PropertyGraphGDMResourceByIDReader.java

/**
 * This file is part of d:swarm graph extension.
 *
 * d:swarm graph extension 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.
 *
 * d:swarm graph extension 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 d:swarm graph extension.  If not, see <http://www.gnu.org/licenses/>.
 */
package org.dswarm.graph.gdm.read;

import java.util.Optional;

import org.neo4j.graphdb.GraphDatabaseService;
import org.neo4j.graphdb.Node;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import org.dswarm.common.model.AttributePath;
import org.dswarm.graph.DMPGraphException;
import org.dswarm.graph.delta.util.GraphDBUtil;
import org.dswarm.graph.index.NamespaceIndex;
import org.dswarm.graph.tx.TransactionHandler;

/**
 * @author tgaengler
 */
public class PropertyGraphGDMResourceByIDReader extends PropertyGraphGDMResourceReader {

	private static final Logger LOG = LoggerFactory.getLogger(PropertyGraphGDMResourceByIDReader.class);

	private static final String TYPE = "GDM record by ID";

	private final String recordId;
	private String prefixedRecordURI;
	private final AttributePath prefixedRecordIdentifierAP;

	public PropertyGraphGDMResourceByIDReader(final String recordIdArg, final AttributePath prefixedRecordIdentifierAPArg,
	                                          final String prefixedDataModelUri,
	                                          final Optional<Integer> optionalVersionArg,
	                                          final GraphDatabaseService database, final TransactionHandler tx, final NamespaceIndex namespaceIndex) throws DMPGraphException {

		super(prefixedDataModelUri, optionalVersionArg, database, tx, namespaceIndex, TYPE);

		recordId = recordIdArg;
		prefixedRecordIdentifierAP = prefixedRecordIdentifierAPArg;
		determineRecordUri();
	}

	@Override
	protected Node getResourceNode() throws DMPGraphException {

		if (prefixedRecordURI == null) {

			LOG.debug("couldn't a find a resource node to start traversal");

			return null;
		}

		final PropertyGraphGDMResourceByURIReader uriReader = new PropertyGraphGDMResourceByURIReader(prefixedRecordURI, prefixedDataModelUri,
				Optional.of(version),
				database, tx, namespaceIndex);

		return uriReader.getResourceNode();
	}

	private void determineRecordUri() throws DMPGraphException {

		prefixedRecordURI = GraphDBUtil.determineRecordUri(recordId, prefixedRecordIdentifierAP, prefixedDataModelUri, database);
	}
}