foundation/org.eclipse.persistence.core/src/main/java/org/eclipse/persistence/sessions/coordination/broadcast/BroadcastTransportManager.java

/*
 * Copyright (c) 1998, 2021 Oracle and/or its affiliates. All rights reserved.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v. 2.0 which is available at
 * http://www.eclipse.org/legal/epl-2.0,
 * or the Eclipse Distribution License v. 1.0 which is available at
 * http://www.eclipse.org/org/documents/edl-v10.php.
 *
 * SPDX-License-Identifier: EPL-2.0 OR BSD-3-Clause
 */

// Contributors:
//     Oracle - initial API and implementation from Oracle TopLink
package org.eclipse.persistence.sessions.coordination.broadcast;

import org.eclipse.persistence.internal.sessions.coordination.RemoteConnection;

import org.eclipse.persistence.sessions.coordination.DiscoveryManager;
import org.eclipse.persistence.sessions.coordination.RemoteCommandManager;
import org.eclipse.persistence.sessions.coordination.ServiceId;
import org.eclipse.persistence.sessions.coordination.TransportManager;

/**
 * <p>
 * <b>Purpose</b>: Base class transport manager for broadcasting RCM protocols: JMS and Oc4jJGroups.
 * </p><p>
 * <b>Description</b>: The class doesn't use DiscoveryManager - instead
 * the class (and it's ancestors) implement createConnections method
 * that creates all the necessary connections. This method is called
 * by RemoteCommendManager during initialization.
 * </p>
 * @author Andrei Ilitchev
 * @since OracleAS TopLink 11<i>g</i> (11.1.1)
 */
public abstract class BroadcastTransportManager extends TransportManager {

    // JNDI topic name
    protected String topicName;

    protected BroadcastTransportManager() {
        initialize();
    }

    protected BroadcastTransportManager(RemoteCommandManager rcm) {
        this.rcm = rcm;
        rcm.setTransportManager(this);
        initialize();
    }

    /**
     * ADVANCED:
     * BroadcastTransportManager doesn't use DiscoveryManager - instead RemoteCommandManager
     * calls createConnections method during initialization.
     */
    @Override
    public DiscoveryManager createDiscoveryManager() {
        return null;
    }

    /**
     * INTERNAL:
     * BroadcastTransportManager doesn't use DiscoveryManager
     * (createDiscoveryManager method returns null) therefore
     * this method called during RCM initialization to create all the necessary connections.
     * BroadcastTransportManager ancestors may need to override this method.
     */
    @Override
    public void createConnections() {
        createLocalConnection();
    }

    /**
     * INTERNAL:
     * No-op implementation of super abstract method since there is only one connection to a known topic.
     */
    @Override
    public RemoteConnection createConnection(ServiceId serviceId) {
        return null;
    }

    /**
     * INTERNAL:
     * Add a remote Connection to a remote service.
     */
    @Override
    public void addConnectionToExternalService(RemoteConnection connection) {
        // nothing to do
    }

    /**
     * INTERNAL:
     * Prepare receiving messages by registering this connection as a listener to the Subscriber.
     * This method is called by the remote command manager when this service should connect back
     * ('handshake') to the service from which this remote connection came.
     */
    @Override
    public void connectBackToRemote(RemoteConnection connection) throws Exception {
        // nothing to do
    }

    /**
     * PUBLIC:
     * Return the topic name that this TransportManager will be connecting to.
     */
    public String getTopicName() {
        return topicName;
    }

    /**
     * PUBLIC:
     * Configure the Topic name for the Topic that this TransportManager will be connecting to.
     * For some subclasses (JMS) this is a required setting and must be set;
     * for other (Oc4jJGroups) it's typically not set.
     */
    public void setTopicName(String newTopicName) {
        topicName = newTopicName;
    }
}