Fix cell value bug

If a cell is numeric the string
value cannot be retrieved directly.

src/main/kotlin/KafkaTopology.kt

@@ -29,6 +29,7 @@ import org.apache.kafka.streams.StreamsBuilder
 import org.apache.kafka.streams.Topology
 import org.apache.kafka.streams.kstream.KStream
 import org.apache.kafka.streams.kstream.Predicate
+import org.apache.poi.ss.usermodel.Cell
 import org.apache.poi.ss.usermodel.CellType
 import org.apache.poi.ss.usermodel.Row
 import org.apache.poi.ss.usermodel.WorkbookFactory
@@ -303,8 +304,8 @@ class KafkaTopology(private val settings: SettingsLoader) {
                     if (count <= headerCount) {
                         if (count == propertyNamesIndex) {
                             propertiesList.addAll(row.map { cell ->
-                                if (cell.stringCellValue.isNotEmpty()) {
-                                    if (cell.stringCellValue.any { char ->
+                                if (retriveCellValue(cell).isNotEmpty()) {
+                                    if (retriveCellValue(cell).any { char ->
                                             invalidPropertyNameCharacters.contains(
                                                 char
                                             )
@@ -314,7 +315,7 @@ class KafkaTopology(private val settings: SettingsLoader) {
                                             "The property in cell ${cell.address} contains one or more invalid characters: $invalidPropertyNameCharacters."
                                         )
                                     } else {
-                                        cell.stringCellValue
+                                        retriveCellValue(cell)
                                     }
                                 } else {
                                     throw InvalidInputException(
@@ -329,7 +330,7 @@ class KafkaTopology(private val settings: SettingsLoader) {
                         val rowIdentifier: String = try {
                             row.getCell(identifierIndex - 1).let { cell ->
                                 if (cell != null) {
-                                    when (val cellValue = cell.stringCellValue) {
+                                    when (val cellValue = retriveCellValue(cell)) {
                                         "" -> {
                                             throw InvalidInputException(
                                                 "CellAddress: $count:$identifierIndex",
@@ -393,18 +394,22 @@ class KafkaTopology(private val settings: SettingsLoader) {
     private fun retrieveCells(row: Row, size: Int): List<String> {
         return (0..size).map { i ->
             val cell = row.getCell(i)
-            if (cell != null) {
-                when (cell.cellType) {
-                    CellType.BLANK -> ""
-                    CellType.BOOLEAN -> cell.booleanCellValue.toString()
-                    CellType._NONE -> ""
-                    CellType.NUMERIC -> cell.numericCellValue.toString()
-                    CellType.STRING -> cell.stringCellValue
-                    CellType.FORMULA -> ""
-                    CellType.ERROR -> ""
-                    else -> ""
-                }
-            } else ""
+            retriveCellValue(cell)
         }
     }
+
+    private fun retriveCellValue(cell: Cell?): String {
+        return if (cell != null) {
+            when (cell.cellType) {
+                CellType.BLANK -> ""
+                CellType.BOOLEAN -> cell.booleanCellValue.toString()
+                CellType._NONE -> ""
+                CellType.NUMERIC -> cell.numericCellValue.toString()
+                CellType.STRING -> cell.stringCellValue
+                CellType.FORMULA -> ""
+                CellType.ERROR -> ""
+                else -> ""
+            }
+        } else ""
+    }
 }