/*
* JBoss, Home of Professional Open Source
* Copyright 2011 Red Hat Inc. and/or its affiliates and other
* contributors as indicated by the @author tags. All rights reserved.
* See the copyright.txt in the distribution for a full listing of
* individual contributors.
*
* This is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This software is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package org.infinispan.transaction;
import org.infinispan.commands.write.WriteCommand;
import org.infinispan.container.entries.CacheEntry;
import org.infinispan.container.versioning.EntryVersion;
import org.infinispan.container.versioning.EntryVersionsMap;
import org.infinispan.container.versioning.VersionGenerator;
import org.infinispan.container.versioning.gmu.GMUVersionGenerator;
import org.infinispan.remoting.transport.Address;
import org.infinispan.transaction.xa.CacheTransaction;
import org.infinispan.transaction.xa.GlobalTransaction;
import org.infinispan.util.concurrent.ConcurrentHashSet;
import org.infinispan.util.concurrent.ConcurrentMapFactory;
import org.infinispan.util.logging.Log;
import org.infinispan.util.logging.LogFactory;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.List;
import java.util.Map;
import java.util.Set;
import static org.infinispan.transaction.gmu.GMUHelper.toGMUVersionGenerator;
/**
* Base class for local and remote transaction. Impl note: The aggregated modification list and lookedUpEntries are not
* instantiated here but in subclasses. This is done in order to take advantage of the fact that, for remote
* transactions we already know the size of the modifications list at creation time.
*
* @author Mircea.Markus@jboss.com
* @author Galder Zamarreño
* @author Pedro Ruivo
* @author Sebastiano Peluso
* @since 4.2
*/
public abstract class AbstractCacheTransaction implements CacheTransaction {
protected final GlobalTransaction tx;
private static Log log = LogFactory.getLog(AbstractCacheTransaction.class);
private static final boolean trace = log.isTraceEnabled();
private static final int INITIAL_LOCK_CAPACITY = 4;
protected List<WriteCommand> modifications;
protected Map<Object, CacheEntry> lookedUpEntries;
protected Set<Object> affectedKeys = null;
protected Set<Object> lockedKeys;
protected Set<Object> backupKeyLocks = null;
private boolean txComplete = false;
protected volatile boolean prepared;
private volatile boolean needToNotifyWaiters = false;
final int viewId;
private EntryVersionsMap updatedEntryVersions;
private EntryVersion transactionVersion;
public AbstractCacheTransaction(GlobalTransaction tx, int viewId) {
this.tx = tx;
this.viewId = viewId;
}
@Override
public GlobalTransaction getGlobalTransaction() {
return tx;
}
@Override
public List<WriteCommand> getModifications() {
return modifications;
}
public void setModifications(WriteCommand[] modifications) {
this.modifications = Arrays.asList(modifications);
}
@Override
public Map<Object, CacheEntry> getLookedUpEntries() {
return lookedUpEntries;
}
@Override
public CacheEntry lookupEntry(Object key) {
if (lookedUpEntries == null) return null;
return lookedUpEntries.get(key);
}
@Override
public void removeLookedUpEntry(Object key) {
if (lookedUpEntries != null) lookedUpEntries.remove(key);
}
@Override
public void clearLookedUpEntries() {
lookedUpEntries = null;
}
@Override
public boolean ownsLock(Object key) {
return getLockedKeys().contains(key);
}
@Override
public void notifyOnTransactionFinished() {
if (trace) log.tracef("Transaction %s has completed, notifying listening threads.", tx);
txComplete = true; //this one is cheap but does not guarantee visibility
if (needToNotifyWaiters) {
synchronized (this) {
txComplete = true; //in this case we want to guarantee visibility to other threads
this.notifyAll();
}
}
}
@Override
public boolean waitForLockRelease(Object key, long lockAcquisitionTimeout) throws InterruptedException {
if (txComplete) return true; //using an unsafe optimisation: if it's true, we for sure have the latest read of the value without needing memory barriers
final boolean potentiallyLocked = hasLockOrIsLockBackup(key);
if (trace) log.tracef("Transaction gtx=%s potentially locks key %s? %s", tx, key, potentiallyLocked);
if (potentiallyLocked) {
synchronized (this) {
// Check again after acquiring a lock on the monitor that the transaction has completed.
