org.hibernate.dialect.function.CastFunction Maven / Gradle / Ivy
/*
* Hibernate, Relational Persistence for Idiomatic Java
*
* Copyright (c) 2010, Red Hat Inc. 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 Inc.
*
* 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.dialect.function;
import java.util.List;
import org.hibernate.QueryException;
import org.hibernate.engine.spi.Mapping;
import org.hibernate.engine.spi.SessionFactoryImplementor;
import org.hibernate.type.Type;
/**
* ANSI-SQL style cast(foo as type) where the type is
* a Hibernate type
* @author Gavin King
*/
public class CastFunction implements SQLFunction {
public boolean hasArguments() {
return true;
}
public boolean hasParenthesesIfNoArguments() {
return true;
}
public Type getReturnType(Type columnType, Mapping mapping) throws QueryException {
return columnType; // this is really just a guess, unless the caller properly identifies the 'type' argument here
}
public String render(Type columnType, List args, SessionFactoryImplementor factory) throws QueryException {
if ( args.size()!=2 ) {
throw new QueryException("cast() requires two arguments");
}
String type = (String) args.get(1);
int[] sqlTypeCodes = factory.getTypeResolver().heuristicType(type).sqlTypes(factory);
if ( sqlTypeCodes.length!=1 ) {
throw new QueryException("invalid Hibernate type for cast()");
}
String sqlType = factory.getDialect().getCastTypeName( sqlTypeCodes[0] );
if (sqlType==null) {
//TODO: never reached, since getExplicitHibernateTypeName() actually throws an exception!
sqlType = type;
}
/*else {
//trim off the length/precision/scale
int loc = sqlType.indexOf('(');
if (loc>-1) {
sqlType = sqlType.substring(0, loc);
}
}*/
return "cast(" + args.get(0) + " as " + sqlType + ')';
}
}