retval[347] = new Countblank();

/* ====================================================================

   Licensed to the Apache Software Foundation (ASF) under one or more

   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

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package org.apache.poi.hssf.record.formula.functions;

import org.apache.poi.hssf.record.formula.eval.AreaEval;

import org.apache.poi.hssf.record.formula.eval.BlankEval;

import org.apache.poi.hssf.record.formula.eval.ErrorEval;

import org.apache.poi.hssf.record.formula.eval.NumberEval;

import org.apache.poi.hssf.record.formula.eval.RefEval;

import org.apache.poi.hssf.record.formula.eval.ValueEval;

import org.apache.poi.hssf.record.formula.functions.CountUtils.I_MatchPredicate;

/**

 * Implementation for the function COUNTBLANK

 * <p>

 *  Syntax: COUNTBLANK ( range )

 *    <table border="0" cellpadding="1" cellspacing="0" summary="Parameter descriptions">

 *      <tr><th>range&nbsp;&nbsp;&nbsp;</th><td>is the range of cells to count blanks</td></tr>

 *    </table>

 * </p>

 *

 * @author Mads Mohr Christensen

 */

public final class Countblank implements Function {

	public ValueEval evaluate(ValueEval[] args, int srcRowIndex, short srcColumnIndex) {

		switch(args.length) {

		case 1:

			// expected

			break;

		default:

			// TODO - it doesn't seem to be possible to enter COUNTBLANK() into Excel with the wrong arg count

			// perhaps this should be an exception

			return ErrorEval.VALUE_INVALID;

		}

		double result;

		if (args[0] instanceof RefEval) {

			result = CountUtils.countMatchingCell((RefEval) args[0], predicate);

		} else if (args[0] instanceof AreaEval) {

			result = CountUtils.countMatchingCellsInArea((AreaEval) args[0], predicate);

		} else {

			throw new IllegalArgumentException("Bad range arg type (" + args[0].getClass().getName() + ")");

		}

		return new NumberEval(result);

	}

	private static final I_MatchPredicate predicate = new I_MatchPredicate() {

		public boolean matches(ValueEval valueEval) {

			if(valueEval == BlankEval.INSTANCE) {

				return true;

			}

			// Note - only BlankEval counts

			return false;

		}

	};

}

	public void testCountBlank() {

		AreaEval range;

		ValueEval[] values;

		values = new ValueEval[] {

				new NumberEval(0),

				new StringEval(""),	// note - does not match blank

				BoolEval.TRUE,

				BoolEval.FALSE,

				ErrorEval.DIV_ZERO,

				BlankEval.INSTANCE,

		};

		range = EvalFactory.createAreaEval("A1:B3", values);

		confirmCountBlank(1, range);

		values = new ValueEval[] {

				new NumberEval(0),

				new StringEval(""),	// note - does not match blank

				BlankEval.INSTANCE,

				BoolEval.FALSE,

				BoolEval.TRUE,

				BlankEval.INSTANCE,

		};

		range = EvalFactory.createAreaEval("A1:B3", values);

		confirmCountBlank(2, range);

	}

	private static void confirmCountBlank(int expected, AreaEval range) {

		ValueEval[] args = { range };

		double result = NumericFunctionInvoker.invoke(new Countblank(), args);

		assertEquals(expected, result, 0);

	}

	public void testCounBlankFromSpreadsheet() {

		final String FILE_NAME = "countblankExamples.xls";

		final int START_ROW_IX = 1;

		final int COL_IX_ACTUAL = 3;

		final int COL_IX_EXPECTED = 4;

		int failureCount = 0;

		HSSFWorkbook wb = HSSFTestDataSamples.openSampleWorkbook(FILE_NAME);

		HSSFSheet sheet = wb.getSheetAt(0);

		HSSFFormulaEvaluator fe = new HSSFFormulaEvaluator(wb);

		int maxRow = sheet.getLastRowNum();

		for (int rowIx=START_ROW_IX; rowIx<maxRow; rowIx++) {

			HSSFRow row = sheet.getRow(rowIx);

			if(row == null) {

				continue;

			}

			HSSFCell cell = row.getCell(COL_IX_ACTUAL);

			CellValue cv = fe.evaluate(cell);

			double actualValue = cv.getNumberValue();

			double expectedValue = row.getCell(COL_IX_EXPECTED).getNumericCellValue();

			if (actualValue != expectedValue) {

				System.err.println("Problem with test case on row " + (rowIx+1) + " "

						+ "Expected = (" + expectedValue + ") Actual=(" + actualValue + ") ");

				failureCount++;

			}

		}

		if (failureCount > 0) {

			throw new AssertionFailedError(failureCount + " countblank evaluations failed. See stderr for more details");

		}

	}