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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.exp;
/**
* Expression visitor interface. Defines callback methods invoked when
* walking the expression using {@link Expression#traverse(TraversalHandler)}.
*
*/
public interface TraversalHandler {
/**
* Called during traversal after a child of expression
* has been visited.
*/
public void finishedChild(
Expression node,
int childIndex,
boolean hasMoreChildren);
/**
* Called during the traversal before an expression node children
* processing is started.
*
* @since 1.1
*/
public void startNode(Expression node, Expression parentNode);
/**
* Called during the traversal after an expression node children
* processing is finished.
*
* @since 1.1
*/
public void endNode(Expression node, Expression parentNode);
/**
* Called during the traversal when a leaf non-expression node
* is encountered.
*/
public void objectNode(Object leaf, Expression parentNode);
}