Optimizations and bugfixes of SXSSF logic

ooxml/XSSF/Streaming/SXSSFCell.cs

@@ -470,7 +470,8 @@ public void SetCellValue(DateTime? value)
                 return;
             }
 
-            SetCellValue(value.Value);
+            bool date1904 = ((SXSSFWorkbook)Sheet.Workbook).XssfWorkbook.IsDate1904();
+            SetCellValue(DateUtil.GetExcelDate(value.Value, date1904));
         }
 
         public void SetCellValue(double value)
@@ -821,8 +822,7 @@ private String ConvertCellValueToString(CellType cellType)
 
         public void SetCellValue(DateTime value)
         {
-            bool date1904 = Sheet.Workbook.IsDate1904();
-            SetCellValue(DateUtil.GetExcelDate(value, date1904));
+            SetCellValue((DateTime?)value);
         }
     }
 }

ooxml/XSSF/Streaming/SXSSFRow.cs

@@ -362,7 +362,7 @@ object IEnumerator.Current
             }
 
             public void Dispose()
-            {
+            { 
             }
 
             public IEnumerator<ICell> GetEnumerator()
@@ -411,9 +411,7 @@ object IEnumerator.Current
             }
 
             public void Dispose()
-            {
-                throw new NotImplementedException();
-            }
+            { }
 
             public IEnumerator<ICell> GetEnumerator()
             {

ooxml/XSSF/Streaming/SXSSFSheet.cs

@@ -678,7 +678,7 @@ public IRow CreateRow(int rownum)
             {
                 try
                 {
-                    FlushRows(_randomAccessWindowSize);
+                    flushRows(_randomAccessWindowSize, false);
                 }
                 catch (IOException ioe)
                 {
@@ -1243,6 +1243,25 @@ public bool Dispose()
             return _writer.Dispose();
         }
         /**
+ * Specifies how many rows can be accessed at most via getRow().
+ * The exeeding rows (if any) are flushed to the disk while rows
+ * with lower index values are flushed first.
+ */
+        private void FlushRows(int remaining, bool flushOnDisk)
+        {
+            KeyValuePair<int, SXSSFRow>? lastRow = null;
+            var flushedRowsCount = 0;
+            while (_rows.Count > remaining)
+            {
+                flushedRowsCount++;
+                lastRow = flushOneRow();
+            }
+            if (remaining == 0) 
+                allFlushed = true;
+
+            if (lastRow != null && flushOnDisk)
+                _writer.FlushRows(flushedRowsCount, lastRow.Value.Key, lastRow.Value.Value.LastCellNum);
+       }
          * Are all rows flushed to disk?
          */
         public bool AllRowsFlushed
@@ -1262,20 +1281,24 @@ public int LastFlushedRowNumber
                 return lastFlushedRowNumber;
             }
         }
-        /**
-         * Specifies how many rows can be accessed at most via getRow().
-         * The exeeding rows (if any) are flushed to the disk while rows
-         * with lower index values are flushed first.
-         */
-        private void FlushRows(int remaining)
+
+        public void FlushRows()
         {
-            while (_rows.Count > remaining) FlushOneRow();
-            if (remaining == 0) allFlushed = true;
+            FlushRows(0, true);
         }
 
-        public void FlushRows()
+        private KeyValuePair<int, SXSSFRow>? flushOneRow()
         {
-            FlushRows(0);
+            if (_rows.Count == 0)
+                return null;
+
+            var firstRow = _rows.FirstOrDefault();
+            // Update the best fit column widths for auto-sizing just before the rows are flushed
+            // _autoSizeColumnTracker.UpdateColumnWidths(row);
+            _writer.WriteRow(firstRow.Key, firstRow.Value);
+            _rows.Remove(firstRow.Key);
+            lastFlushedRowNumber = firstRow.Key;
+            return firstRow;
         }
 
         private void FlushOneRow()
@@ -1299,7 +1322,8 @@ private void FlushOneRow()
         public Stream GetWorksheetXMLInputStream()
         {
             // flush all remaining data and close the temp file writer
-            FlushRows(0);
+            flushRows(0, true);
+
             _writer.Close();
             return _writer.GetWorksheetXmlInputStream();
         }

ooxml/XSSF/Streaming/SXSSFWorkbook.cs

@@ -467,7 +467,7 @@ private void InjectData(FileInfo zipfile, Stream outStream)
                         }
                         else
                         {
-                            CopyStream(inputStream, zos);
+                            inputStream.CopyTo(zos);
                         }
                         inputStream.Close();
                     }
@@ -483,17 +483,6 @@ private void InjectData(FileInfo zipfile, Stream outStream)
             }
         }
 
-        private static void CopyStream(Stream inputStream, Stream outputStream)
-        {
-            var chunk = new byte[1024];
-            int count;
-
-            while ((count = inputStream.Read(chunk, 0, chunk.Length)) > 0)
-            {
-                outputStream.Write(chunk, 0, count);
-            }
-        }
-
         private static void CopyStreamAndInjectWorksheet(Stream inputStream, Stream outputStream, Stream worksheetData)
         {
             StreamReader inReader = new StreamReader(inputStream, Encoding.UTF8);
@@ -604,7 +593,7 @@ private static void CopyStreamAndInjectWorksheet(Stream inputStream, Stream outp
                 outWriter.Flush();
             }
             //Copy the worksheet data to "out".
-            CopyStream(worksheetData, outputStream);
+            worksheetData.CopyTo(outputStream);
             outWriter.Write("</sheetData>");
             outWriter.Flush();
             //Copy the rest of "in" to "out".