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* http://www.apache.org/licenses/LICENSE-2.0
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package org.apache.cayenne.ejbql;
/**
* An abstract EJBQL expression interface.
*
* @since 3.0
*/
public interface EJBQLExpression {
/**
* Accepts a visitor, calling appropriate visitor method. If the visitor method
* returns true, visits all children, otherwise stops.
*/
void visit(EJBQLExpressionVisitor visitor);
/**
* Returns a number of child operands of this expression node.
*/
int getChildrenCount();
/**
* Returns a child expression node at the specified index.
*/
EJBQLExpression getChild(int index);
/**
* Returns a text property of the node.
*/
String getText();
/**
* Returns an optional boolean flag that negates the value of the expression.
*/
boolean isNegated();
}