package com.buschmais.cdo.neo4j.impl.datastore;
import com.buschmais.cdo.api.CdoException;
import com.buschmais.cdo.api.ResultIterator;
import com.buschmais.cdo.neo4j.api.Neo4jDatastoreSession;
import com.buschmais.cdo.neo4j.api.annotation.Cypher;
import com.buschmais.cdo.neo4j.impl.datastore.metadata.Neo4jRelationshipType;
import com.buschmais.cdo.neo4j.impl.datastore.metadata.NodeMetadata;
import com.buschmais.cdo.neo4j.impl.datastore.metadata.PropertyMetadata;
import com.buschmais.cdo.spi.datastore.DatastorePropertyManager;
import com.buschmais.cdo.spi.datastore.TypeMetadataSet;
import com.buschmais.cdo.spi.metadata.method.IndexedPropertyMethodMetadata;
import com.buschmais.cdo.spi.metadata.method.PrimitivePropertyMethodMetadata;
import com.buschmais.cdo.spi.metadata.type.EntityTypeMetadata;
import org.neo4j.graphdb.*;
import java.lang.reflect.AnnotatedElement;
import java.util.HashSet;
import java.util.Set;
/**
* Abstract base implementation of a Neo4j database session based on the {@link org.neo4j.graphdb.GraphDatabaseService} API.
*
* @param <GDS> The type of {@link org.neo4j.graphdb.GraphDatabaseService}.
*/
public abstract class AbstractNeo4jDatastoreSession<GDS extends GraphDatabaseService> implements Neo4jDatastoreSession<GDS> {
private final GDS graphDatabaseService;
private final Neo4jPropertyManager propertyManager;
public AbstractNeo4jDatastoreSession(GDS graphDatabaseService) {
this.graphDatabaseService = graphDatabaseService;
this.propertyManager = new Neo4jPropertyManager();
}
@Override
public DatastorePropertyManager getDatastorePropertyManager() {
return propertyManager;
}
@Override
public GDS getGraphDatabaseService() {
return graphDatabaseService;
}
@Override
public Node createEntity(TypeMetadataSet<EntityTypeMetadata<NodeMetadata>> types, Set<Label> discriminators) {
Node node = getGraphDatabaseService().createNode();
for (Label label : discriminators) {
node.addLabel(label);
}
return node;
}
@Override
public ResultIterator<Node> findEntity(EntityTypeMetadata<NodeMetadata> entityTypeMetadata, Label discriminator, Object value) {
IndexedPropertyMethodMetadata<?> indexedProperty = entityTypeMetadata.getDatastoreMetadata().getIndexedProperty();
if (indexedProperty == null) {
indexedProperty = entityTypeMetadata.getIndexedProperty();
}
if (indexedProperty == null) {
throw new CdoException("Type " + entityTypeMetadata.getAnnotatedType().getAnnotatedElement().getName() + " has no indexed property.");
}
PrimitivePropertyMethodMetadata<PropertyMetadata> propertyMethodMetadata = indexedProperty.getPropertyMethodMetadata();
ResourceIterable<Node> nodesByLabelAndProperty = getGraphDatabaseService().findNodesByLabelAndProperty(discriminator, propertyMethodMetadata.getDatastoreMetadata().getName(), value);
ResourceIterator<Node> iterator = nodesByLabelAndProperty.iterator();
return new ResourceResultIterator(iterator);
}
@Override
public void migrateEntity(Node entity, TypeMetadataSet<EntityTypeMetadata<NodeMetadata>> types, Set<Label> discriminators, TypeMetadataSet<EntityTypeMetadata<NodeMetadata>> targetTypes, Set<Label> targetDiscriminators) {
Set<Label> labelsToRemove = new HashSet<>(discriminators);
labelsToRemove.removeAll(targetDiscriminators);
for (Label label : labelsToRemove) {
entity.removeLabel(label);
}
Set<Label> labelsToAdd = new HashSet<>(targetDiscriminators);
labelsToAdd.removeAll(discriminators);
for (Label label : labelsToAdd) {
entity.addLabel(label);
}
}
@Override
public boolean isEntity(Object o) {
return Node.class.isAssignableFrom(o.getClass());
}
@Override
public boolean isRelation(Object o) {
return Relationship.class.isAssignableFrom(o.getClass());
}
@Override
public Long getEntityId(Node entity) {
return Long.valueOf(entity.getId());
}
@Override
public void deleteEntity(Node entity) {
entity.delete();
}
@Override
public void flushEntity(Node node) {
}
protected <QL> String getCypher(QL expression) {
if (expression instanceof String) {
return (String) expression;
} else if (expression instanceof AnnotatedElement) {
AnnotatedElement typeExpression = (AnnotatedElement) expression;
Cypher cypher = typeExpression.getAnnotation(Cypher.class);
if (cypher == null) {
throw new CdoException(typeExpression + " must be annotated with " + Cypher.class.getName());
}
return cypher.value();
}
throw new CdoException("Unsupported query expression " + expression);
}
@Override
public Set<Label> getEntityDiscriminators(Node node) {
Set<Label> labels = new HashSet<>();
for (Label label : node.getLabels()) {
labels.add(label);
}
return labels;
}
@Override
public Long getRelationId(Relationship relationship) {
return relationship.getId();
}
@Override
public Neo4jRelationshipType getRelationDiscriminator(Relationship relationship) {
return new Neo4jRelationshipType(relationship.getType());
}
@Override
public void flushRelation(Relationship relationship) {
}
}