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GraphDatabaseFacade.java
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GraphDatabaseFacade.java
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/*
* Copyright (c) 2002-2018 "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 <http://www.gnu.org/licenses/>.
*/
package org.neo4j.kernel.impl.factory;
import java.io.File;
import java.net.URL;
import java.util.Collections;
import java.util.Map;
import java.util.NoSuchElementException;
import java.util.concurrent.TimeUnit;
import java.util.function.Supplier;
import org.neo4j.collection.primitive.PrimitiveLongCollections;
import org.neo4j.collection.primitive.PrimitiveLongIterator;
import org.neo4j.collection.primitive.PrimitiveLongResourceIterator;
import org.neo4j.function.Suppliers;
import org.neo4j.function.ThrowingAction;
import org.neo4j.graphdb.ConstraintViolationException;
import org.neo4j.graphdb.DependencyResolver;
import org.neo4j.graphdb.Label;
import org.neo4j.graphdb.MultipleFoundException;
import org.neo4j.graphdb.Node;
import org.neo4j.graphdb.NotFoundException;
import org.neo4j.graphdb.QueryExecutionException;
import org.neo4j.graphdb.Relationship;
import org.neo4j.graphdb.RelationshipType;
import org.neo4j.graphdb.Resource;
import org.neo4j.graphdb.ResourceIterable;
import org.neo4j.graphdb.ResourceIterator;
import org.neo4j.graphdb.ResourceUtils;
import org.neo4j.graphdb.Result;
import org.neo4j.graphdb.Transaction;
import org.neo4j.graphdb.TransactionTerminatedException;
import org.neo4j.graphdb.event.KernelEventHandler;
import org.neo4j.graphdb.event.TransactionEventHandler;
import org.neo4j.graphdb.index.IndexManager;
import org.neo4j.graphdb.schema.Schema;
import org.neo4j.graphdb.security.URLAccessValidationError;
import org.neo4j.graphdb.traversal.BidirectionalTraversalDescription;
import org.neo4j.graphdb.traversal.TraversalDescription;
import org.neo4j.helpers.collection.PrefetchingResourceIterator;
import org.neo4j.internal.kernel.api.IndexQuery;
import org.neo4j.internal.kernel.api.InternalIndexState;
import org.neo4j.internal.kernel.api.NodeCursor;
import org.neo4j.internal.kernel.api.NodeLabelIndexCursor;
import org.neo4j.internal.kernel.api.exceptions.InvalidTransactionTypeKernelException;
import org.neo4j.internal.kernel.api.exceptions.KernelException;
import org.neo4j.internal.kernel.api.exceptions.schema.ConstraintValidationException;
import org.neo4j.internal.kernel.api.security.SecurityContext;
import org.neo4j.kernel.GraphDatabaseQueryService;
import org.neo4j.kernel.api.KernelTransaction;
import org.neo4j.kernel.api.ReadOperations;
import org.neo4j.kernel.api.Statement;
import org.neo4j.kernel.api.exceptions.EntityNotFoundException;
import org.neo4j.kernel.api.exceptions.Status;
import org.neo4j.kernel.api.exceptions.index.IndexNotFoundKernelException;
import org.neo4j.kernel.api.exceptions.schema.SchemaKernelException;
import org.neo4j.kernel.api.exceptions.schema.SchemaRuleNotFoundException;
import org.neo4j.kernel.api.explicitindex.AutoIndexing;
import org.neo4j.kernel.api.schema.SchemaDescriptorFactory;
import org.neo4j.kernel.api.schema.index.IndexDescriptor;
import org.neo4j.kernel.configuration.Config;
import org.neo4j.kernel.guard.Guard;
import org.neo4j.kernel.impl.api.TokenAccess;
import org.neo4j.kernel.impl.core.NodeProxy;
import org.neo4j.kernel.impl.core.RelationshipProxy;
import org.neo4j.kernel.impl.core.ThreadToStatementContextBridge;
import org.neo4j.kernel.impl.coreapi.AutoIndexerFacade;
