/* ====================================================================
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contributor license agreements. See the NOTICE file distributed with
this work for additional information regarding copyright ownership.
The ASF licenses this file to You under the Apache License, Version 2.0
(the "License"); you may not use this file except in compliance with
the License. You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
==================================================================== */
package org.apache.poi.ss.formula.functions;
import org.apache.poi.ss.formula.eval.AreaEval;
import org.apache.poi.ss.formula.eval.ErrorEval;
import org.apache.poi.ss.formula.eval.RefEval;
import org.apache.poi.ss.formula.eval.StringEval;
import org.apache.poi.ss.formula.eval.ValueEval;
/**
* Implementation of Excel T() function
* <p/>
* If the argument is a text or error value it is returned unmodified. All other argument types
* cause an empty string result. If the argument is an area, the first (top-left) cell is used
* (regardless of the coordinates of the evaluating formula cell).
*/
public final class T extends Fixed1ArgFunction {
public ValueEval evaluate(int srcRowIndex, int srcColumnIndex, ValueEval arg0) {
ValueEval arg = arg0;
if (arg instanceof RefEval) {
// always use the first sheet
RefEval re = (RefEval)arg;
arg = re.getInnerValueEval(re.getFirstSheetIndex());
} else if (arg instanceof AreaEval) {
// when the arg is an area, choose the top left cell
arg = ((AreaEval) arg).getRelativeValue(0, 0);
}
if (arg instanceof StringEval) {
// Text values are returned unmodified
return arg;
}
if (arg instanceof ErrorEval) {
// Error values also returned unmodified
return arg;
}
// for all other argument types the result is empty string
return StringEval.EMPTY_INSTANCE;
}
}