) {
synchronized (indexMutex) {
ArrayList<Operation> tx = inflightTransactions.remove(key);
if (tx != null) {
preparedTransactions.put(key, tx);
}
}
}
public void processRollback(TransactionId key) {
synchronized (indexMutex) {
ArrayList<Operation> tx = inflightTransactions.remove(key);
if (tx == null) {
preparedTransactions.remove(key);
}
}
}
// /////////////////////////////////////////////////////////////////
// These methods do the actual index updates.
// /////////////////////////////////////////////////////////////////
protected final Object indexMutex = new Object();
private final HashSet<Integer> journalFilesBeingReplicated = new HashSet<Integer>();
private void upadateIndex(Transaction tx, KahaAddMessageCommand command, ByteSequence data) throws IOException {
StoredDestination sd = getStoredDestination(command.getDestination(), tx);
// Skip adding the message to the index if this is a topic and there are
// no subscriptions.
if (sd.subscriptions != null && sd.ackPositions.isEmpty()) {
return;
}
// Add the message.
long id = sd.nextMessageId++;
Long previous = sd.messageIdIndex.put(tx, command.getMessageId(), id);
if( previous == null ) {
sd.orderIndex.put(tx, id, new MessageRecord(command.getMessageId(), data));
} else {
// restore the previous value.. Looks like this was a redo of a previously
// added message. We don't want to assing it a new id as the other indexes would
// be wrong..
sd.messageIdIndex.put(tx, command.getMessageId(), previous);
}
}
private void updateIndex(Transaction tx, KahaRemoveMessageCommand command) throws IOException {
StoredDestination sd = getStoredDestination(command.getDestination(), tx);
if (!command.hasSubscriptionKey()) {
// In the queue case we just remove the message from the index..
Long sequenceId = sd.messageIdIndex.remove(tx, command.getMessageId());
if (sequenceId != null) {
sd.orderIndex.remove(tx, sequenceId);
}
} else {
// In the topic case we need remove the message once it's been acked
// by all the subs
Long sequence = sd.messageIdIndex.get(tx, command.getMessageId());
// Make sure it's a valid message id...
if (sequence != null) {
String subscriptionKey = command.getSubscriptionKey();
Long prev = sd.subscriptionAcks.put(tx, subscriptionKey, sequence);
// The following method handles deleting un-referenced messages.
removeAckByteSequence(tx, sd, subscriptionKey, prev);
// Add it to the new location set.
addAckByteSequence(sd, sequence, subscriptionKey);
}
}
}
private void updateIndex(Transaction tx, KahaRemoveDestinationCommand command) throws IOException {
StoredDestination sd = getStoredDestination(command.getDestination(), tx);
sd.orderIndex.clear(tx);
sd.orderIndex.unload(tx);
tx.free(sd.orderIndex.getPageId());
sd.messageIdIndex.clear(tx);
sd.messageIdIndex.unload(tx);
tx.free(sd.messageIdIndex.getPageId());
if (sd.subscriptions != null) {
sd.subscriptions.clear(tx);
sd.subscriptions.unload(tx);
tx.free(sd.subscriptions.getPageId());
sd.subscriptionAcks.clear(tx);
sd.subscriptionAcks.unload(tx);
tx.free(sd.subscriptionAcks.getPageId());
}
String key = key(command.getDestination());
storedDestinations.remove(key);
destinations.remove(tx, key);
}
private void updateIndex(Transaction tx, KahaSubscriptionCommand command) throws IOException {
StoredDestination sd = getStoredDestination(command.getDestination(), tx);
// If set then we are creating it.. otherwise we are destroying the sub
if (command.hasSubscriptionInfo()) {
String subscriptionKey = command.getSubscriptionKey();
sd.subscriptions.put(tx, subscriptionKey, command);
long ackByteSequence=-1;
if (!command.getRetroactive()) {
ackByteSequence = sd.nextMessageId-1;
}
sd.subscriptionAcks.put(tx, subscriptionKey, ackByteSequence);
addAckByteSequence(sd, ackByteSequence, subscriptionKey);
} else {
// delete the sub...