import org.neo4j.kernel.impl.coreapi.IndexManagerImpl;
import org.neo4j.kernel.impl.coreapi.IndexProviderImpl;
import org.neo4j.kernel.impl.coreapi.InternalTransaction;
import org.neo4j.kernel.impl.coreapi.PlaceboTransaction;
import org.neo4j.kernel.impl.coreapi.PropertyContainerLocker;
import org.neo4j.kernel.impl.coreapi.ReadOnlyIndexFacade;
import org.neo4j.kernel.impl.coreapi.ReadOnlyRelationshipIndexFacade;
import org.neo4j.kernel.impl.coreapi.RelationshipAutoIndexerFacade;
import org.neo4j.kernel.impl.coreapi.StandardNodeActions;
import org.neo4j.kernel.impl.coreapi.StandardRelationshipActions;
import org.neo4j.kernel.impl.coreapi.TopLevelTransaction;
import org.neo4j.kernel.impl.coreapi.schema.SchemaImpl;
import org.neo4j.kernel.impl.query.Neo4jTransactionalContextFactory;
import org.neo4j.kernel.impl.query.TransactionalContext;
import org.neo4j.kernel.impl.query.TransactionalContextFactory;
import org.neo4j.kernel.impl.query.clientconnection.ClientConnectionInfo;
import org.neo4j.kernel.impl.store.StoreId;
import org.neo4j.kernel.impl.traversal.BidirectionalTraversalDescriptionImpl;
import org.neo4j.kernel.impl.traversal.MonoDirectionalTraversalDescription;
import org.neo4j.kernel.impl.util.ValueUtils;
import org.neo4j.kernel.internal.GraphDatabaseAPI;
import org.neo4j.storageengine.api.EntityType;
import org.neo4j.values.storable.Value;
import org.neo4j.values.storable.Values;
import org.neo4j.values.virtual.MapValue;
import static java.lang.String.format;
import static org.neo4j.graphdb.factory.GraphDatabaseSettings.transaction_timeout;
import static org.neo4j.helpers.collection.Iterators.emptyResourceIterator;
import static org.neo4j.internal.kernel.api.security.SecurityContext.AUTH_DISABLED;
import static org.neo4j.kernel.impl.api.explicitindex.InternalAutoIndexing.NODE_AUTO_INDEX;
import static org.neo4j.kernel.impl.api.explicitindex.InternalAutoIndexing.RELATIONSHIP_AUTO_INDEX;
import static org.neo4j.kernel.impl.api.operations.KeyReadOperations.NO_SUCH_LABEL;
import static org.neo4j.kernel.impl.api.operations.KeyReadOperations.NO_SUCH_PROPERTY_KEY;
/**
* Implementation of the GraphDatabaseService/GraphDatabaseService interfaces - the "Core API". Given an {@link SPI}
* implementation, this provides users with
* a clean facade to interact with the database.
*/
public class GraphDatabaseFacade implements GraphDatabaseAPI
{
private static final PropertyContainerLocker locker = new PropertyContainerLocker();
private Schema schema;
private Supplier<IndexManager> indexManager;
private NodeProxy.NodeActions nodeActions;
private RelationshipProxy.RelationshipActions relActions;
private SPI spi;
private TransactionalContextFactory contextFactory;
private Config config;
/**
* This is what you need to implemenent to get your very own {@link GraphDatabaseFacade}. This SPI exists as a thin
* layer to make it easy to provide
* alternate {@link org.neo4j.graphdb.GraphDatabaseService} instances without having to re-implement this whole API
* implementation.
*/
public interface SPI
{
/**
* Check if database is available, waiting up to {@code timeout} if it isn't. If the timeout expires before
* database available, this returns false
*/
boolean databaseIsAvailable( long timeout );
DependencyResolver resolver();
StoreId storeId();
File storeDir();
/** Eg. Neo4j Enterprise HA, Neo4j Community Standalone.. */
String name();
void shutdown();
/**
* Begin a new kernel transaction with specified timeout in milliseconds.