// If it has completed, all of its locks would have been released.
needToNotifyWaiters = true;
//The order in which these booleans are verified is critical as we take advantage of it to avoid otherwise needed locking
if (txComplete) {
needToNotifyWaiters = false;
return true;
}
this.wait(lockAcquisitionTimeout);
// Check again in case of spurious thread signalling
return txComplete;
}
}
return true;
}
@Override
public int getViewId() {
return viewId;
}
@Override
public void addBackupLockForKey(Object key) {
if (backupKeyLocks == null) backupKeyLocks = createSet(INITIAL_LOCK_CAPACITY);
backupKeyLocks.add(key);
}
public void registerLockedKey(Object key) {
if (lockedKeys == null) lockedKeys = createSet(INITIAL_LOCK_CAPACITY);
if (trace) log.tracef("Registering locked key: %s", key);
lockedKeys.add(key);
}
@Override
public Set<Object> getLockedKeys() {
return lockedKeys == null ? Collections.emptySet() : lockedKeys;
}
@Override
public void clearLockedKeys() {
if (trace) log.tracef("Clearing locked keys: %s", lockedKeys);
lockedKeys = null;
}
private boolean hasLockOrIsLockBackup(Object key) {
return (lockedKeys != null && lockedKeys.contains(key)) || (backupKeyLocks != null && backupKeyLocks.contains(key));
}
public Set<Object> getAffectedKeys() {
return affectedKeys == null ? Collections.emptySet() : affectedKeys;
}
public void addAffectedKey(Object key) {
initAffectedKeys();
affectedKeys.add(key);
}
public void addAllAffectedKeys(Collection<Object> keys) {
initAffectedKeys();
for (Object key : keys) {
affectedKeys.add(key);
}
}
private void initAffectedKeys() {
if (affectedKeys == null) affectedKeys = createSet(INITIAL_LOCK_CAPACITY);
}
@Override
public EntryVersionsMap getUpdatedEntryVersions() {
return updatedEntryVersions;
}
@Override
public void setUpdatedEntryVersions(EntryVersionsMap updatedEntryVersions) {
this.updatedEntryVersions = updatedEntryVersions;
}
@Override
public void addReadKey(Object key) {
// No-op
}
@Override
public boolean keyRead(Object key) {
return false;
}
@Override
public void markPrepareSent() {
//no-op
}
@Override
public boolean wasPrepareSent() {
return false; // no-op
}
@Override
public EntryVersion calculateVersionToRead(VersionGenerator versionGenerator) {
GMUVersionGenerator gmuVersionGenerator = toGMUVersionGenerator(versionGenerator);
return gmuVersionGenerator.calculateMaxVersionToRead(transactionVersion, getReadFrom());
}
@Override
public Collection<Object> getReadKeys() {
return Collections.emptyList();
}
@Override
public void addReadFrom(Address address) {
//no-op
}
@Override
public Set<Address> getReadFrom() {
return Collections.emptySet();
}
@Override
public void setTransactionVersion(EntryVersion version) {
if (log.isDebugEnabled()) {
log.debugf("[%s] new transaction version: %s", tx.prettyPrint(), version);
}
transactionVersion = version;
}
@Override
public EntryVersion getTransactionVersion() {
if (log.isDebugEnabled()) {
log.debugf("[%s] get transaction version: %s", tx.prettyPrint(), transactionVersion);
}
return transactionVersion;
}
@Override
public boolean hasAlreadyReadOnThisNode() {
return false;
}
@Override
public void setAlreadyReadOnThisNode(boolean value) {
//no-op
}
protected final Map<Object, CacheEntry> createMapEntries(int size) {
return ConcurrentMapFactory.makeConcurrentMap(size);
}
protected final Map<Object, CacheEntry> createMapEntries(Map<Object, CacheEntry> map) {
Map<Object, CacheEntry> newMap = ConcurrentMapFactory.makeConcurrentMap(map.size());
newMap.putAll(map);
return newMap;
}
protected final Set<Object> createSet(int size) {
return new ConcurrentHashSet<Object>(size);
}
}