String subscriptionKey = command.getSubscriptionKey();
sd.subscriptions.remove(tx, subscriptionKey);
Long prev = sd.subscriptionAcks.remove(tx, subscriptionKey);
if( prev!=null ) {
removeAckByteSequence(tx, sd, subscriptionKey, prev);
}
}
}
public HashSet<Integer> getJournalFilesBeingReplicated() {
return journalFilesBeingReplicated;
}
// /////////////////////////////////////////////////////////////////
// StoredDestination related implementation methods.
// /////////////////////////////////////////////////////////////////
private final HashMap<String, StoredDestination> storedDestinations = new HashMap<String, StoredDestination>();
class StoredSubscription {
SubscriptionInfo subscriptionInfo;
String lastAckId;
ByteSequence lastAckByteSequence;
ByteSequence cursor;
}
static class MessageRecord {
final String messageId;
final ByteSequence data;
public MessageRecord(String messageId, ByteSequence location) {
this.messageId=messageId;
this.data=location;
}
@Override
public String toString() {
return "["+messageId+","+data+"]";
}
}
static protected class MessageKeysMarshaller extends VariableMarshaller<MessageRecord> {
static final MessageKeysMarshaller INSTANCE = new MessageKeysMarshaller();
public MessageRecord readPayload(DataInput dataIn) throws IOException {
return new MessageRecord(dataIn.readUTF(), ByteSequenceMarshaller.INSTANCE.readPayload(dataIn));
}
public void writePayload(MessageRecord object, DataOutput dataOut) throws IOException {
dataOut.writeUTF(object.messageId);
ByteSequenceMarshaller.INSTANCE.writePayload(object.data, dataOut);
}
}
static class StoredDestination {
long nextMessageId;
BTreeIndex<Long, MessageRecord> orderIndex;
BTreeIndex<String, Long> messageIdIndex;
// These bits are only set for Topics
BTreeIndex<String, KahaSubscriptionCommand> subscriptions;
BTreeIndex<String, Long> subscriptionAcks;
HashMap<String, Long> subscriptionCursors;
TreeMap<Long, HashSet<String>> ackPositions;
}
protected class StoredDestinationMarshaller extends VariableMarshaller<StoredDestination> {
public Class<StoredDestination> getType() {
return StoredDestination.class;
}
public StoredDestination readPayload(DataInput dataIn) throws IOException {
StoredDestination value = new StoredDestination();
value.orderIndex = new BTreeIndex<Long, MessageRecord>(pageFile, dataIn.readLong());
value.messageIdIndex = new BTreeIndex<String, Long>(pageFile, dataIn.readLong());
if (dataIn.readBoolean()) {
value.subscriptions = new BTreeIndex<String, KahaSubscriptionCommand>(pageFile, dataIn.readLong());
value.subscriptionAcks = new BTreeIndex<String, Long>(pageFile, dataIn.readLong());
}
return value;
}
public void writePayload(StoredDestination value, DataOutput dataOut) throws IOException {
dataOut.writeLong(value.orderIndex.getPageId());
dataOut.writeLong(value.messageIdIndex.getPageId());
if (value.subscriptions != null) {
dataOut.writeBoolean(true);
dataOut.writeLong(value.subscriptions.getPageId());
dataOut.writeLong(value.subscriptionAcks.getPageId());
} else {
dataOut.writeBoolean(false);
}
}
}
static class ByteSequenceMarshaller extends VariableMarshaller<ByteSequence> {
final static ByteSequenceMarshaller INSTANCE = new ByteSequenceMarshaller();
public ByteSequence readPayload(DataInput dataIn) throws IOException {
byte data[] = new byte[dataIn.readInt()];
dataIn.readFully(data);
return new ByteSequence(data);
}
public void writePayload(ByteSequence object, DataOutput dataOut) throws IOException {
dataOut.writeInt(object.getLength());
dataOut.write(object.getData(), object.getOffset(), object.getLength());
}
}
static class KahaSubscriptionCommandMarshaller extends VariableMarshaller<KahaSubscriptionCommand> {
final static KahaSubscriptionCommandMarshaller INSTANCE = new KahaSubscriptionCommandMarshaller();
public KahaSubscriptionCommand readPayload(DataInput dataIn) throws IOException {
KahaSubscriptionCommand rc = new KahaSubscriptionCommand();
rc.mergeFramed((InputStream)dataIn);
return rc;
}
public void writePayload(KahaSubscriptionCommand object, DataOutput dataOut) throws IOException {
object.writeFramed((OutputStream)dataOut);
}
}
protected StoredDestination getStoredDestination(KahaDestination destination, Transaction tx) throws IOException {
String key = key(destination);
StoredDestination rc = storedDestinations.get(key);
if (rc == null) {
boolean topic = destination.getType() == KahaDestination.DestinationType.TOPIC || destination.getType() == KahaDestination.DestinationType.TEMP_TOPIC;
rc = loadStoredDestination(tx, key, topic);
// Cache it. We may want to remove/unload destinations from the
// cache that are not used for a while
// to reduce memory usage.
