//$Id: CastFunction.java 7368 2005-07-04 02:54:27Z oneovthafew $
package org.hibernate.dialect.function;
import java.util.List;
import org.hibernate.QueryException;
import org.hibernate.engine.Mapping;
import org.hibernate.engine.SessionFactoryImplementor;
import org.hibernate.type.Type;
import org.hibernate.type.TypeFactory;
/**
* ANSI-SQL style <tt>cast(foo as type)</tt> where the type is
* a Hibernate type
* @author Gavin King
*/
public class CastFunction implements SQLFunction {
public Type getReturnType(Type columnType, Mapping mapping) throws QueryException {
return columnType; //note there is a wierd implementation in the client side
}
public boolean hasArguments() {
return true;
}
public boolean hasParenthesesIfNoArguments() {
return true;
}
public String render(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 = TypeFactory.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 getTypeName() 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 + ')';
}
}
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