/*
 * 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 - 2009 Pentaho Corporation and Contributors.  All rights reserved.
 */

package org.pentaho.reporting.libraries.formula.operators;

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.lvalues.TypeValuePair;

/**
 * This is a no-op-operator which is equal to "zero plus x".
 *
 * @author Thomas Morgner
 */
public class PlusSignOperator implements PrefixOperator
{
  private static final long serialVersionUID = 8127033177252320339L;

  public PlusSignOperator()
  {
  }

  public TypeValuePair evaluate(final FormulaContext context,
                                final TypeValuePair value1) throws EvaluationException
  {
    if (value1 == null)
    {
      // This is fatal, but should never happen.
      throw EvaluationException.getInstance(LibFormulaErrorValue.ERROR_UNEXPECTED_VALUE);
    }
    return value1;
  }

  public String toString()
  {
    return "+";
  }

}
