/*
* This program is free software; you can redistribute it and/or modify it under the
* terms of the GNU Lesser General Public License, version 2.1 as published by the Free Software
* Foundation.
*
* You should have received a copy of the GNU Lesser General Public License along with this
* program; if not, you can obtain a copy at http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html
* or from the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
* 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.
*
* Copyright (c) 2006 - 2013 Pentaho Corporation and Contributors. All rights reserved.
*/
package org.pentaho.reporting.libraries.formula.function.text;
import org.pentaho.reporting.libraries.formula.EvaluationException;
import org.pentaho.reporting.libraries.formula.FormulaContext;
import org.pentaho.reporting.libraries.formula.LibFormulaErrorValue;
import org.pentaho.reporting.libraries.formula.function.Function;
import org.pentaho.reporting.libraries.formula.function.ParameterCallback;
import org.pentaho.reporting.libraries.formula.lvalues.TypeValuePair;
import org.pentaho.reporting.libraries.formula.typing.Type;
import org.pentaho.reporting.libraries.formula.typing.coretypes.TextType;
/**
* This function returns the given text value or a zero lenght string for non text type.
*
* @author Cedric Pronzato
*/
public class TFunction implements Function {
private static final TypeValuePair EMPTY_STRING = new TypeValuePair( TextType.TYPE, "" );
private static final long serialVersionUID = 5792821944649583654L;
public TFunction() {
}
public TypeValuePair evaluate( final FormulaContext context, final ParameterCallback parameters )
throws EvaluationException {
final int parameterCount = parameters.getParameterCount();
if ( parameterCount < 1 ) {
throw EvaluationException.getInstance( LibFormulaErrorValue.ERROR_ARGUMENTS_VALUE );
}
final Type type1 = parameters.getType( 0 );
final Object value1 = parameters.getValue( 0 );
if ( type1 instanceof TextType || value1 instanceof String ) {
return new TypeValuePair( TextType.TYPE, value1 );
} else {
return EMPTY_STRING;
}
}
public String getCanonicalName() {
return "T";
}
}