* If a transaction is already associated to the current context
* (meaning, non-null is returned from {@link #currentTransaction()}), this should fail.
*
* @throws org.neo4j.graphdb.TransactionFailureException if unable to begin, or a transaction already exists.
* @see SPI#beginTransaction(KernelTransaction.Type, SecurityContext)
*/
KernelTransaction beginTransaction( KernelTransaction.Type type, SecurityContext securityContext,
long timeout );
/**
* Retrieve the transaction associated with the current context. For the classic implementation of the Core API,
* the context is the current thread.
* Must not return null, and must return the underlying transaction even if it has been terminated.
*
* @throws org.neo4j.graphdb.NotInTransactionException if no transaction present
* @throws org.neo4j.graphdb.DatabaseShutdownException if the database has been shut down
*/
KernelTransaction currentTransaction();
/** true if {@link #currentTransaction()} would return a transaction. */
boolean isInOpenTransaction();
/** Acquire a statement to perform work with */
Statement currentStatement();
/** Execute a cypher statement */
Result executeQuery( String query, Map<String,Object> parameters, TransactionalContext context );
/** Execute a cypher statement */
Result executeQuery( String query, MapValue parameters, TransactionalContext context );
AutoIndexing autoIndexing();
void registerKernelEventHandler( KernelEventHandler handler );
void unregisterKernelEventHandler( KernelEventHandler handler );
<T> void registerTransactionEventHandler( TransactionEventHandler<T> handler );
<T> void unregisterTransactionEventHandler( TransactionEventHandler<T> handler );
URL validateURLAccess( URL url ) throws URLAccessValidationError;
GraphDatabaseQueryService queryService();
}
public GraphDatabaseFacade()
{
}
/**
* Create a new Core API facade, backed by the given SPI.
* <p>
* Any required dependencies are resolved using the resolver obtained from the SPI.
*/
public final void init( SPI spi )
{
DependencyResolver resolver = spi.resolver();
init(
spi,
resolver.resolveDependency( Guard.class ),
resolver.resolveDependency( ThreadToStatementContextBridge.class ),
resolver.resolveDependency( Config.class )
);
}
/**
* Create a new Core API facade, backed by the given SPI and using pre-resolved dependencies
*/
public void init( SPI spi, Guard guard, ThreadToStatementContextBridge txBridge, Config config )
{
this.spi = spi;
this.config = config;
Supplier<Statement> statementSupplier = spi::currentStatement;
Supplier<KernelTransaction> transactionSupplier = spi::currentTransaction;
ThrowingAction<RuntimeException> assertTransactionOpen = this::assertTransactionOpen;
this.schema = new SchemaImpl( statementSupplier );
this.relActions = new StandardRelationshipActions( statementSupplier, transactionSupplier, assertTransactionOpen,
id -> new NodeProxy( nodeActions, id ), this );
this.nodeActions = new StandardNodeActions( statementSupplier, transactionSupplier, assertTransactionOpen, relActions, this );
this.indexManager = Suppliers.lazySingleton( () ->
{
IndexProviderImpl idxProvider = new IndexProviderImpl( this, statementSupplier );
AutoIndexerFacade<Node> nodeAutoIndexer = new AutoIndexerFacade<>(
() -> new ReadOnlyIndexFacade<>( idxProvider.getOrCreateNodeIndex( NODE_AUTO_INDEX, null ) ),
spi.autoIndexing().nodes() );
RelationshipAutoIndexerFacade relAutoIndexer = new RelationshipAutoIndexerFacade(
() -> new ReadOnlyRelationshipIndexFacade(
idxProvider.getOrCreateRelationshipIndex( RELATIONSHIP_AUTO_INDEX, null ) ),
spi.autoIndexing().relationships() );
