/**
* File ./src/main/java/de/lemo/dms/service/ServiceCourseDetails.java
* Lemo-Data-Management-Server for learning analytics.
* Copyright (C) 2013
* Leonard Kappe, Andreas Pursian, Sebastian Schwarzrock, Boris Wenzlaff
*
* This program 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
* any later version.
*
* This program 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 this program. If not, see <http://www.gnu.org/licenses/>.
**/
/**
* File ./main/java/de/lemo/dms/service/ServiceCourseDetails.java
* Date 2013-01-24
* Project Lemo Learning Analytics
*/
package de.lemo.dms.service;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Map;
import javax.ws.rs.GET;
import javax.ws.rs.Path;
import javax.ws.rs.PathParam;
import javax.ws.rs.Produces;
import javax.ws.rs.QueryParam;
import javax.ws.rs.core.MediaType;
import org.hibernate.Criteria;
import org.hibernate.Session;
import org.hibernate.criterion.Restrictions;
import org.apache.log4j.Logger;
import de.lemo.dms.core.config.ServerConfiguration;
import de.lemo.dms.db.IDBHandler;
import de.lemo.dms.db.mapping.CourseMining;
import de.lemo.dms.db.mapping.abstractions.ICourseLORelation;
import de.lemo.dms.db.mapping.abstractions.ILogMining;
import de.lemo.dms.processing.MetaParam;
import de.lemo.dms.processing.StudentHelper;
import de.lemo.dms.processing.resulttype.CourseObject;
import de.lemo.dms.processing.resulttype.ResultListCourseObject;
import de.lemo.dms.service.responses.ResourceNotFoundException;
/**
* Service to get details for a single course or a list of courses.
*
* @author Boris Wenzlaff
* @author Leonard Kappe
* @author Sebastian Schwarzrock
*/
@Path("courses")
@Produces(MediaType.APPLICATION_JSON)
public class ServiceCourseDetails {
private Logger logger = Logger.getLogger(this.getClass());
/**
* Gets the details for a single course including id, title, description,
* number of participants, time of first student-request, time of latest student-request.
*
* @param id Identifier of the course.
*
* @return A CourseObject containing the information.
*/
@SuppressWarnings("unchecked")
@GET
@Path("{cid}")
public CourseObject getCourseDetails(@PathParam("cid") final Long id) {
IDBHandler dbHandler = ServerConfiguration.getInstance().getMiningDbHandler();
final Session session = dbHandler.getMiningSession();
CourseMining course = (CourseMining) session.get(CourseMining.class, id);
if (course == null) {
throw new ResourceNotFoundException("Course " + id);
}
final Criteria criteria = session.createCriteria(ILogMining.class, "log");
List<Long> cid = new ArrayList<Long>();
cid.add(id);
List<Long> users = new ArrayList<Long>(StudentHelper.getCourseStudentsAliasKeys(cid, new ArrayList<Long>()).values());
criteria.add(Restrictions.eq("log.course.id", id));
if(users.size() > 0)
{
criteria.add(Restrictions.in("log.user.id", users));
}
ArrayList<ILogMining> logs = (ArrayList<ILogMining>) criteria.list();
Collections.sort(logs);
Long lastTime = 0L;
Long firstTime = 0L;
if (logs.size() > 0)
{
lastTime = logs.get(logs.size() - 1).getTimestamp();
firstTime = logs.get(0).getTimestamp();
}
CourseObject result =
new CourseObject(course.getId(), course.getShortname(), course.getTitle(), users.size(), lastTime, firstTime, getCourseHash(id), StudentHelper.getGenderSupport(id));
//dbHandler.closeSession(session);
session.close();
return result;
}
/**
* Gets the details for a a list of courses including id, title, description,
* number of participants, time of first student-request, time of latest student-request.
*
* @param id List of course identifiers.
*
* @return A List of CourseObjects containing the information.
