/*
* Quasar: lightweight threads and actors for the JVM.
* Copyright (c) 2013-2015, Parallel Universe Software Co. All rights reserved.
*
* This program and the accompanying materials are dual-licensed under
* either the terms of the Eclipse Public License v1.0 as published by
* the Eclipse Foundation
*
* or (per the licensee's choosing)
*
* under the terms of the GNU Lesser General Public License version 3.0
* as published by the Free Software Foundation.
*/
package co.paralleluniverse.remote.galaxy;
import co.paralleluniverse.actors.Actor;
import co.paralleluniverse.actors.ActorRef;
import co.paralleluniverse.actors.spi.ActorRegistry;
import co.paralleluniverse.fibers.Fiber;
import co.paralleluniverse.fibers.SuspendExecution;
import co.paralleluniverse.galaxy.AbstractCacheListener;
import co.paralleluniverse.galaxy.Cache;
import co.paralleluniverse.galaxy.CacheListener;
import co.paralleluniverse.galaxy.StoreTransaction;
import co.paralleluniverse.galaxy.TimeoutException;
import co.paralleluniverse.galaxy.quasar.Grid;
import co.paralleluniverse.galaxy.quasar.Store;
import co.paralleluniverse.io.serialization.Serialization;
import co.paralleluniverse.strands.concurrent.ReentrantLock;
import java.nio.ByteBuffer;
import java.util.concurrent.Callable;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.locks.Condition;
import org.kohsuke.MetaInfServices;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
*
* @author pron
*/
@MetaInfServices
public class GlxGlobalRegistry extends ActorRegistry {
static volatile GlxGlobalRegistry INSTANCE;
private static final ConcurrentHashMap<String, CacheEntry> rootCache = new ConcurrentHashMap<>();
private static final Logger LOG = LoggerFactory.getLogger(GlxGlobalRegistry.class);
private static final ReentrantLock lock = new ReentrantLock();
private final Grid grid;
@SuppressWarnings("LeakingThisInConstructor")
public GlxGlobalRegistry() {
assert INSTANCE == null;
try {
grid = Grid.getInstance();
} catch (InterruptedException ex) {
throw new RuntimeException(ex);
}
INSTANCE = this;
}
@Override
public <Message> void register(Actor<Message, ?> actor, ActorRef<Message> actorRef) throws SuspendExecution {
final String rootName = actorRef.getName();
LOG.info("Registering actor {} at root {}", actorRef, rootName);
final Store store = grid.store();
StoreTransaction txn = store.beginTransaction();
lock.lock();
try {
try {
Object globalId = getGlobalId(actor);
final long root = store.getRoot(rootName, globalId != null ? (Long) globalId : -1, txn);
// assert globalId == null || ((Long) globalId) == root; -- it's OK to replace the actor's globalId -- until it's too late
setGlobalId(actor, root);
store.getx(root, txn);
store.set(root, Serialization.getInstance().write(actorRef), txn);
final long version = store.getVersion(root);
LOG.debug("Registered actor {} at rootId {}", actorRef, Long.toHexString(root));
store.commit(txn);
updateCache(rootName, new CacheEntry(actorRef, root, version)); // <--- comment out to test "distribution" on a single node
} catch (TimeoutException e) {
LOG.error("Registering actor {} at root {} failed due to timeout", actorRef, rootName);
store.rollback(txn);
store.abort(txn);
throw new RuntimeException("Actor registration failed");
}
} catch (InterruptedException e) {
throw new RuntimeException(e);
} finally {
lock.unlock();
}
}
@Override
public <Message> void unregister(Actor<Message, ?> actor, final ActorRef<Message> actorRef) {
new Fiber<Void>() {
@Override
protected Void run() throws SuspendExecution, InterruptedException {
unregister0(actorRef);
return null;
}
};
}
private void unregister0(ActorRef<?> actor) throws SuspendExecution {
final String rootName = actor.getName();
LOG.info("Unregistering {}", rootName);
final Store store = grid.store();
StoreTransaction txn = store.beginTransaction();
try {
try {
final long root = store.getRoot(rootName, txn);
store.set(root, (byte[]) null, txn);
store.commit(txn);
} catch (TimeoutException e) {
LOG.error("Unregistering {} failed due to timeout", rootName);
store.rollback(txn);
store.abort(txn);
throw new RuntimeException("Actor unregistration failed");
}
} catch (InterruptedException e) {
throw new RuntimeException(e);
}
}
@Override
public ActorRef<?> tryGetActor(String name) throws SuspendExecution {
ActorRef<?> actor = tryCache(name);
if (actor != null)
return actor;
return updateCache(name, tryGetActor0(name));
}
@Override
public ActorRef<?> getActor(String name) throws InterruptedException, SuspendExecution {
// try {
return getActor(name, 0, null);
// } catch (java.util.concurrent.TimeoutException e) {
// throw new AssertionError(e);
// }
}
@Override
public ActorRef<?> getActor(String name, long timeout, TimeUnit unit) throws InterruptedException, SuspendExecution {
ActorRef<?> actor = tryCache(name);
if (actor != null)
return actor;
final CacheEntry actorEntry = getActor0(name, timeout, unit);
if (actorEntry == null) {
return null;
}
return updateCache(name, actorEntry);
}
@Override
public <T extends ActorRef<?>> T getOrRegisterActor(String name, Callable<T> actorFactory) throws SuspendExecution {
ActorRef<?> actor = tryCache(name);
if (actor != null)
return (T) actor;
return updateCache(name, getOrRegisterActor0(name, actorFactory));
}
private ActorRef<?> tryCache(String name) {