return new IndexManagerImpl( statementSupplier, idxProvider, nodeAutoIndexer, relAutoIndexer );
} );
this.contextFactory = Neo4jTransactionalContextFactory.create( spi, guard, txBridge, locker );
}
@Override
public Node createNode()
{
KernelTransaction transaction = spi.currentTransaction();
try ( Statement ignore = transaction.acquireStatement() )
{
return new NodeProxy( nodeActions, transaction.dataWrite().nodeCreate() );
}
catch ( InvalidTransactionTypeKernelException e )
{
throw new ConstraintViolationException( e.getMessage(), e );
}
}
@Override
public Long createNodeId()
{
KernelTransaction transaction = spi.currentTransaction();
try ( Statement ignore = transaction.acquireStatement() )
{
return transaction.dataWrite().nodeCreate();
}
catch ( InvalidTransactionTypeKernelException e )
{
throw new ConstraintViolationException( e.getMessage(), e );
}
}
@Override
public Node createNode( Label... labels )
{
try ( Statement statement = spi.currentStatement() )
{
long nodeId = statement.dataWriteOperations().nodeCreate();
for ( Label label : labels )
{
int labelId = statement.tokenWriteOperations().labelGetOrCreateForName( label.name() );
try
{
statement.dataWriteOperations().nodeAddLabel( nodeId, labelId );
}
catch ( EntityNotFoundException e )
{
throw new NotFoundException( "No node with id " + nodeId + " found.", e );
}
}
return new NodeProxy( nodeActions, nodeId );
}
catch ( ConstraintValidationException e )
{
throw new ConstraintViolationException( "Unable to add label.", e );
}
catch ( SchemaKernelException e )
{
throw new IllegalArgumentException( e );
}
catch ( InvalidTransactionTypeKernelException e )
{
throw new ConstraintViolationException( e.getMessage(), e );
}
}
@Override
public Node getNodeById( long id )
{
if ( id < 0 )
{
throw new NotFoundException( format( "Node %d not found", id ),
new EntityNotFoundException( EntityType.NODE, id ) );
}
KernelTransaction ktx = spi.currentTransaction();
assertTransactionOpen( ktx );
try ( Statement ignore = ktx.acquireStatement() )
{
if ( !ktx.dataRead().nodeExists( id ) )
{
throw new NotFoundException( format( "Node %d not found", id ),
new EntityNotFoundException( EntityType.NODE, id ) );
}
return new NodeProxy( nodeActions, id );
}
}
@Override
public Relationship getRelationshipById( long id )
{
if ( id < 0 )
{
throw new NotFoundException( format( "Relationship %d not found", id ),
new EntityNotFoundException( EntityType.RELATIONSHIP, id ) );
}
try ( Statement statement = spi.currentStatement() )
{
try
{
RelationshipProxy relationship = new RelationshipProxy( relActions, id );
statement.readOperations().relationshipVisit( id, relationship );
return relationship;
}
catch ( EntityNotFoundException e )
{
throw new NotFoundException( format( "Relationship %d not found", id ), e );
}
}
}
@Override
public IndexManager index()
{
return indexManager.get();
}
@Override
public Schema schema()
{
assertTransactionOpen();
return schema;
}
@Override
public boolean isAvailable( long timeoutMillis )
{
return spi.databaseIsAvailable( timeoutMillis );
}
@Override
public void shutdown()
{
spi.shutdown();
}
@Override
public Transaction beginTx()
{
return beginTransaction( KernelTransaction.Type.explicit, AUTH_DISABLED );
}
@Override
public Transaction beginTx( long timeout, TimeUnit unit )
{
return beginTransaction( KernelTransaction.Type.explicit, AUTH_DISABLED, timeout, unit );
}
@Override
public InternalTransaction beginTransaction( KernelTransaction.Type type, SecurityContext securityContext )
{
return beginTransactionInternal( type, securityContext, config.get( transaction_timeout ).toMillis() );
}
@Override
