Java tutorial
/** * File ./src/main/java/de/lemo/dms/processing/questions/QCumulativeUserAccess.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/processing/questions/QCumulativeUserAccess.java * Date 2013-01-24 * Project Lemo Learning Analytics */ package de.lemo.dms.processing.questions; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; import java.util.Set; import javax.ws.rs.FormParam; import javax.ws.rs.POST; import javax.ws.rs.Path; import org.hibernate.Criteria; import org.hibernate.Session; import org.hibernate.criterion.Restrictions; import de.lemo.dms.core.config.ServerConfiguration; import de.lemo.dms.db.mapping.abstractions.ILogMining; import de.lemo.dms.processing.BoxPlotGeneratorForDates; import de.lemo.dms.processing.ELearningObjectType; import de.lemo.dms.processing.MetaParam; import de.lemo.dms.processing.Question; import de.lemo.dms.processing.resulttype.BoxPlot; import de.lemo.dms.processing.resulttype.ResultListBoxPlot; /** * Accumulates the requests of the users to the objects over a period * * @author Boris Wenzlaff * @author Sebastian Schwarzrock */ @Path("cumulative") public class QCumulativeUserAccess extends Question { /** * @param startTime * min time for the data * @param endTime * max time for the data * @param types * list with learning objects to compute * @param course * courses for the request * @return a list with the cumulative user access to the learning objects * @throws SQLException * @throws JSONException */ @SuppressWarnings("unchecked") @POST public ResultListBoxPlot compute(@FormParam(MetaParam.COURSE_IDS) final List<Long> course, @FormParam(MetaParam.TYPES) List<String> types, @FormParam(MetaParam.START_TIME) final Long startTime, @FormParam(MetaParam.END_TIME) final Long endTime) { validateTimestamps(startTime, endTime); final Set<ELearningObjectType> learnObjectTypes = ELearningObjectType.fromNames(types); if (types != null) { List<String> tmp = new ArrayList<String>(); for (String s : types) { tmp.add(s.toUpperCase()); } types = tmp; } // generiere querys final Map<ELearningObjectType, String> querys = this.generateQuerys(startTime, endTime, learnObjectTypes, course); super.logger.debug("Query result: " + querys.toString()); final Session session = ServerConfiguration.getInstance().getMiningDbHandler().getMiningSession(); // SQL querys super.logger.debug("Starting processing ...."); final BoxPlotGeneratorForDates bpg = new BoxPlotGeneratorForDates(); try { Criteria criteria = session.createCriteria(ILogMining.class, "log"); criteria.add(Restrictions.between("log.timestamp", startTime, endTime)); criteria.add(Restrictions.in("log.course.id", course)); List<ILogMining> logs = criteria.list(); for (ILogMining log : logs) { String type = log.getClass().getSimpleName().toUpperCase(); if (type.indexOf("LOG") > -1) { type = type.substring(0, type.indexOf("LOG")); if (types.isEmpty() || types.contains(type)) bpg.addAccess(log.getTimestamp()); } } logs.clear(); /* for (final ELearningObjectType lo : querys.keySet()) { super.logger.debug("Starting processing -- Entering try catch"); @SuppressWarnings("deprecation") final Statement statement = session.connection().createStatement(); final ResultSet set = statement.executeQuery(querys.get(lo)); // durchlaufen des result sets while (set.next()) { bpg.addAccess(set.getLong("timestamp")); } } */ final BoxPlot[] bp = bpg.calculateResult(); final List<BoxPlot> l = new ArrayList<BoxPlot>(); for (int i = 0; i < bp.length; i++) { l.add(bp[i]); } final ResultListBoxPlot rlbp = new ResultListBoxPlot(l); super.logger.debug("Resultlist created ...." + rlbp.toString() + " Number of entries: " + rlbp.getElements().size()); session.close(); return rlbp; } catch (final Exception e) { this.logger.error(e); session.close(); return new ResultListBoxPlot(); } } /** * Generiert die Querys fr die Zusammenfassung der LearningObjects * Insbesondere der WHERE Klausel * * @param timestampMin * Untergrenze fr den Zeitraum * @param timestampMax * Obergrenze fr den Zeitraum * @param types * Learning Objects die erfasst werden sollen * @return Liste mit Querys zu den LearningObjects */ private Map<ELearningObjectType, String> generateQuerys(final long timestampMin, final long timestampMax, final Set<ELearningObjectType> types, final List<Long> course) { final Map<ELearningObjectType, String> result = new HashMap<ELearningObjectType, String>(); boolean timeframe = false; final List<String> qa = new ArrayList<String>(); // prfen des zeitraums if ((timestampMax != 0) && (timestampMin != 0) && (timestampMax >= timestampMin)) { timeframe = true; } for (final ELearningObjectType loType : types) { String query = this.generateBaseQuery(loType.name().toLowerCase()); if (timeframe || (course != null)) { query += " WHERE"; } // zeitraum if (timeframe) { qa.add(" timestamp >= " + timestampMin + " AND timestamp<= " + timestampMax); } // filter course if ((course != null) && !course.isEmpty()) { final StringBuilder sb = new StringBuilder(); sb.append("("); int i = 0; for (final Long co : course) { sb.append(" course.id = " + co.toString()); if (i < (course.size() - 1)) { sb.append(" OR"); } i++; } sb.append(")"); qa.add(sb.toString()); } // klauseln fr filter hinzufgen for (int i = 0; i < qa.size(); i++) { query += qa.get(i); if (i < (qa.size() - 1)) { query += " AND"; } } result.put(loType, query); } return result; } // generiert ein einfaches query mit einem inner join fr die abfrage private String generateBaseQuery(final String table) { final StringBuilder sb = new StringBuilder(); sb.append("SELECT timestamp, user_id, course.title as course, course.id as courseId"); sb.append(" FROM " + table + "_log AS log"); sb.append(" LEFT JOIN course"); sb.append(" ON course.id = log.course_id"); return sb.toString(); } }