CacheEntry entry = rootCache.get(name);
if (entry == null)
return null;
return entry.version == grid.store().getVersion(entry.root) ? entry.actor : null;
}
private CacheEntry tryGetActor0(final String rootName) throws SuspendExecution, RuntimeException {
final Store store = grid.store();
final StoreTransaction txn = store.beginTransaction();
try {
try {
final long root = store.getRoot(rootName, txn);
final byte[] buf = store.gets(root, txn);
if (buf == null) {
LOG.debug("Store returned null for root {}", rootName);
return null;
}
final long version = store.getVersion(root);
store.commit(txn);
LOG.debug("Store returned a buffer ({} bytes) for root {}", buf.length, rootName);
if (buf.length == 0)
return null; // TODO: Galaxy should return null
ActorRef<?> actor = deserActor(rootName, buf);
return new CacheEntry(actor, root, version);
} catch (TimeoutException e) {
LOG.error("Getting actor {} failed due to timeout", rootName);
store.rollback(txn);
store.abort(txn);
throw new RuntimeException("Actor discovery failed");
}
} catch (InterruptedException e) {
throw new RuntimeException(e);
}
}
private CacheEntry getActor0(final String rootName, long timeout, TimeUnit unit) throws SuspendExecution, RuntimeException, InterruptedException {
final long deadline = unit != null ? System.nanoTime() + unit.toNanos(timeout) : 0;
final Store store = grid.store();
final long root;
final ReentrantLock lck0 = new ReentrantLock();
final Condition cond = lck0.newCondition();
boolean listening = false;
final StoreTransaction txn = store.beginTransaction();
try {
root = store.getRoot(rootName, txn);
final CacheListener listener = new AbstractCacheListener() {
@Override
public void evicted(Cache cache, long id) {
invalidated(cache, id);
}
@Override
public void invalidated(Cache cache, long id) {
grid.getDelegate().store().getAsync(id);
}
@Override
public void received(Cache cache, long id, long version, ByteBuffer data) {
if (data != null && data.remaining() > 0) {
LOG.debug("Received root {} ({})", rootName, Long.toHexString(id));
lck0.lock();
try {
cond.signalAll();
} finally {
lck0.unlock();
}
store.setListener(root, null);
}
}
};
listening = (store.setListenerIfAbsent(root, listener) == listener);
store.commit(txn);
} catch (TimeoutException e) {
LOG.error("Getting actor {} failed due to timeout", rootName);
store.rollback(txn);
store.abort(txn);
throw new RuntimeException("Actor discovery failed");
}
try {
byte[] buf = store.gets(root, null);
long version = store.getVersion(root);
store.release(root);
if (listening) {
lck0.lock();
try {
while (buf == null || buf.length == 0) {
LOG.debug("Store returned null for root {}", rootName);
if (deadline > 0) {
final long now = System.nanoTime();
if (now > deadline)
return null; // throw new java.util.concurrent.TimeoutException();
cond.await(deadline - now, TimeUnit.NANOSECONDS);
} else
cond.await();
buf = store.gets(root, null);
version = store.getVersion(root);
store.release(root);
}
} finally {
lck0.unlock();
}
} else
assert buf != null && buf.length > 0;
final ActorRef<?> actor = deserActor(rootName, buf);
return new CacheEntry(actor, root, version);
} catch (TimeoutException e) {
LOG.error("Getting actor {} failed due to timeout", rootName);
throw new RuntimeException("Actor discovery failed");
}
}
private CacheEntry getOrRegisterActor0(final String rootName, Callable<? extends ActorRef<?>> actorFactory) throws SuspendExecution, RuntimeException {
final Store store = grid.store();
final StoreTransaction txn = store.beginTransaction();
try {
try {
final long root = store.getRoot(rootName, txn);
final ActorRef<?> actor;
final byte[] buf = store.getx(root, txn);
long version = store.getVersion(root);
if (buf == null || buf.length == 0) {
try {
actor = actorFactory.call();
} catch (Exception e) {
throw new RuntimeException("Exception while creating actor", e);
}
LOG.debug("Store returned null for root {}. Registering actor {} at rootId {}", rootName, actor, root);
store.set(root, Serialization.getInstance().write(actor), txn);
version = store.getVersion(root);
} else
actor = deserActor(rootName, buf);
store.commit(txn);
return new CacheEntry(actor, root, version);
} catch (TimeoutException e) {
LOG.error("Getting actor {} failed due to timeout", rootName);
store.rollback(txn);
store.abort(txn);
throw new RuntimeException("Actor discovery/registration failed");
}
} catch (InterruptedException e) {
throw new RuntimeException(e);
}
}
private <Message> ActorRef<Message> deserActor(final String rootName, byte[] buf) {
try {
final ActorRef<Message> actor = (ActorRef<Message>) Serialization.getInstance().read(buf);
LOG.debug("Deserialized actor {} for root {}", actor, rootName);
return actor;
} catch (Exception e) {
LOG.error("Deserializing actor at root " + rootName + " has failed with exception", e);
return null;
}
}
private <T extends ActorRef<?>> T updateCache(final String rootName, CacheEntry entry) {
rootCache.put(rootName, entry);
return (T) entry.actor;
}
@Override
public void shutdown() {
grid.cluster().goOffline();
}
static class CacheEntry {
final ActorRef<?> actor;
final long root;
final long version;
public CacheEntry(ActorRef<?> actor, long root, long version) {
this.actor = actor;
this.root = root;
this.version = version;
}
}
}