/*******************************************************************************
* Copyright (c) 1998, 2010 Oracle. All rights reserved.
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v1.0 and Eclipse Distribution License v. 1.0
* which accompanies this distribution.
* The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v10.html
* and the Eclipse Distribution License is available at
* http://www.eclipse.org/org/documents/edl-v10.php.
*
* Contributors:
* Oracle - initial API and implementation from Oracle TopLink
******************************************************************************/
package org.eclipse.persistence.internal.jpa.parsing;
import org.eclipse.persistence.expressions.*;
import org.eclipse.persistence.exceptions.JPQLException;
import org.eclipse.persistence.queries.ObjectLevelReadQuery;
import org.eclipse.persistence.queries.ReportQuery;
/**
* INTERNAL
* <p><b>Purpose</b>: Represent a SIZE function
* <p><b>Responsibilities</b>:<ul>
* <li> Generate the correct expression for SIZE
* </ul>
*/
public class SizeNode extends ArithmeticFunctionNode {
/**
* Return a new SizeNode.
*/
public SizeNode() {
super();
}
/**
* INTERNAL
* Apply this node to the passed query
*/
public void applyToQuery(ObjectLevelReadQuery theQuery, GenerationContext context) {
if (theQuery.isReportQuery()) {
ReportQuery reportQuery = (ReportQuery)theQuery;
reportQuery.addAttribute("size", getLeft().generateExpression(context).count(), (Class)getType());
reportQuery.addGrouping(getLeft().getLeft().generateExpression(context));
}
}
/**
* INTERNAL
* Validate node and calculate its type.
*/
public void validate(ParseTreeContext context) {
if (left != null) {
left.validate(context);
}
TypeHelper typeHelper = context.getTypeHelper();
setType(typeHelper.getIntType());
}
/**
* INTERNAL
* Generate the EclipseLink expression for this node
*/
public Expression generateExpression(GenerationContext context) {
DotNode dotNode = (DotNode)getLeft();
Node prefix = dotNode.getLeft();
String variableName = ((AttributeNode)dotNode.getRight()).getAttributeName();
// check whether variable denotes a collection valued field
if (!dotNode.endsWithCollectionField(context)) {
throw JPQLException.invalidSizeArgument(
context.getParseTreeContext().getQueryInfo(),
getLine(), getColumn(), variableName);
}
Expression whereClause = prefix.generateExpression(context);
whereClause = whereClause.size(variableName);
return whereClause;
}
}