/*
* 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.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;
import org.pentaho.reporting.libraries.formula.typing.TypeRegistry;
import org.pentaho.reporting.libraries.formula.typing.coretypes.TextType;
/**
* Concats two strings operator.
*
* @author Thomas Morgner
*/
public class ConcatOperator implements InfixOperator
{
private static final long serialVersionUID = 6579968694761281257L;
public ConcatOperator()
{
}
public TypeValuePair evaluate(final FormulaContext context,
final TypeValuePair value1,
final TypeValuePair value2)
throws EvaluationException
{
final TypeRegistry typeRegistry = context.getTypeRegistry();
// Error or empty string, that's the question ..
final Object raw1 = value1.getValue();
final Object raw2 = value2.getValue();
if (raw1 == null || raw2 == null)
{
throw EvaluationException.getInstance(LibFormulaErrorValue.ERROR_NA_VALUE);
}
final String text1 = typeRegistry.convertToText(value1.getType(), raw1);
final String text2 = typeRegistry.convertToText(value2.getType(), raw2);
if (text1 == null && text2 == null)
{
throw EvaluationException.getInstance
(LibFormulaErrorValue.ERROR_INVALID_ARGUMENT_VALUE);
}
if (text1 == null)
{
return new TypeValuePair(TextType.TYPE, text2);
}
if (text2 == null)
{
return new TypeValuePair(TextType.TYPE, text1);
}
return new TypeValuePair(TextType.TYPE, text1 + text2);
}
public int getLevel()
{
return 300;
}
public String toString()
{
return "&";
}
public boolean isLeftOperation()
{
return true;
}
/**
* Defines, whether the operation is associative. For associative operations,
* the evaluation order does not matter, if the operation appears more than
* once in an expression, and therefore we can optimize them a lot better than
* non-associative operations (ie. merge constant parts and precompute them
* once).
*
* @return true, if the operation is associative, false otherwise
*/
public boolean isAssociative()
{
return false;
}
}