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

import org.apache.cayenne.CayenneRuntimeException;
import org.apache.cayenne.event.EventBridge;

/**
 * A connection object used to interact with a remote Cayenne server. Connection supports
 * synchronous interaction via {@link #sendMessage(ClientMessage)} and asynchronous
 * listening for server events.
 * 
 * @since 1.2
 * @author Andrus Adamchik
 */
public interface ClientConnection {

    /**
     * Returns an EventBridge that receives remote server events. Caller would normally
     * register returned bridge with a local EventManager, thus allowing local listeners
     * to receive server events.
     * 
     * @return An EventBridge or null if server events are not supported.
     */
    EventBridge getServerEventBridge() throws CayenneRuntimeException;

    /**
     * Sends a synchronous ClientMessage to the server, returning a reply.
     */
    Object sendMessage(ClientMessage message) throws CayenneRuntimeException;
}
