/*
* ModeShape (http://www.modeshape.org)
*
* Licensed 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.modeshape.jcr.cache.document;
import java.util.Collections;
import java.util.HashSet;
import java.util.Iterator;
import java.util.Set;
import java.util.UUID;
import java.util.concurrent.atomic.AtomicReference;
import javax.transaction.RollbackException;
import javax.transaction.Status;
import javax.transaction.SystemException;
import javax.transaction.Transaction;
import org.modeshape.common.annotation.Immutable;
import org.modeshape.common.logging.Logger;
import org.modeshape.jcr.ExecutionContext;
import org.modeshape.jcr.JcrI18n;
import org.modeshape.jcr.api.value.DateTime;
import org.modeshape.jcr.cache.CachedNode;
import org.modeshape.jcr.cache.ChildReference;
import org.modeshape.jcr.cache.NodeCache;
import org.modeshape.jcr.cache.NodeKey;
import org.modeshape.jcr.cache.SessionCache;
import org.modeshape.jcr.cache.SessionEnvironment;
import org.modeshape.jcr.txn.Transactions;
import org.modeshape.jcr.value.NameFactory;
import org.modeshape.jcr.value.Path;
import org.modeshape.jcr.value.PathFactory;
import org.modeshape.jcr.value.ValueFactories;
/**
*
*/
public abstract class AbstractSessionCache implements SessionCache, DocumentCache {
@Immutable
protected static final class BasicSaveContext implements SaveContext {
private final DateTime now;
private final String userId;
protected BasicSaveContext( ExecutionContext context ) {
this.now = context.getValueFactories().getDateFactory().create();
this.userId = context.getSecurityContext().getUserName();
}
@Override
public DateTime getTime() {
return now;
}
@Override
public String getUserId() {
return userId;
}
}
private final WorkspaceCache sharedWorkspaceCache;
private final AtomicReference<WorkspaceCache> workspaceCache = new AtomicReference<WorkspaceCache>();
private final NameFactory nameFactory;
private final PathFactory pathFactory;
private final Path rootPath;
private final SessionEnvironment sessionContext;
private ExecutionContext context;
private AtomicReference<Transactions.TransactionFunction> completeTransactionFunction = new AtomicReference<>();
protected AbstractSessionCache( ExecutionContext context,
WorkspaceCache sharedWorkspaceCache,
SessionEnvironment sessionContext ) {
this.context = context;
this.sharedWorkspaceCache = sharedWorkspaceCache;
this.workspaceCache.set(sharedWorkspaceCache);
ValueFactories factories = this.context.getValueFactories();
this.nameFactory = factories.getNameFactory();
this.pathFactory = factories.getPathFactory();
this.rootPath = this.pathFactory.createRootPath();
this.sessionContext = sessionContext;
assert this.sessionContext != null;
checkForTransaction();
}
protected abstract Logger logger();
/**
* Signal that this session cache should check for an existing transaction and use the appropriate workspace cache. If there
* is a (new to this session) transaction, then this session will use a transaction-specific workspace cache (shared by other
* sessions participating in the same transaction), and upon completion of the transaction the session will switch back to the
* shared workspace cache.
*/
@Override
public void checkForTransaction() {
try {
Transactions transactions = sessionContext.getTransactions();
Transaction txn = transactions.getTransactionManager().getTransaction();
if (txn != null && txn.getStatus() == Status.STATUS_ACTIVE) {
// There is an active transaction, so we need a transaction-specific workspace cache ...
workspaceCache.set(sessionContext.getTransactionalWorkspaceCacheFactory()
.getTransactionalWorkspaceCache(sharedWorkspaceCache));
// only register the function if there's an active ModeShape transaction because we need to run the
// function *only after* ISPN has committed its transaction & updated the cache
// if there isn't an active ModeShape transaction, one will become active later during "save"
// otherwise, "save" is never called meaning this cache should be discarded
Transactions.Transaction modeshapeTx = transactions.currentTransaction();
if (modeshapeTx != null) {
if (this.completeTransactionFunction.get() == null) {
// create and register the complete transaction function only once
this.completeTransactionFunction.compareAndSet(null, new Transactions.TransactionFunction() {
@Override
public void execute() {
completeTransaction();
}
});
// always run this function, regardless whether the transaction succeeds or not
modeshapeTx.uponCompletion(this.completeTransactionFunction.get());
}
}
} else {
// There is no active transaction, so just use the shared workspace cache ...
