/**
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.marmotta.ldpath.backend.linkeddata;
import org.apache.marmotta.commons.sesame.filter.AlwaysTrueFilter;
import org.apache.marmotta.commons.sesame.filter.SesameFilter;
import org.apache.marmotta.ldcache.backend.file.LDCachingFileBackend;
import org.apache.marmotta.ldcache.sail.GenericLinkedDataSail;
import org.apache.marmotta.ldclient.model.ClientConfiguration;
import org.apache.marmotta.ldpath.backend.sesame.SesameRepositoryBackend;
import org.openrdf.model.Resource;
import org.openrdf.repository.Repository;
import org.openrdf.repository.RepositoryException;
import org.openrdf.repository.sail.SailRepository;
import org.openrdf.sail.memory.MemoryStore;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.io.File;
import java.io.IOException;
/**
* A Linked Data backend with persistent caching of the retrieved data. All data is read and stored in the directory
* passed as constructor argument.
* <p/>
* Author: Sebastian Schaffert
*/
public class LDPersistentBackend extends SesameRepositoryBackend {
private static final Logger log = LoggerFactory.getLogger(LDPersistentBackend.class);
private LDCachingFileBackend backend;
private GenericLinkedDataSail sail;
private SesameFilter<Resource> cacheFilter;
/**
* Create a persistent linked data backend storing the cache data in the directory passed as argument.
* The directory will be created if it does not exist.
* @param dataDirectory
*/
public LDPersistentBackend(File dataDirectory) throws IOException {
super();
if(!dataDirectory.exists()) {
dataDirectory.mkdirs();
}
File tripleStore = new File(dataDirectory.getAbsolutePath()+File.separator+"triples");
if(!tripleStore.exists()) {
tripleStore.mkdirs();
}
cacheFilter = new AlwaysTrueFilter<Resource>();
try {
ClientConfiguration config = new ClientConfiguration();
backend = new LDCachingFileBackend(dataDirectory);
sail = new GenericLinkedDataSail(new MemoryStore(),backend, cacheFilter, config);
Repository repository = new SailRepository(sail);
repository.initialize();
setRepository(repository);
} catch (RepositoryException e) {
log.error("error initialising connection to Sesame in-memory repository",e);
}
}
public void shutdown() {
try {
getRepository().shutDown();
} catch (RepositoryException e) {
log.error("error shutting down repository for resource cache");
}
}
}