/*
* 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) 2001 - 2009 Object Refinery Ltd, Pentaho Corporation and Contributors.. All rights reserved.
*/
package org.pentaho.reporting.engine.classic.core.function.formula;
import org.pentaho.reporting.engine.classic.core.function.ReportFormulaContext;
import org.pentaho.reporting.engine.classic.core.wizard.DataAttributes;
import org.pentaho.reporting.engine.classic.core.wizard.DefaultDataAttributeContext;
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.coretypes.AnyType;
import org.pentaho.reporting.libraries.base.util.ObjectUtilities;
/**
* Todo: Document Me
*
* @author Thomas Morgner
*/
public class MetaDataFunction implements Function
{
public MetaDataFunction()
{
}
public String getCanonicalName()
{
return "METADATA";
}
public TypeValuePair evaluate(final FormulaContext context,
final ParameterCallback parameters) throws EvaluationException
{
final int parameterCount = parameters.getParameterCount();
if (parameterCount != 3 && parameterCount != 4)
{
throw EvaluationException.getInstance(LibFormulaErrorValue.ERROR_ARGUMENTS_VALUE);
}
final String fieldName = context.getTypeRegistry().convertToText(parameters.getType(0), parameters.getValue(0));
final String metaNamespace = context.getTypeRegistry().convertToText(parameters.getType(1), parameters.getValue(1));
final String metaName = context.getTypeRegistry().convertToText(parameters.getType(2), parameters.getValue(2));
final Class type;
if (parameterCount == 4)
{
final String typeStr = context.getTypeRegistry().convertToText(parameters.getType(3), parameters.getValue(3));
final ClassLoader loader = ObjectUtilities.getClassLoader(MetaDataFunction.class);
try
{
type = Class.forName(typeStr, false, loader);
}
catch (ClassNotFoundException e)
{
throw EvaluationException.getInstance(LibFormulaErrorValue.ERROR_UNEXPECTED_VALUE);
}
}
else
{
type = String.class;
}
final ReportFormulaContext rfc = (ReportFormulaContext) context;
final DataAttributes data = rfc.getDataSchema().getAttributes(fieldName);
if (data == null)
{
throw EvaluationException.getInstance(LibFormulaErrorValue.ERROR_INVALID_ARGUMENT_VALUE);
}
final DefaultDataAttributeContext attributeContext =
new DefaultDataAttributeContext(rfc.getProcessingContext().getOutputProcessorMetaData(),
rfc.getLocalizationContext().getLocale());
final Object o = data.getMetaAttribute(metaNamespace, metaName, type, attributeContext);
return new TypeValuePair(AnyType.TYPE, o);
}
}