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 *  to you under the Apache License, Version 2.0 (the
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package org.apache.cayenne.jpa;

import javax.persistence.EntityManager;

import org.apache.cayenne.DataChannel;

/**
 * An interface that allows to access Cayenne runtime hidden behind standard JPA classes.
 * To do that, simply cast an EntityManager returned by Cayenne provider to
 * "CayenneEntityManager". Note that a regular JPA application shouldn't normally attempt
 * to do that. Otherwise it will not be portable across JPA providers.
 * 
 * @author Andrus Adamchik
 */
public interface CayenneEntityManager extends EntityManager {

    /**
     * Returns a Cayenne {@link DataChannel} that is used to link EntityManager with
     * Cayenne runtime. DataChannel can be used for instance to obtain Cayenne metadata or
     * add listeners.
     */
    DataChannel getChannel();
}
