/*
* Hibernate, Relational Persistence for Idiomatic Java
*
* Copyright (c) 2008, Red Hat Middleware LLC or third-party contributors as
* indicated by the @author tags or express copyright attribution
* statements applied by the authors. All third-party contributions are
* distributed under license by Red Hat Middleware LLC.
*
* This copyrighted material is made available to anyone wishing to use, modify,
* copy, or redistribute it subject to the terms and conditions of the GNU
* Lesser General Public License, as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
* for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this distribution; if not, write to:
* Free Software Foundation, Inc.
* 51 Franklin Street, Fifth Floor
* Boston, MA 02110-1301 USA
*
*/
package org.hibernate.sql.ordering.antlr;
import java.io.StringReader;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.hibernate.HibernateException;
import org.hibernate.hql.ast.util.ASTPrinter;
/**
* A translator which coordinates translation of an <tt>order-by</tt> mapping.
*
* @author Steve Ebersole
*/
public class OrderByFragmentTranslator {
private static final Logger log = LoggerFactory.getLogger( OrderByFragmentTranslator.class );
public final TranslationContext context;
public OrderByFragmentTranslator(TranslationContext context) {
this.context = context;
}
/**
* The main contract, performing the transaction.
*
* @param fragment The <tt>order-by</tt> mapping fragment to be translated.
*
* @return The translated fragment.
*/
public String render(String fragment) {
GeneratedOrderByLexer lexer = new GeneratedOrderByLexer( new StringReader( fragment ) );
OrderByFragmentParser parser = new OrderByFragmentParser( lexer, context );
try {
parser.orderByFragment();
}
catch ( HibernateException e ) {
throw e;
}
catch ( Throwable t ) {
throw new HibernateException( "Unable to parse order-by fragment", t );
}
if ( log.isTraceEnabled() ) {
ASTPrinter printer = new ASTPrinter( OrderByTemplateTokenTypes.class );
log.trace( printer.showAsString( parser.getAST(), "--- {order-by fragment} ---" ) );
}
OrderByFragmentRenderer renderer = new OrderByFragmentRenderer();
try {
renderer.orderByFragment( parser.getAST() );
}
catch ( HibernateException e ) {
throw e;
}
catch ( Throwable t ) {
throw new HibernateException( "Unable to render parsed order-by fragment", t );
}
return renderer.getRenderedFragment();
}
}