org.dswarm.graph.utils.GraphDatabaseUtils.java Source code

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Here is the source code for org.dswarm.graph.utils.GraphDatabaseUtils.java

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/**
 * 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.utils;

import java.io.File;
import java.io.IOException;
import java.net.URL;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.Properties;

import javax.management.ObjectName;

import com.google.common.io.Resources;
import org.neo4j.graphdb.GraphDatabaseService;
import org.neo4j.jmx.JmxUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import org.dswarm.graph.index.MapDBUtils;

/**
 * @author tgaengler
 */
public final class GraphDatabaseUtils {

    private static final Logger LOG = LoggerFactory.getLogger(GraphDatabaseUtils.class);
    private static final String KERNEL = "Kernel";
    private static final String STORE_DIR = "StoreDirectory";

    public static String determineMapDBIndexStoreDir(final GraphDatabaseService database) {

        final URL resource = Resources.getResource("dmpgraph.properties");
        final Properties properties = new Properties();

        try {

            properties.load(resource.openStream());
        } catch (final IOException e) {

            LOG.error("Could not load dmpgraph.properties", e);
        }

        final String indexStoreDir = properties.getProperty("index_store_dir");

        // TODO: find a better way to determine the store dir for the statement index
        String storeDir = null;

        if (indexStoreDir != null && !indexStoreDir.trim().isEmpty()) {

            storeDir = indexStoreDir;
        } else if (getGraphDatabaseStoreDir(database) != null) {

            final String databaseStoreDir = getGraphDatabaseStoreDir(database);

            if (databaseStoreDir != null) {

                final Path databaseStoreDirPath = Paths.get(databaseStoreDir);

                if (databaseStoreDirPath != null) {

                    if (Files.exists(databaseStoreDirPath)) {

                        final String newIndexStoreDir = databaseStoreDir + File.separator + MapDBUtils.INDEX_DIR;

                        final Path newIndexStoreDirPath = Paths.get(newIndexStoreDir);

                        if (Files.notExists(newIndexStoreDirPath)) {

                            try {

                                Files.createDirectory(newIndexStoreDirPath);

                                storeDir = newIndexStoreDir;
                            } catch (final IOException e) {

                                LOG.debug("couldn't create map db index directory");
                            }
                        } else {

                            storeDir = newIndexStoreDir;
                        }
                    }
                }
            }
        }

        if (storeDir == null) {

            // fallback default
            storeDir = System.getProperty("user.dir") + "/target";

            LOG.debug("utilise fallback default for mapdb index store dir");
        }

        LOG.debug("mapdb index store dir '{}'", storeDir);

        return storeDir;
    }

    public static String getGraphDatabaseStoreDir(final GraphDatabaseService graphDbService) {

        final ObjectName objectName = JmxUtils.getObjectName(graphDbService, KERNEL);
        return JmxUtils.getAttribute(objectName, STORE_DIR);
    }
}