public InternalTransaction beginTransaction( KernelTransaction.Type type, SecurityContext securityContext,
long timeout, TimeUnit unit )
{
return beginTransactionInternal( type, securityContext, unit.toMillis( timeout ) );
}
@Override
public Result execute( String query ) throws QueryExecutionException
{
return execute( query, Collections.emptyMap() );
}
@Override
public Result execute( String query, long timeout, TimeUnit unit ) throws QueryExecutionException
{
return execute( query, Collections.emptyMap(), timeout, unit );
}
@Override
public Result execute( String query, Map<String,Object> parameters ) throws QueryExecutionException
{
// ensure we have a tx and create a context (the tx is gonna get closed by the Cypher result)
InternalTransaction transaction =
beginTransaction( KernelTransaction.Type.implicit, AUTH_DISABLED );
return execute( transaction, query, ValueUtils.asMapValue( parameters ) );
}
@Override
public Result execute( String query, Map<String,Object> parameters, long timeout, TimeUnit unit ) throws
QueryExecutionException
{
InternalTransaction transaction =
beginTransaction( KernelTransaction.Type.implicit, AUTH_DISABLED, timeout, unit );
return execute( transaction, query, ValueUtils.asMapValue( parameters ) );
}
public Result execute( InternalTransaction transaction, String query, MapValue parameters )
throws QueryExecutionException
{
TransactionalContext context =
contextFactory.newContext( ClientConnectionInfo.EMBEDDED_CONNECTION, transaction, query, parameters );
return spi.executeQuery( query, parameters, context );
}
@Override
public ResourceIterable<Node> getAllNodes()
{
KernelTransaction ktx = spi.currentTransaction();
assertTransactionOpen( ktx );
return () ->
{
Statement statement = ktx.acquireStatement();
NodeCursor cursor = ktx.cursors().allocateNodeCursor();
ktx.dataRead().allNodesScan( cursor );
return new PrefetchingResourceIterator<Node>()
{
@Override
protected Node fetchNextOrNull()
{
if ( cursor.next() )
{
return new NodeProxy( nodeActions, cursor.nodeReference() );
}
else
{
close();
return null;
}
}
@Override
public void close()
{
cursor.close();
statement.close();
}
};
};
}
@Override
public ResourceIterable<Relationship> getAllRelationships()
{
assertTransactionOpen();
return () ->
{
final Statement statement = spi.currentStatement();
final PrimitiveLongIterator ids = statement.readOperations().relationshipsGetAll();
return new PrefetchingResourceIterator<Relationship>()
{
@Override
public void close()
{
statement.close();
}
@Override
protected Relationship fetchNextOrNull()
{
if ( ids.hasNext() )
{
return new RelationshipProxy( relActions, ids.next() );
}
else
{
close();
return null;
}
}
};
};
}
@Override
public ResourceIterable<Label> getAllLabelsInUse()
{
return allInUse( TokenAccess.LABELS );
}
@Override
public ResourceIterable<RelationshipType> getAllRelationshipTypesInUse()
{
return allInUse( TokenAccess.RELATIONSHIP_TYPES );
}
private <T> ResourceIterable<T> allInUse( final TokenAccess<T> tokens )
{
assertTransactionOpen();
return () -> tokens.inUse( spi.currentStatement() );
}
@Override
public ResourceIterable<Label> getAllLabels()
{
return all( TokenAccess.LABELS );
}
@Override
public ResourceIterable<RelationshipType> getAllRelationshipTypes()
{
return all( TokenAccess.RELATIONSHIP_TYPES );
}
@Override
public ResourceIterable<String> getAllPropertyKeys()
{
return all( TokenAccess.PROPERTY_KEYS );
}
private <T> ResourceIterable<T> all( final TokenAccess<T> tokens )
{
assertTransactionOpen();
return () -> tokens.all( spi.currentStatement() );
}
@Override
public KernelEventHandler registerKernelEventHandler(