storedDestinations.put(key, rc);
}
return rc;
}
/**
* @param tx
* @param key
* @param topic
* @return
* @throws IOException
*/
private StoredDestination loadStoredDestination(Transaction tx, String key, boolean topic) throws IOException {
// Try to load the existing indexes..
StoredDestination rc = destinations.get(tx, key);
if (rc == null) {
// Brand new destination.. allocate indexes for it.
rc = new StoredDestination();
rc.orderIndex = new BTreeIndex<Long, MessageRecord>(pageFile, tx.allocate());
rc.messageIdIndex = new BTreeIndex<String, Long>(pageFile, tx.allocate());
if (topic) {
rc.subscriptions = new BTreeIndex<String, KahaSubscriptionCommand>(pageFile, tx.allocate());
rc.subscriptionAcks = new BTreeIndex<String, Long>(pageFile, tx.allocate());
}
destinations.put(tx, key, rc);
}
// Configure the marshalers and load.
rc.orderIndex.setKeyMarshaller(LongMarshaller.INSTANCE);
rc.orderIndex.setValueMarshaller(MessageKeysMarshaller.INSTANCE);
rc.orderIndex.load(tx);
// Figure out the next key using the last entry in the destination.
Entry<Long, MessageRecord> lastEntry = rc.orderIndex.getLast(tx);
if( lastEntry!=null ) {
rc.nextMessageId = lastEntry.getKey()+1;
}
rc.messageIdIndex.setKeyMarshaller(StringMarshaller.INSTANCE);
rc.messageIdIndex.setValueMarshaller(LongMarshaller.INSTANCE);
rc.messageIdIndex.load(tx);
// If it was a topic...
if (topic) {
rc.subscriptions.setKeyMarshaller(StringMarshaller.INSTANCE);
rc.subscriptions.setValueMarshaller(KahaSubscriptionCommandMarshaller.INSTANCE);
rc.subscriptions.load(tx);
rc.subscriptionAcks.setKeyMarshaller(StringMarshaller.INSTANCE);
rc.subscriptionAcks.setValueMarshaller(LongMarshaller.INSTANCE);
rc.subscriptionAcks.load(tx);
rc.ackPositions = new TreeMap<Long, HashSet<String>>();
rc.subscriptionCursors = new HashMap<String, Long>();
for (Iterator<Entry<String, Long>> iterator = rc.subscriptionAcks.iterator(tx); iterator.hasNext();) {
Entry<String, Long> entry = iterator.next();
addAckByteSequence(rc, entry.getValue(), entry.getKey());
}
}
return rc;
}
/**
* @param sd
* @param messageSequence
* @param subscriptionKey
*/
private void addAckByteSequence(StoredDestination sd, Long messageSequence, String subscriptionKey) {
HashSet<String> hs = sd.ackPositions.get(messageSequence);
if (hs == null) {
hs = new HashSet<String>();
sd.ackPositions.put(messageSequence, hs);
}
hs.add(subscriptionKey);
}
/**
* @param tx
* @param sd
* @param subscriptionKey
* @param sequenceId
* @throws IOException
*/
private void removeAckByteSequence(Transaction tx, StoredDestination sd, String subscriptionKey, Long sequenceId) throws IOException {
// Remove the sub from the previous location set..
if (sequenceId != null) {
HashSet<String> hs = sd.ackPositions.get(sequenceId);
if (hs != null) {
hs.remove(subscriptionKey);
if (hs.isEmpty()) {
HashSet<String> firstSet = sd.ackPositions.values().iterator().next();
sd.ackPositions.remove(sequenceId);
// Did we just empty out the first set in the
// ordered list of ack locations? Then it's time to
// delete some messages.
if (hs == firstSet) {
// Find all the entries that need to get deleted.
