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* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
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*
* http://www.apache.org/licenses/LICENSE-2.0
*
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package org.apache.cayenne;
import org.apache.cayenne.graph.GraphEvent;
/**
* A listener of {@link org.apache.cayenne.DataChannel} lifecycle events. Changes
* related to an event are attached as a GraphDiff. If a listener needs to process these
* changes, the easiest way to do that is via GraphChangeHandler "visitor":
*
* <pre>
* public void graphChanged(GraphEvent event) {
* GraphChangeHandler handler = ..;
* event.getDiff().apply(handler);
* }
* </pre>
*
* @since 1.2
*/
public interface DataChannelListener {
/**
* Notifies implementing object of the changes that were performed to the object graph
* externally, not by one of the channel ObjectContexts.
*/
void graphChanged(GraphEvent event);
/**
* Notifies implementing object that one of the channel ObjectContexts flushed its
* changes to the channel.
*/
void graphFlushed(GraphEvent event);
/**
* Notifies implementing object that one of the channel ObjectContexts initiated a
* rollback.
*/
void graphRolledback(GraphEvent event);
}