Ptidej-v5.2-master/Ptidej Reporting Tests/src/net/sf/jasperreports/engine/fill/JRParameterDefaultValuesEvaluator.java
/*
 * ============================================================================
 * GNU Lesser General Public License
 * ============================================================================
 *
 * JasperReports - Free Java report-generating library.
 * Copyright (C) 2001-2006 JasperSoft Corporation http://www.jaspersoft.com
 * 
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 * 
 * This library 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 library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307, USA.
 * 
 * JasperSoft Corporation
 * 303 Second Street, Suite 450 North
 * San Francisco, CA 94107
 * http://www.jaspersoft.com
 */
package net.sf.jasperreports.engine.fill;

import java.util.HashMap;
import java.util.Map;

import net.sf.jasperreports.engine.JRDataset;
import net.sf.jasperreports.engine.JRException;
import net.sf.jasperreports.engine.JRGroup;
import net.sf.jasperreports.engine.JRParameter;
import net.sf.jasperreports.engine.JasperReport;


/**
 * Utility class to be used to evaluate parameter default value expressions for a report
 * without actually filling it.
 * 
 * @author Lucian Chirita (lucianc@users.sourceforge.net)
 * @version $Id: JRParameterDefaultValuesEvaluator.java,v 1.1 2008/09/29 16:20:01 guehene Exp $
 */
public class JRParameterDefaultValuesEvaluator
{

	/**
	 * Evaluates the default values for the parameters of a report.
	 * 
	 * @param report the report
	 * @param initialParameters initial parameter value map
	 * @return a map containing parameter values indexed by parameter names
	 * @throws JRException
	 */
	public static Map evaluateParameterDefaultValues(JasperReport report, Map initialParameters) throws JRException
	{
		Map valuesMap = initialParameters == null ? new HashMap() : new HashMap(initialParameters);
		
		ObjectFactory factory = new ObjectFactory();
		JRDataset reportDataset = report.getMainDataset();
		JRFillDataset fillDataset = factory.getDataset(reportDataset);
		fillDataset.createCalculator(report);
		fillDataset.initCalculator();

		JRResourcesFillUtil.ResourcesFillContext resourcesContext = 
			JRResourcesFillUtil.setResourcesFillContext(valuesMap);
		try
		{
			fillDataset.setParameterValues(valuesMap);
			
			Map parameterValues = new HashMap();
			JRParameter[] parameters = reportDataset.getParameters();
			for (int i = 0; i < parameters.length; i++)
			{
				JRParameter param = parameters[i];
				if (!param.isSystemDefined())
				{
					String name = param.getName();
					Object value = fillDataset.getParameterValue(name);
					parameterValues.put(name, value);
				}
			}
			
			return parameterValues;
		}
		finally
		{
			JRResourcesFillUtil.revertResourcesFillContext(resourcesContext);
		}
	}
	
	protected static class ObjectFactory extends JRFillObjectFactory
	{
		protected ObjectFactory()
		{
			super((JRBaseFiller) null, null);
		}

		protected JRFillGroup getGroup(JRGroup group)
		{
			return super.getGroup(null);
		}
	}
	
}
