//$Id: GroupByParser.java 4907 2004-12-08 00:24:14Z oneovthafew $
package org.hibernate.hql.classic;
import org.hibernate.QueryException;
import org.hibernate.util.StringHelper;
/**
* Parses the GROUP BY clause of an aggregate query
*/
public class GroupByParser implements Parser {
//this is basically a copy/paste of OrderByParser ... might be worth refactoring
// This uses a PathExpressionParser but notice that compound paths are not valid,
// only bare names and simple paths:
// SELECT p FROM p IN CLASS eg.Person GROUP BY p.Name, p.Address, p
// The reason for this is SQL doesn't let you sort by an expression you are
// not returning in the result set.
private final PathExpressionParser pathExpressionParser;
{
pathExpressionParser = new PathExpressionParser();
pathExpressionParser.setUseThetaStyleJoin( true ); //TODO: would be nice to use false, but issues with MS SQL
}
public void token(String token, QueryTranslatorImpl q) throws QueryException {
if ( q.isName( StringHelper.root( token ) ) ) {
ParserHelper.parse( pathExpressionParser, q.unalias( token ), ParserHelper.PATH_SEPARATORS, q );
q.appendGroupByToken( pathExpressionParser.getWhereColumn() );
pathExpressionParser.addAssociation( q );
}
else {
q.appendGroupByToken( token );
}
}
public void start(QueryTranslatorImpl q) throws QueryException {
}
public void end(QueryTranslatorImpl q) throws QueryException {
}
}
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