/*
***************************************************************************************
* Copyright (C) 2006 EsperTech, Inc. All rights reserved. *
* http://www.espertech.com/esper *
* http://www.espertech.com *
* ---------------------------------------------------------------------------------- *
* The software in this package is published under the terms of the GPL license *
* a copy of which has been included with this distribution in the license.txt file. *
***************************************************************************************
*/
package com.espertech.esper.epl.expression.visitor;
import com.espertech.esper.epl.declexpr.ExprDeclaredNode;
import com.espertech.esper.epl.expression.core.ExprNode;
import com.espertech.esper.epl.expression.subquery.ExprSubselectNode;
import java.util.ArrayList;
import java.util.List;
/**
* Visitor that collects {@link com.espertech.esper.epl.expression.subquery.ExprSubselectNode} instances only
* directly under alias expressions, and declared expressions, stopping at nested declared expressions.
*/
public class ExprNodeSubselectDeclaredNoTraverseVisitor implements ExprNodeVisitorWithParent {
private final ExprDeclaredNode declaration;
private final List<ExprSubselectNode> subselects;
/**
* Ctor.
*
* @param declaration declare node
*/
public ExprNodeSubselectDeclaredNoTraverseVisitor(ExprDeclaredNode declaration) {
this.declaration = declaration;
subselects = new ArrayList<ExprSubselectNode>(1);
}
public void reset() {
subselects.clear();
}
/**
* Returns a list of lookup expression nodes.
*
* @return lookup nodes
*/
public List<ExprSubselectNode> getSubselects() {
return subselects;
}
public boolean isVisit(ExprNode exprNode) {
return exprNode != declaration && !(exprNode instanceof ExprDeclaredNode);
}
public void visit(ExprNode exprNode, ExprNode parentExprNode) {
if (!(exprNode instanceof ExprSubselectNode)) {
return;
}
ExprSubselectNode subselectNode = (ExprSubselectNode) exprNode;
subselects.add(subselectNode);
}
}