Check and fix issue when sheets are added while an existing workbook-evaluator is used.

git-svn-id: https://svn.apache.org/repos/asf/poi/trunk@1894680 13f79535-47bb-0310-9956-ffa450edef68

poi-ooxml/src/main/java/org/apache/poi/xssf/usermodel/XSSFEvaluationWorkbook.java

@@ -17,6 +17,9 @@
 
 package org.apache.poi.xssf.usermodel;
 
+import java.util.HashMap;
+import java.util.Map;
+
 import org.apache.poi.ss.formula.EvaluationCell;
 import org.apache.poi.ss.formula.EvaluationSheet;
 import org.apache.poi.ss.formula.FormulaParser;
@@ -29,8 +32,8 @@ import org.apache.poi.util.Internal;
  */
 @Internal
 public final class XSSFEvaluationWorkbook extends BaseXSSFEvaluationWorkbook {
-    private XSSFEvaluationSheet[] _sheetCache;
-    
+    private final Map<XSSFSheet, XSSFEvaluationSheet> _sheetCache = new HashMap<>();
+
     public static XSSFEvaluationWorkbook create(XSSFWorkbook book) {
         if (book == null) {
             return null;
@@ -48,9 +51,9 @@ public final class XSSFEvaluationWorkbook extends BaseXSSFEvaluationWorkbook {
     @Override
     public void clearAllCachedResultValues() {
         super.clearAllCachedResultValues();
-        _sheetCache = null;
+        _sheetCache.clear();
     }
-    
+
     @Override
     public int getSheetIndex(EvaluationSheet evalSheet) {
         XSSFSheet sheet = ((XSSFEvaluationSheet)evalSheet).getXSSFSheet();
@@ -59,25 +62,22 @@ public final class XSSFEvaluationWorkbook extends BaseXSSFEvaluationWorkbook {
 
     @Override
     public EvaluationSheet getSheet(int sheetIndex) {
-        // Performance optimization: build sheet cache the first time this is called
-        // to avoid re-creating the XSSFEvaluationSheet each time a new cell is evaluated
+		// verify index and let the method in _uBook throw the exception so we report
+		// it the same way as in other places
+		if (sheetIndex < 0 || sheetIndex >= _uBook.getNumberOfSheets()) {
+			// this will throw an exception now as the index is out of bounds
+			_uBook.getSheetAt(sheetIndex);
+		}
+
+        // Performance optimization: build sheet cache for each sheet to avoid re-creating
+		// the XSSFEvaluationSheet each time a new cell is evaluated
         // EvaluationWorkbooks make not guarantee to synchronize changes made to
         // the underlying workbook after the EvaluationWorkbook is created.
-        if (_sheetCache == null) {
-            final int numberOfSheets = _uBook.getNumberOfSheets();
-            _sheetCache = new XSSFEvaluationSheet[numberOfSheets];
-            for (int i=0; i < numberOfSheets; i++) {
-                _sheetCache[i] = new XSSFEvaluationSheet(_uBook.getSheetAt(i));
-            }
-        }
-        if (sheetIndex < 0 || sheetIndex >= _sheetCache.length) {
-            // do this to reuse the out-of-bounds logic and message from XSSFWorkbook
-            _uBook.getSheetAt(sheetIndex);
-        }
-        return _sheetCache[sheetIndex];
+		final XSSFSheet sheet = _uBook.getSheetAt(sheetIndex);
+        return _sheetCache.computeIfAbsent(sheet, rows -> new XSSFEvaluationSheet(sheet));
     }
 
-    @Override    
+    @Override
     public Ptg[] getFormulaTokens(EvaluationCell evalCell) {
         final XSSFCell cell = ((XSSFEvaluationCell)evalCell).getXSSFCell();
         final int sheetIndex = _uBook.getSheetIndex(cell.getSheet());

poi-ooxml/src/test/java/org/apache/poi/xssf/usermodel/TestXSSFEvaluationWorkbook.java

@@ -0,0 +1,80 @@
+/* ====================================================================
+   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
+   limitations under the License.
+==================================================================== */
+
+package org.apache.poi.xssf.usermodel;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import org.apache.poi.ss.usermodel.Cell;
+import org.apache.poi.ss.usermodel.FormulaEvaluator;
+import org.apache.poi.ss.usermodel.Row;
+import org.apache.poi.ss.usermodel.Sheet;
+import org.apache.poi.ss.usermodel.Workbook;
+import org.apache.poi.ss.util.CellRangeAddress;
+import org.junit.jupiter.api.Test;
+
+class TestXSSFEvaluationWorkbook {
+
+	@Test
+	void testRefToBlankCellInArrayFormula() {
+		Workbook wb = new XSSFWorkbook();
+
+		FormulaEvaluator formulaEvaluator = wb.getCreationHelper().createFormulaEvaluator();
+		verifySheet(wb, formulaEvaluator);
+
+		verifySheet(wb, formulaEvaluator);
+
+		wb.getCreationHelper().createFormulaEvaluator().evaluateAll();
+	}
+
+	private void verifySheet(Workbook wb, FormulaEvaluator formulaEvaluator) {
+		Sheet sheet = wb.createSheet();
+		Row row = sheet.createRow(0);
+		Cell cellA1 = row.createCell(0);
+		Cell cellB1 = row.createCell(1);
+		Cell cellC1 = row.createCell(2);
+		Row row2 = sheet.createRow(1);
+		Cell cellA2 = row2.createCell(0);
+		Cell cellB2 = row2.createCell(1);
+		Cell cellC2 = row2.createCell(2);
+		Row row3 = sheet.createRow(2);
+		Cell cellA3 = row3.createCell(0);
+		Cell cellB3 = row3.createCell(1);
+		Cell cellC3 = row3.createCell(2);
+
+		cellA1.setCellValue("1");
+		// cell B1 intentionally left blank
+		cellC1.setCellValue("3");
+
+		cellA2.setCellFormula("A1");
+		cellB2.setCellFormula("B1");
+		cellC2.setCellFormula("C1");
+
+		sheet.setArrayFormula("A1:C1", CellRangeAddress.valueOf("A3:C3"));
+
+		formulaEvaluator.evaluateAll();
+
+		assertEquals("1", cellA2.getStringCellValue());
+		assertEquals(0,cellB2.getNumericCellValue(), 0.00001);
+		assertEquals("3",cellC2.getStringCellValue());
+
+		assertEquals("1", cellA3.getStringCellValue());
+		assertEquals(0,cellB3.getNumericCellValue(), 0.00001);
+		assertEquals("3",cellC3.getStringCellValue());
+	}
+
+}