KernelEventHandler handler )
{
spi.registerKernelEventHandler( handler );
return handler;
}
@Override
public <T> TransactionEventHandler<T> registerTransactionEventHandler(
TransactionEventHandler<T> handler )
{
spi.registerTransactionEventHandler( handler );
return handler;
}
@Override
public KernelEventHandler unregisterKernelEventHandler(
KernelEventHandler handler )
{
spi.unregisterKernelEventHandler( handler );
return handler;
}
@Override
public <T> TransactionEventHandler<T> unregisterTransactionEventHandler(
TransactionEventHandler<T> handler )
{
spi.unregisterTransactionEventHandler( handler );
return handler;
}
@Override
public ResourceIterator<Node> findNodes( final Label myLabel, final String key, final Object value )
{
return nodesByLabelAndProperty( myLabel, key, Values.of( value ) );
}
@Override
public Node findNode( final Label myLabel, final String key, final Object value )
{
try ( ResourceIterator<Node> iterator = findNodes( myLabel, key, value ) )
{
if ( !iterator.hasNext() )
{
return null;
}
Node node = iterator.next();
if ( iterator.hasNext() )
{
throw new MultipleFoundException(
format( "Found multiple nodes with label: '%s', property name: '%s' and property " +
"value: '%s' while only one was expected.", myLabel, key, value ) );
}
return node;
}
}
@Override
public ResourceIterator<Node> findNodes( final Label myLabel )
{
return allNodesWithLabel( myLabel );
}
private InternalTransaction beginTransactionInternal( KernelTransaction.Type type, SecurityContext securityContext,
long timeoutMillis )
{
if ( spi.isInOpenTransaction() )
{
// FIXME: perhaps we should check that the new type and access mode are compatible with the current tx
return new PlaceboTransaction( spi::currentTransaction, spi::currentStatement );
}
return new TopLevelTransaction( spi.beginTransaction( type, securityContext, timeoutMillis ),
spi::currentStatement );
}
private ResourceIterator<Node> nodesByLabelAndProperty( Label myLabel, String key, Value value )
{
Statement statement = spi.currentStatement();
ReadOperations readOps = statement.readOperations();
int propertyId = readOps.propertyKeyGetForName( key );
int labelId = readOps.labelGetForName( myLabel.name() );
if ( propertyId == NO_SUCH_PROPERTY_KEY || labelId == NO_SUCH_LABEL )
{
statement.close();
return emptyResourceIterator();
}
IndexDescriptor descriptor = findAnyIndexByLabelAndProperty( readOps, propertyId, labelId );
try
{
if ( null != descriptor )
{
// Ha! We found an index - let's use it to find matching nodes
IndexQuery.ExactPredicate query = IndexQuery.exact( descriptor.schema().getPropertyId(), value );
PrimitiveLongResourceIterator indexResult = readOps.indexQuery( descriptor, query );
return map2nodes( indexResult, statement, indexResult );
}
}
catch ( KernelException e )
{
// weird at this point but ignore and fallback to a label scan
}
return getNodesByLabelAndPropertyWithoutIndex( propertyId, value, statement, labelId );
}
private IndexDescriptor findAnyIndexByLabelAndProperty( ReadOperations readOps, int propertyId, int labelId )
{
try
{
IndexDescriptor descriptor =
readOps.indexGetForSchema( SchemaDescriptorFactory.forLabel( labelId, propertyId ) );
if ( readOps.indexGetState( descriptor ) == InternalIndexState.ONLINE )
{
// Ha! We found an index - let's use it to find matching nodes
return descriptor;
}
}
catch ( SchemaRuleNotFoundException | IndexNotFoundKernelException e )
{
// If we don't find a matching index rule, we'll scan all nodes and filter manually (below)
}
return null;
}
private ResourceIterator<Node> getNodesByLabelAndPropertyWithoutIndex( int propertyId, Value value,
