/*
* 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 - 2013 Object Refinery Ltd, Pentaho Corporation and Contributors.. All rights reserved.
*/
package org.pentaho.reporting.engine.classic.core.function.bool;
import org.pentaho.reporting.engine.classic.core.function.AbstractExpression;
import org.pentaho.reporting.engine.classic.core.function.ExpressionRuntime;
import javax.swing.table.TableModel;
/**
* An expression that checks, whether the current report has a non-empty datasource.
*
* @author Thomas Morgner
* @deprecated Use a formula instead or make proper use of the No-Data band.
*/
public class IsEmptyDataExpression extends AbstractExpression {
/**
* Default Constructor.
*/
public IsEmptyDataExpression() {
}
/**
* Checks whether the report has a data-source and wether the datasource is empty. A datasource is considered empty,
* if it contains no rows. The number of columns is not evaluated.
*
* @return the value of the function.
*/
public Object getValue() {
final ExpressionRuntime runtime = getRuntime();
if ( runtime == null ) {
return null;
}
final TableModel data = runtime.getData();
if ( data == null ) {
return null;
}
if ( data.getRowCount() == 0 ) {
return Boolean.TRUE;
}
return Boolean.FALSE;
}
}