ArrayList<Entry<Long, MessageRecord>> deletes = new ArrayList<Entry<Long, MessageRecord>>();
for (Iterator<Entry<Long, MessageRecord>> iterator = sd.orderIndex.iterator(tx); iterator.hasNext();) {
Entry<Long, MessageRecord> entry = iterator.next();
if (entry.getKey().compareTo(sequenceId) <= 0) {
// We don't do the actually delete while we are
// iterating the BTree since
// iterating would fail.
deletes.add(entry);
}
}
// Do the actual deletes.
for (Entry<Long, MessageRecord> entry : deletes) {
sd.messageIdIndex.remove(tx,entry.getValue().messageId);
sd.orderIndex.remove(tx,entry.getKey());
}
}
}
}
}
}
private String key(KahaDestination destination) {
return destination.getType().getNumber() + ":" + destination.getName();
}
// /////////////////////////////////////////////////////////////////
// Transaction related implementation methods.
// /////////////////////////////////////////////////////////////////
protected final LinkedHashMap<TransactionId, ArrayList<Operation>> inflightTransactions = new LinkedHashMap<TransactionId, ArrayList<Operation>>();
protected final LinkedHashMap<TransactionId, ArrayList<Operation>> preparedTransactions = new LinkedHashMap<TransactionId, ArrayList<Operation>>();
private ArrayList<Operation> getInflightTx(TransactionId key) {
ArrayList<Operation> tx = inflightTransactions.get(key);
if (tx == null) {
tx = new ArrayList<Operation>();
inflightTransactions.put(key, tx);
}
return tx;
}
abstract class Operation {
abstract public void execute(Transaction tx) throws IOException;
}
class AddOpperation extends Operation {
final KahaAddMessageCommand command;
private final ByteSequence data;
public AddOpperation(KahaAddMessageCommand command, ByteSequence location) {
this.command = command;
this.data = location;
}
public void execute(Transaction tx) throws IOException {
upadateIndex(tx, command, data);
}
public KahaAddMessageCommand getCommand() {
return command;
}
}
class RemoveOpperation extends Operation {
final KahaRemoveMessageCommand command;
public RemoveOpperation(KahaRemoveMessageCommand command) {
this.command = command;
}
public void execute(Transaction tx) throws IOException {
updateIndex(tx, command);
}
public KahaRemoveMessageCommand getCommand() {
return command;
}
}
// /////////////////////////////////////////////////////////////////
// Initialization related implementation methods.
// /////////////////////////////////////////////////////////////////
private PageFile createPageFile() {
PageFile index = new PageFile(directory, "temp-db");
index.setEnableWriteThread(isEnableIndexWriteAsync());
index.setWriteBatchSize(getIndexWriteBatchSize());
index.setEnableDiskSyncs(false);
index.setEnableRecoveryFile(false);
return index;
}
public File getDirectory() {
return directory;
}
public void setDirectory(File directory) {
this.directory = directory;
}
public void setIndexWriteBatchSize(int setIndexWriteBatchSize) {
this.setIndexWriteBatchSize = setIndexWriteBatchSize;
}
public int getIndexWriteBatchSize() {
return setIndexWriteBatchSize;
}
public void setEnableIndexWriteAsync(boolean enableIndexWriteAsync) {
this.enableIndexWriteAsync = enableIndexWriteAsync;
}
boolean isEnableIndexWriteAsync() {
return enableIndexWriteAsync;
}
public PageFile getPageFile() {
if (pageFile == null) {
pageFile = createPageFile();
}
return pageFile;
}
}