de.thm.arsnova.FeedbackStorage.java Source code

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Here is the source code for de.thm.arsnova.FeedbackStorage.java

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/*
 * This file is part of ARSnova Backend.
 * Copyright (C) 2012-2015 The ARSnova Team
 *
 * ARSnova Backend 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.
 *
 * ARSnova Backend 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/>.
 */
package de.thm.arsnova;

import java.util.ArrayList;
import java.util.Date;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.TimeUnit;

import org.springframework.transaction.annotation.Isolation;
import org.springframework.transaction.annotation.Transactional;

import de.thm.arsnova.entities.Feedback;
import de.thm.arsnova.entities.Session;
import de.thm.arsnova.entities.User;

public class FeedbackStorage {
    private static class FeedbackStorageObject {
        private final int value;
        private final Date timestamp;
        private final User user;

        public FeedbackStorageObject(final int initValue, final User u) {
            value = initValue;
            timestamp = new Date();
            user = u;
        }

        public int getValue() {
            return value;
        }

        public Date getTimestamp() {
            return timestamp;
        }

        public boolean fromUser(final User u) {
            return user.equals(u);
        }
    }

    private final Map<Session, Map<User, FeedbackStorageObject>> data = new ConcurrentHashMap<Session, Map<User, FeedbackStorageObject>>();

    public Feedback getFeedback(final Session session) {
        int a = 0;
        int b = 0;
        int c = 0;
        int d = 0;

        if (data.get(session) == null) {
            return new Feedback(0, 0, 0, 0);
        }

        for (final FeedbackStorageObject fso : data.get(session).values()) {
            switch (fso.getValue()) {
            case Feedback.FEEDBACK_FASTER:
                a++;
                break;
            case Feedback.FEEDBACK_OK:
                b++;
                break;
            case Feedback.FEEDBACK_SLOWER:
                c++;
                break;
            case Feedback.FEEDBACK_AWAY:
                d++;
                break;
            default:
                break;
            }
        }
        return new Feedback(a, b, c, d);
    }

    public Integer getMyFeedback(final Session session, final User u) {
        if (data.get(session) == null) {
            return null;
        }

        for (final FeedbackStorageObject fso : data.get(session).values()) {
            if (fso.fromUser(u)) {
                return fso.getValue();
            }
        }

        return null;
    }

    @Transactional(isolation = Isolation.READ_COMMITTED)
    public void saveFeedback(final Session session, final int value, final User user) {
        if (data.get(session) == null) {
            data.put(session, new ConcurrentHashMap<User, FeedbackStorageObject>());
        }

        data.get(session).put(user, new FeedbackStorageObject(value, user));
    }

    @Transactional(isolation = Isolation.READ_COMMITTED)
    public Map<Session, List<User>> cleanFeedbackVotes(final int cleanupFeedbackDelay) {
        final Map<Session, List<User>> removedFeedbackOfUsersInSession = new HashMap<Session, List<User>>();
        for (final Session session : data.keySet()) {
            List<User> affectedUsers = cleanFeedbackVotesInSession(session, cleanupFeedbackDelay);
            if (!affectedUsers.isEmpty()) {
                removedFeedbackOfUsersInSession.put(session, affectedUsers);
            }
        }
        return removedFeedbackOfUsersInSession;
    }

    private List<User> cleanFeedbackVotesInSession(final Session session, final int cleanupFeedbackDelayInMins) {
        final long timelimitInMillis = TimeUnit.MILLISECONDS.convert(cleanupFeedbackDelayInMins, TimeUnit.MINUTES);
        final Date maxAllowedTime = new Date(System.currentTimeMillis() - timelimitInMillis);

        final Map<User, FeedbackStorageObject> sessionFeedbacks = data.get(session);
        final List<User> affectedUsers = new ArrayList<User>();

        for (final Map.Entry<User, FeedbackStorageObject> entry : sessionFeedbacks.entrySet()) {
            final User user = entry.getKey();
            final FeedbackStorageObject feedback = entry.getValue();
            final boolean timeIsUp = feedback.getTimestamp().before(maxAllowedTime);
            if (timeIsUp) {
                sessionFeedbacks.remove(user);
                affectedUsers.add(user);
            }
        }
        return affectedUsers;
    }
}