xpath_rwapi/src2/org/apache/xpath/expression/Visitor.java

/*
 * The Apache Software License, Version 1.1
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 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation and was
 * originally based on software copyright (c) 2002, International
 * Business Machines Corporation., http://www.ibm.com.  For more
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package org.apache.xpath.expression;

/**
 * Allows the traversal of XPath expression using the visitor pattern.  
 */
public interface Visitor {

	/**
	 * Visit path expression
     * @param path
     * @return true to continue visiting the container expression
	 */
	boolean visitPath(PathExpr path);

	/**
	 * Visit step expression
     * @param     
     * @return true to continue visiting the container expression
	 */
	boolean visitStep(StepExpr step);

	/**
	 * Visit literal expression
     * @param
     * * @return true to continue visiting the container expression
	 */
	boolean visitLiteral(Literal literal);
	
	/**
	 * Visit variable expression
	 * @param
	 * @return true to continue visiting the container expression
	 */
	boolean visitVariable(Variable var);

	/**
	 * Visit operator expression
     * @param
     * @return true to continue visiting the container expression
	 */
	boolean visitOperator(OperatorExpr operator);

	/**
	 * Visit conditional expression
	 * @return true to continue visiting the container expression
     * @param
	 */
	boolean visitConditional(ConditionalExpr condition);

	/**
	 * Visit for or quantified expression
     * @param
     * @return true to continue visiting the container expression
	 */
	boolean visitForOrQuantifiedExpr(ForAndQuantifiedExpr expr);
	
	/**
	 * Visit instance of expression
	 * @return true to continue visiting the container expression
	 */
	boolean visitInstanceOf(InstanceOfExpr expr);
	
	/**
	 * Visit 'castable as' expression
	 * @return true to continue visiting the container expression
	 */
	boolean visitCastableAs(CastableAsExpr expr);

}