completeTransaction();
}
} catch (SystemException e) {
logger().error(e, JcrI18n.errorDeterminingCurrentTransactionAssumingNone, workspaceName(), e.getMessage());
} catch (RollbackException e) {
logger().error(e, JcrI18n.errorDeterminingCurrentTransactionAssumingNone, workspaceName(), e.getMessage());
}
}
/**
* Signal that the transaction that was active and in which this session participated has completed and that this session
* should no longer use a transaction-specific workspace cache.
*/
protected void completeTransaction() {
workspaceCache.set(sharedWorkspaceCache);
}
@Override
public final SessionCache unwrap() {
return this;
}
protected final String workspaceName() {
return workspaceCache().getWorkspaceName();
}
@Override
public final ExecutionContext getContext() {
return context;
}
@Override
public final WorkspaceCache workspaceCache() {
return workspaceCache.get();
}
final DocumentTranslator translator() {
return workspaceCache().translator();
}
final ExecutionContext context() {
return context;
}
final NameFactory nameFactory() {
return nameFactory;
}
final PathFactory pathFactory() {
return pathFactory;
}
final Path rootPath() {
return rootPath;
}
SessionEnvironment sessionContext() {
return sessionContext;
}
@Override
public final void addContextData( String key,
String value ) {
this.context = context.with(key, value);
}
@Override
public NodeKey createNodeKey() {
return getRootKey().withId(generateIdentifier());
}
@Override
public NodeKey createNodeKeyWithIdentifier( String identifier ) {
return getRootKey().withId(identifier);
}
@Override
public NodeKey createNodeKeyWithSource( String sourceName ) {
String sourceKey = NodeKey.keyForSourceName(sourceName);
return getRootKey().withSourceKeyAndId(sourceKey, generateIdentifier());
}
@Override
public NodeKey createNodeKey( String sourceName,
String identifier ) {
String sourceKey = NodeKey.keyForSourceName(sourceName);
if (identifier == null) identifier = generateIdentifier();
return getRootKey().withSourceKeyAndId(sourceKey, identifier);
}
protected String generateIdentifier() {
return UUID.randomUUID().toString();
}
@Override
public NodeKey getRootKey() {
return workspaceCache().getRootKey();
}
@Override
public NodeCache getWorkspace() {
return workspaceCache();
}
@Override
public CachedNode getNode( NodeKey key ) {
return workspaceCache().getNode(key);
}
@Override
public CachedNode getNode( ChildReference reference ) {
return getNode(reference.getKey());
}
@Override
public Set<NodeKey> getNodeKeysAtAndBelow( NodeKey nodeKey ) {
CachedNode node = this.getNode(nodeKey);
if (node == null) {
return Collections.emptySet();
}
Set<NodeKey> result = new HashSet<NodeKey>();
result.add(nodeKey);
for (ChildReference reference : node.getChildReferences(this)) {
NodeKey childKey = reference.getKey();
result.addAll(getNodeKeysAtAndBelow(childKey));
}
return result;
}
@Override
public abstract SessionNode mutable( NodeKey key );
@Override
public Iterator<NodeKey> getAllNodeKeys() {
return getAllNodeKeysAtAndBelow(getRootKey());
}
@Override
public Iterator<NodeKey> getAllNodeKeysAtAndBelow( NodeKey startingKey ) {
return new NodeCacheIterator(this, startingKey);
}
@Override
public final void clear( CachedNode node ) {
doClear(node);
WorkspaceCache wscache = workspaceCache.get();
if (wscache != sharedWorkspaceCache) {
assert wscache instanceof TransactionalWorkspaceCache;
wscache.clear();
}
}
@Override
public final void clear() {
doClear();
WorkspaceCache wscache = workspaceCache.get();
if (wscache != sharedWorkspaceCache) {
assert wscache instanceof TransactionalWorkspaceCache;
wscache.clear();
}
}
protected abstract void doClear( CachedNode node );
protected abstract void doClear();
}