/*******************************************************************************
* Copyright 2012 University of Southern California
*
* Licensed 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.
*
* This code was developed by the Information Integration Group as part
* of the Karma project at the Information Sciences Institute of the
* University of Southern California. For more information, publications,
* and related projects, please see: http://www.isi.edu/integration
******************************************************************************/
package edu.isi.karma.model.serialization;
import java.io.File;
import java.io.FileInputStream;
import java.io.InputStream;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.hp.hpl.jena.query.Dataset;
import com.hp.hpl.jena.rdf.model.Model;
import com.hp.hpl.jena.rdf.model.ModelFactory;
import com.hp.hpl.jena.tdb.TDB;
import com.hp.hpl.jena.tdb.TDBFactory;
import com.hp.hpl.jena.tdb.base.file.Location;
import edu.isi.karma.webserver.ServletContextParameterMap;
import edu.isi.karma.webserver.ServletContextParameterMap.ContextParameter;
public class Repository {
public final String REPOSITORY_REL_DIR = "repository/";
public final String SERVICE_REPOSITORY_REL_DIR = "repository/services/";
public final String SOURCE_REPOSITORY_REL_DIR = "repository/sources/";
public final String TRIPLE_DATASET_REL_DIR = "repository/dataset/";
// @param LANG: The language in which to write the model is specified by the lang argument.
// * Predefined values are "RDF/XML", "RDF/XML-ABBREV", "N-TRIPLE", "TURTLE", (and "TTL") and "N3".
// * The default value, represented by null is "RDF/XML".
public final String LANG = SerializationLang.N3;
private static Logger logger = LoggerFactory.getLogger(Repository.class);
private Dataset dataset;
private static Repository _InternalInstance = null;
public static Repository Instance()
{
if (_InternalInstance == null)
{
_InternalInstance = new Repository();
File repository = new File(ServletContextParameterMap.getParameterValue(ContextParameter.USER_DIRECTORY_PATH) + _InternalInstance.REPOSITORY_REL_DIR);
if (!repository.exists())
repository.mkdir();
File tripleStore = new File(ServletContextParameterMap.getParameterValue(ContextParameter.USER_DIRECTORY_PATH) + _InternalInstance.TRIPLE_DATASET_REL_DIR);
if (!tripleStore.exists())
tripleStore.mkdir();
File serviceRepository = new File(ServletContextParameterMap.getParameterValue(ContextParameter.USER_DIRECTORY_PATH) + _InternalInstance.SERVICE_REPOSITORY_REL_DIR);
if (!serviceRepository.exists())
serviceRepository.mkdir();
File sourceRepository = new File(ServletContextParameterMap.getParameterValue(ContextParameter.USER_DIRECTORY_PATH) + _InternalInstance.SOURCE_REPOSITORY_REL_DIR);
if (!sourceRepository.exists())
sourceRepository.mkdir();
_InternalInstance.createRepository();
}
return _InternalInstance;
}
public void createRepository() {
Location location = new Location(ServletContextParameterMap.getParameterValue(ContextParameter.USER_DIRECTORY_PATH) + this.TRIPLE_DATASET_REL_DIR);
this.dataset = TDBFactory.createDataset(location);
// TDB.getContext().set(TDB.symUnionDefaultGraph, true);
}
public void addModel(Model m, String name) {
if (name == null) {
logger.info("cannot add the model because the given name is null.");
return;
}
Model namedModel = this.dataset.getNamedModel(name);
namedModel.removeAll();
namedModel.add(m.listStatements());
namedModel.setNsPrefixes(m.getNsPrefixMap());
namedModel.commit();
TDB.sync(this.dataset);
}
/**
* returns the union of all named models.
* @return
*/
public Model getModel() {
// 1) tdbDataset.getNamedModel("urn:x-arq:UnionGraph") does always return the union graph (even when
// TDB.getContext().set(TDB.symUnionDefaultGraph, true) is NOT set).
// 2) tdbDataset.getDefaultModel() does always return the 'real' default graph which is different/independent of (1).
// 3) so only in context of a SPARQL query the'default graph' contains the union of all named graphs.
return this.dataset.getNamedModel("urn:x-arq:UnionGraph") ;
}
public Model getNamedModel(String name) {
if (name == null) {
logger.info("cannot get the model because the given name is null.");
return null;
}
if (!this.dataset.containsNamedModel(name)) {
logger.info("The model: " + name + " does not exist in the repository.");
return null;
}
return this.dataset.getNamedModel(name);
}
public void clearNamedModel(String name) {
if (name == null) {
logger.info("cannot clear the model because the given name is null.");
return;
}
if (!this.dataset.containsNamedModel(name)) {
logger.info("The model " + name + " does not exist in the repository.");
return;
}
this.dataset.getNamedModel(name).removeAll();
this.dataset.getNamedModel(name).commit();
}
/**
* imports the named model from a directory or a file
* @param lang The language of the file specified by the lang argument.
* Predefined values are "RDF/XML", "RDF/XML-ABBREV", "N-TRIPLE", "TURTLE", (and "TTL") and "N3".
* The default value, represented by null is "RDF/XML".
* @param file
*/
public void importModel(File file, String lang) {
if (!file.exists()) {
logger.error("cannot find the file/dir at " + file.getAbsolutePath());
return;
}
if (file.isFile()) {
importModelFromSingleFile(file, lang);
} else if (file.isDirectory()) {
for (File f : file.listFiles()) {
importModelFromSingleFile(f, lang);
}
}
}
private void importModelFromSingleFile(File file, String lang) {
Model m = ModelFactory.createDefaultModel();
try {
InputStream s = new FileInputStream(file);
m.read(s, null);
this.addModel(m, file.getName());
logger.info("The model " + file.getPath() + " successfully imported to repository");
} catch (Throwable t) {
logger.error("Error reading the model file!", t);
return;
}
}
public String getFileExtension(String lang) {
String ext = ".rdf";
if (lang.equalsIgnoreCase("RDF/XML")) ext = ".rdf";
else if (lang.equalsIgnoreCase("RDF/XML-ABBREV")) ext = ".rdf";
else if (lang.equalsIgnoreCase("N-TRIPLE")) ext = ".ntriple";
else if (lang.equalsIgnoreCase("TURTLE")) ext = ".turtle";
else if (lang.equalsIgnoreCase("TTL")) ext = ".ttl";
else if (lang.equalsIgnoreCase("N3")) ext = ".n3";
return ext;
}
}