Statement statement, int labelId )
{
PrimitiveLongResourceIterator nodeIds = statement.readOperations().nodesGetForLabel( labelId );
return map2nodes( new PropertyValueFilteringNodeIdIterator( nodeIds, statement.readOperations(), propertyId, value ),
statement, nodeIds );
}
private ResourceIterator<Node> allNodesWithLabel( final Label myLabel )
{
KernelTransaction ktx = spi.currentTransaction();
assertTransactionOpen( ktx );
int labelId = ktx.tokenRead().labelGetForName( myLabel.name() );
if ( labelId == NO_SUCH_LABEL )
{
return ResourceIterator.empty();
}
NodeLabelIndexCursor cursor = ktx.cursors().allocateNodeLabelIndexCursor();
ktx.dataRead().nodeLabelScan( labelId, cursor );
return new PrefetchingResourceIterator<Node>()
{
@Override
protected Node fetchNextOrNull()
{
if ( cursor.next() )
{
return new NodeProxy( nodeActions, cursor.nodeReference() );
}
else
{
close();
return null;
}
}
@Override
public void close()
{
cursor.close();
}
};
}
private ResourceIterator<Node> map2nodes( PrimitiveLongIterator input, Resource... resources )
{
return new ResourceIterator<Node>()
{
private boolean closed;
@Override
public void close()
{
if ( !closed && resources != null )
{
ResourceUtils.closeAll( resources );
closed = true;
}
}
@Override
public boolean hasNext()
{
boolean hasNext = input.hasNext();
if ( !hasNext )
{
close();
}
return hasNext;
}
@Override
public Node next()
{
try
{
return new NodeProxy( nodeActions, input.next() );
}
catch ( NoSuchElementException e )
{
close();
throw e;
}
}
};
}
@Override
public TraversalDescription traversalDescription()
{
return new MonoDirectionalTraversalDescription( spi::currentStatement );
}
@Override
public BidirectionalTraversalDescription bidirectionalTraversalDescription()
{
return new BidirectionalTraversalDescriptionImpl( spi::currentStatement );
}
// GraphDatabaseAPI
@Override
public DependencyResolver getDependencyResolver()
{
return spi.resolver();
}
@Override
public StoreId storeId()
{
return spi.storeId();
}
@Override
public URL validateURLAccess( URL url ) throws URLAccessValidationError
{
return spi.validateURLAccess( url );
}
@Override
public File getStoreDir()
{
return spi.storeDir();
}
@Override
public String toString()
{
return spi.name() + " [" + getStoreDir() + "]";
}
private static class PropertyValueFilteringNodeIdIterator extends PrimitiveLongCollections.PrimitiveLongBaseIterator
{
private final PrimitiveLongIterator nodesWithLabel;
private final ReadOperations statement;
private final int propertyKeyId;
private final Value value;
PropertyValueFilteringNodeIdIterator( PrimitiveLongIterator nodesWithLabel, ReadOperations statement,
int propertyKeyId, Value value )
{
this.nodesWithLabel = nodesWithLabel;
this.statement = statement;
this.propertyKeyId = propertyKeyId;
this.value = value;
}
@Override
protected boolean fetchNext()
{
for ( boolean hasNext = nodesWithLabel.hasNext(); hasNext; hasNext = nodesWithLabel.hasNext() )
{
long nextValue = nodesWithLabel.next();
try
{
Value propertyValue = statement.nodeGetProperty( nextValue, propertyKeyId );
if ( propertyValue != null )
{
if ( propertyValue.equals( value ) )
{
return next( nextValue );
}
}
}
catch ( EntityNotFoundException e )
{
// continue to the next node
}
}
return false;
}
}
private void assertTransactionOpen()
{
assertTransactionOpen( spi.currentTransaction() );
}
private void assertTransactionOpen( KernelTransaction transaction )
{
if ( transaction.isTerminated() )
{
Status terminationReason = transaction.getReasonIfTerminated().orElse( Status.Transaction.Terminated );
throw new TransactionTerminatedException( terminationReason );
}
}
}