org.neo4j.kernel.impl.api.KernelTransactions Maven / Gradle / Ivy
/*
* Copyright (c) 2002-2016 "Neo Technology,"
* Network Engine for Objects in Lund AB [http://neotechnology.com]
*
* This file is part of Neo4j.
*
* Neo4j is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see
* This class maintains references to all running transactions and provides capabilities for enumerating them.
* During normal operation, acquiring new transactions and enumerating live ones requires same amount of
* synchronization as {@link ConcurrentHashMap} provides for insertions and iterations.
*
* Live list is not guaranteed to be exact.
*/
public class KernelTransactions extends LifecycleAdapter implements Factory
{
private final Locks locks;
private final ConstraintIndexCreator constraintIndexCreator;
private final StatementOperationParts statementOperations;
private final SchemaWriteGuard schemaWriteGuard;
private final TransactionHeaderInformationFactory transactionHeaderInformationFactory;
private final TransactionCommitProcess transactionCommitProcess;
private final IndexConfigStore indexConfigStore;
private final LegacyIndexProviderLookup legacyIndexProviderLookup;
private final TransactionHooks hooks;
private final TransactionMonitor transactionMonitor;
private final LifeSupport dataSourceLife;
private final Tracers tracers;
private final StorageEngine storageEngine;
private final Procedures procedures;
private final TransactionIdStore transactionIdStore;
private final Set allTransactions = newSetFromMap( new ConcurrentHashMap<>() );
public KernelTransactions( Locks locks,
ConstraintIndexCreator constraintIndexCreator,
StatementOperationParts statementOperations,
SchemaWriteGuard schemaWriteGuard,
TransactionHeaderInformationFactory txHeaderFactory,
TransactionCommitProcess transactionCommitProcess,
IndexConfigStore indexConfigStore,
LegacyIndexProviderLookup legacyIndexProviderLookup,
TransactionHooks hooks,
TransactionMonitor transactionMonitor,
LifeSupport dataSourceLife,
Tracers tracers,
StorageEngine storageEngine,
Procedures procedures,
TransactionIdStore transactionIdStore )
{
this.locks = locks;
this.constraintIndexCreator = constraintIndexCreator;
this.statementOperations = statementOperations;
this.schemaWriteGuard = schemaWriteGuard;
this.transactionHeaderInformationFactory = txHeaderFactory;
this.transactionCommitProcess = transactionCommitProcess;
this.indexConfigStore = indexConfigStore;
this.legacyIndexProviderLookup = legacyIndexProviderLookup;
this.hooks = hooks;
this.transactionMonitor = transactionMonitor;
this.dataSourceLife = dataSourceLife;
this.tracers = tracers;
this.storageEngine = storageEngine;
this.procedures = procedures;
this.transactionIdStore = transactionIdStore;
}
@Override
public KernelTransaction newInstance()
{
assertDatabaseIsRunning();
Locks.Client locksClient = locks.newClient();
LegacyIndexTransactionState legacyIndexTransactionState =
new LegacyIndexTransactionStateImpl( indexConfigStore, legacyIndexProviderLookup );
long lastTransactionIdWhenStarted = transactionIdStore.getLastCommittedTransactionId();
KernelTransactionImplementation tx = new KernelTransactionImplementation( statementOperations, schemaWriteGuard,
locksClient, hooks, constraintIndexCreator, procedures, transactionHeaderInformationFactory,
transactionCommitProcess, transactionMonitor, legacyIndexTransactionState,
this, Clock.SYSTEM_CLOCK, tracers.transactionTracer, storageEngine, lastTransactionIdWhenStarted );
allTransactions.add( tx );
return tx;
}
/**
* Signals that given transaction is closed and should be removed from the set of running transactions.
*
* @param tx the closed transaction.
* @throws IllegalStateException if given transaction is not in the set of active transactions.
*/
public void transactionClosed( KernelTransaction tx )
{
boolean removed = allTransactions.remove( tx );
if ( !removed )
{
throw new IllegalStateException( "Transaction: " + tx + " is not present in the " +
"set of known active transactions: " + allTransactions );
}
}
/**
* Give an approximate set of all transactions currently running.
* This is not guaranteed to be exact, as transactions may stop and start while this set is gathered.
*
* @return the set of open transactions.
*/
public Set activeTransactions()
{
return Collections.unmodifiableSet( new HashSet<>( allTransactions ) );
}
/**
* Dispose of all active transactions. This is done on shutdown or on internal events (like an HA mode switch) that
* require transactions to be re-created.
*/
public void disposeAll()
{
allTransactions.forEach( KernelTransaction::markForTermination );
}
@Override
public void shutdown() throws Throwable
{
disposeAll();
}
private void assertDatabaseIsRunning()
{
// TODO: Copied over from original source in NeoXADS - this should probably use DBAvailability,
// rather than this.
// Note, if you change this, you need a separate mechanism to stop transactions from being started during
// Kernel#stop().
if ( !dataSourceLife.isRunning() )
{
throw new DatabaseShutdownException();
}
}
}