*/
@SuppressWarnings("unchecked")
@GET
@Path("/multi")
public ResultListCourseObject getCoursesDetails(@QueryParam(MetaParam.COURSE_IDS) final List<Long> courses) {
IDBHandler dbHandler = ServerConfiguration.getInstance().getMiningDbHandler();
final ArrayList<CourseObject> results = new ArrayList<CourseObject>();
if (courses.isEmpty()) {
logger.debug("Courses List is empty");
return new ResultListCourseObject(results);
} else for(Long id : courses) logger.debug("Looking for Course: "+ id);
// Set up db-connection
final Session session = dbHandler.getMiningSession();
Criteria criteria = session.createCriteria(CourseMining.class, "course");
criteria.add(Restrictions.in("course.id", courses));
final ArrayList<CourseMining> ci = (ArrayList<CourseMining>) criteria.list();
Map<Long, Long> userMap = StudentHelper.getCourseStudentsAliasKeys(courses, new ArrayList<Long>());
for (CourseMining courseMining : ci) {
criteria = session.createCriteria(ILogMining.class, "log");
criteria.add(Restrictions.eq("log.course.id", courseMining.getId()));
if(userMap.size() > 0)
{
criteria.add(Restrictions.in("log.user.id", userMap.values()));
}
//TODO Redefine projection for max id as detachable criteria (Subselect)
//DetachedCriteria sub = DetachedCriteria.forClass(ILogMining.class);
// sub.setProjection(Projections.max("id"));
//
//criteria.add(Restrictions.eq("id",sub));
ArrayList<ILogMining> logs = (ArrayList<ILogMining>) criteria.list();
Collections.sort(logs);
Long lastTime = 0L;
Long firstTime = 0L;
if (logs.size() > 0)
{
lastTime = logs.get(0).getTimestamp();
firstTime = logs.get(logs.size() - 1).getTimestamp();
}
final CourseObject co = new CourseObject(courseMining.getId(), courseMining.getShortname(),
courseMining.getTitle(), userMap.size(), lastTime, firstTime, getCourseHash(courseMining.getId()), StudentHelper.getGenderSupport(courseMining.getId()));
results.add(co);
}
if (results.isEmpty()) {
logger.debug("Result List is empty");
} else for(CourseObject co : results) logger.debug("Result Course: "+ co.getDescription());
session.close();
return new ResultListCourseObject(results);
}
/**
* Gets the details for a a list of courses including id, title, description,
* number of participants, time of first student-request, time of latest student-request.
*
* @param id List of course identifiers.
*
* @return A List of CourseObjects containing the information.
*/
@SuppressWarnings("unchecked")
@GET
@Path("{cid}/hash")
public Long getCourseHash(@PathParam("cid") final Long id) {
IDBHandler dbHandler = ServerConfiguration.getInstance().getMiningDbHandler();
final Session session = dbHandler.getMiningSession();
CourseMining course = (CourseMining) session.get(CourseMining.class, id);
if (course == null) {
throw new ResourceNotFoundException("Course " + id);
}
Criteria criteria = session.createCriteria(ILogMining.class, "log");
List<Long> cid = new ArrayList<Long>();
cid.add(id);
List<Long> users = new ArrayList<Long>(StudentHelper.getCourseStudentsRealKeys(cid, new ArrayList<Long>()).values());
criteria.add(Restrictions.eq("log.course.id", id));
if(users.size() > 0)
{
criteria.add(Restrictions.in("log.user.id", users));
}
ArrayList<ILogMining> logs = (ArrayList<ILogMining>) criteria.list();
Collections.sort(logs);
Long lastTime = 0L;
Long firstTime = 0L;
if (logs.size() > 0)
{
lastTime = logs.get(logs.size() - 1).getTimestamp();
firstTime = logs.get(0).getTimestamp();
}
criteria = session.createCriteria(ICourseLORelation.class, "lor");
criteria.add(Restrictions.eq("lor.course.id", id));
ArrayList<ICourseLORelation> lor = (ArrayList<ICourseLORelation>) criteria.list();
Long hash = lastTime * 13 + firstTime * 17 + 19 * users.hashCode() + 23 * lor.hashCode();
//dbHandler.closeSession(session);
session.close();
return hash;
}
/**
* Gets the details for a a list of courses including id, title, description,
* number of participants, time of first student-request, time of latest student-request.
*
* @param id List of course identifiers.
*
* @return A List of CourseObjects containing the information.
*/
@GET
@Path("{cid}/genderSupport")
public boolean getGenderSupport(@PathParam("cid") final Long id) {
return StudentHelper.getGenderSupport(id);
}
}