/**
* Copyright (C) 2010-2014 Morgner UG (haftungsbeschränkt)
*
* This file is part of Structr <http://structr.org>.
*
* Structr 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.
*
* Structr 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 Structr. If not, see <http://www.gnu.org/licenses/>.
*/
package org.structr.core.entity;
import org.neo4j.graphdb.Direction;
import static org.neo4j.graphdb.Direction.BOTH;
import static org.neo4j.graphdb.Direction.INCOMING;
import static org.neo4j.graphdb.Direction.OUTGOING;
import org.structr.common.SecurityContext;
import org.structr.common.error.FrameworkException;
import org.structr.core.app.App;
import org.structr.core.app.StructrApp;
import org.structr.core.graph.NodeInterface;
import org.structr.core.notion.Notion;
import org.structr.core.notion.RelationshipNotion;
/**
*
* @author Christian Morgner
*/
public abstract class ManyToOne<S extends NodeInterface, T extends NodeInterface> extends AbstractRelationship<S, T> implements Relation<S, T, ManyStartpoint<S>, OneEndpoint<T>> {
@Override
public Multiplicity getSourceMultiplicity() {
return Multiplicity.Many;
}
@Override
public Multiplicity getTargetMultiplicity() {
return Multiplicity.One;
}
@Override
public ManyStartpoint<S> getSource() {
return new ManyStartpoint<>(this);
}
@Override
public OneEndpoint<T> getTarget() {
return new OneEndpoint<>(this);
}
@Override
public int getCascadingDeleteFlag() {
return Relation.NONE;
}
@Override
public void ensureCardinality(final SecurityContext securityContext, final NodeInterface sourceNode, final NodeInterface targetNode) throws FrameworkException {
final App app = StructrApp.getInstance();
final Class<? extends ManyToOne> clazz = this.getClass();
final Class<T> targetType = getTargetType();
if (sourceNode != null) {
// check existing relationships
final Relation<?, T, ?, ?> outgoingRel = sourceNode.getOutgoingRelationship(clazz);
// if (outgoingRel != null && targetType.isAssignableFrom(outgoingRel.getTargetType())) {
if (outgoingRel != null && targetType.isInstance(outgoingRel.getTargetNode())) {
app.delete(outgoingRel);
}
}
}
@Override
public Notion getEndNodeNotion() {
return new RelationshipNotion(getTargetIdProperty());
}
@Override
public Notion getStartNodeNotion() {
return new RelationshipNotion(getSourceIdProperty());
}
@Override
public Direction getDirectionForType(final Class<? extends NodeInterface> type) {
return super.getDirectionForType(getSourceType(), getTargetType(), type);
}
@Override
public Class getOtherType(final Class type) {
switch (getDirectionForType(type)) {
case INCOMING: return getSourceType();
case OUTGOING: return getTargetType();
case BOTH: return getSourceType(); // don't know...
}
return null;
}
}