org.eclipse.persistence.internal.sequencing.SequencingFactory Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of eclipselink Show documentation
EclipseLink build based upon Git transaction 346465e
There is a newer version: 5.0.0-B03
/*******************************************************************************
 * Copyright (c) 1998, 2013 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 v1.0 and Eclipse Distribution License v. 1.0 
 * which accompanies this distribution. 
 * The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v10.html
 * and the Eclipse Distribution License is available at 
 * http://www.eclipse.org/org/documents/edl-v10.php.
 *
 * Contributors:
 *     Oracle - initial API and implementation from Oracle TopLink
 ******************************************************************************/  
package org.eclipse.persistence.internal.sequencing;

import org.eclipse.persistence.sessions.server.ClientSession;
import org.eclipse.persistence.sessions.remote.DistributedSession;
import org.eclipse.persistence.internal.sessions.remote.RemoteConnection;
import org.eclipse.persistence.internal.sessions.AbstractSession;
import org.eclipse.persistence.internal.sessions.DatabaseSessionImpl;
import org.eclipse.persistence.sessions.broker.SessionBroker;

/**
 * SequencingFactory is private to EclipseLink.
 * It instantiates sequencing classes for sessions.
 * It allows sequencing classes to be encapsulated in
 * this package.
 *
 * @see ClientSessionSequencing
 * @see RemoteConnectionSequencing
 * @see SessionBrokerSequencing
 * @see SequencingManager
 *
 */
public class SequencingFactory {

    /**
    * INTERNAL:
    * Takes a potential owner - a Session, returns Sequencing object.
    * Note that before creating a Sequencing object there is a check performed
    * to determine whether the object could be created.
    */
    public static Sequencing createSequencing(AbstractSession session) {
        Sequencing sequencing = null;
        if (session.isClientSession()) {
            ClientSession cs = (ClientSession)session;
            if (ClientSessionSequencing.sequencingServerExists(cs)) {
                sequencing = new ClientSessionSequencing(cs);
            }
        } else if (session.isRemoteSession()) {
            RemoteConnection con = ((DistributedSession)session).getRemoteConnection();
            if (RemoteConnectionSequencing.masterSequencingExists(con)) {
                sequencing = new RemoteConnectionSequencing(con);
            }
        } else if (session.isBroker()) {
            SessionBroker br = (SessionBroker)session;
            if (SessionBrokerSequencing.atLeastOneSessionHasSequencing(br)) {
                sequencing = new SessionBrokerSequencing(br);
            }
        }
        return sequencing;
    }

    /**
    * INTERNAL:
    * Takes a potential owner - a DatabaseSession, returns SequencingHome object.
    * Only DatabaseSession and ServerSession should be passed (not SessionBroker).
    */
    public static SequencingHome createSequencingHome(DatabaseSessionImpl ownerSession) {
        SequencingHome home = null;
        if (!ownerSession.isBroker()) {
            home = new SequencingManager(ownerSession);
        }
        return home;
    }
}