coordinator/src/main/java/org/apache/felix/coordination/impl/CoordinatorImpl.java

/*
 * 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.felix.coordination.impl;

import java.util.Collection;
import java.util.HashSet;
import java.util.TimerTask;

import org.apache.felix.service.coordination.Coordination;
import org.apache.felix.service.coordination.CoordinationException;
import org.apache.felix.service.coordination.Coordinator;
import org.apache.felix.service.coordination.Participant;
import org.osgi.framework.Bundle;

@SuppressWarnings("deprecation")
public class CoordinatorImpl implements Coordinator {

    private final Bundle owner;

    private final CoordinationMgr mgr;

    private final HashSet<Coordination> coordinations;

    CoordinatorImpl(final Bundle owner, final CoordinationMgr mgr) {
        this.owner = owner;
        this.mgr = mgr;
        this.coordinations = new HashSet<Coordination>();
    }

    /**
     * Ensure all active Coordinations started by this CoordinatorImpl instance
     * are terminated before the service is ungotten by the bundle.
     * <p>
     * Called by the Coordinator ServiceFactory when this CoordinatorImpl
     * instance is not used any longer by the owner bundle.
     *
     * @see FELIX-2671/OSGi Bug 104
     */
    void dispose() {
        final Coordination[] active;
        synchronized (coordinations) {
            if (coordinations.isEmpty()) {
                active = null;
            } else {
                active = coordinations.toArray(new CoordinationImpl[coordinations.size()]);
                coordinations.clear();
            }
        }

        if (active != null) {
            Throwable reason = new Exception("Coordinator service released");
            for (int i = 0; i < active.length; i++) {
                active[i].fail(reason);
            }
        }
    }

    public Coordination create(String name) {
        // TODO: check permission
        Coordination c = mgr.create(this, name);
        synchronized (coordinations) {
            coordinations.add(c);
        }
        return c;
    }

    public Coordination begin(String name) {
        // TODO: check permission
        return push(create(name));
    }

    public Coordination push(Coordination c) {
        // TODO: check permission
        return mgr.push(c);
    }

    public Coordination pop() {
        // TODO: check permission
        return mgr.pop();
    }

    public Coordination getCurrentCoordination() {
        // TODO: check permission
        return mgr.getCurrentCoordination();
    }

    public boolean alwaysFail(Throwable reason) {
        // TODO: check permission
        CoordinationImpl current = (CoordinationImpl) getCurrentCoordination();
        if (current != null) {
            current.mustFail(reason);
            return true;
        }
        return false;
    }

    public Collection<Coordination> getCoordinations() {
        // TODO: check permission
        return mgr.getCoordinations();
    }

    public boolean participate(Participant participant)
            throws CoordinationException {
        // TODO: check permission
        Coordination current = getCurrentCoordination();
        if (current != null) {
            current.participate(participant);
            return true;
        }
        return false;
    }

    void unregister(final CoordinationImpl c) {
        mgr.unregister(c);
        synchronized (coordinations) {
            coordinations.remove(c);
        }
    }

    void schedule(final TimerTask task, final long delay) {
        mgr.schedule(task, delay);
    }

    void lockParticipant(final Participant p, final CoordinationImpl c) {
        mgr.lockParticipant(p, c);
    }

    void releaseParticipant(final Participant p) {
        mgr.releaseParticipant(p);
    }
}