BAEL-5201 Finding the Last Row in an Excel Spreadsheet From Java (#11873)

apache-poi-2/src/test/java/com/baeldung/poi/excel/lastrow/LastRowUnitTest.java

@@ -0,0 +1,67 @@
+package com.baeldung.poi.excel.lastrow;
+
+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.xssf.usermodel.XSSFWorkbook;
+import org.junit.Before;
+import org.junit.Test;
+
+import java.io.IOException;
+import java.net.URISyntaxException;
+import java.nio.file.Paths;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+public class LastRowUnitTest {
+    private static final String FILE_NAME = "lastRowTest.xlsx";
+    private String fileLocation;
+
+    @Before
+    public void setup() throws URISyntaxException {
+        fileLocation = Paths.get(ClassLoader.getSystemResource(FILE_NAME).toURI()).toString();
+    }
+
+    @Test
+    public void givenExampleGrid_whenGetRow_thenReturnRowObjectIfModified() throws IOException {
+        Workbook workbook = new XSSFWorkbook(fileLocation);
+        Sheet sheet = workbook.getSheetAt(0);
+
+        assertEquals(7, sheet.getLastRowNum());
+        assertEquals(6, sheet.getPhysicalNumberOfRows());
+
+        assertNotNull(sheet.getRow(0));
+        assertNotNull(sheet.getRow(1));
+        assertNotNull(sheet.getRow(2));
+        assertNotNull(sheet.getRow(3));
+        assertNull(sheet.getRow(4));
+        assertNull(sheet.getRow(5));
+        assertNotNull(sheet.getRow(6));
+        assertNotNull(sheet.getRow(7));
+        assertNull(sheet.getRow(8));
+
+        assertSame(sheet.getRow(7), getLastRowFromSheet(sheet));
+    }
+
+    @Test
+    public void givenEmptySheet_whenGetRow_thenReturnNull() throws IOException {
+        Workbook workbook = new XSSFWorkbook(fileLocation);
+        Sheet sheet = workbook.getSheetAt(1);
+
+        assertEquals(-1, sheet.getLastRowNum());
+        assertEquals(0, sheet.getPhysicalNumberOfRows());
+
+        assertNull(sheet.getRow(0));
+
+        assertSame(sheet.getRow(0), getLastRowFromSheet(sheet));
+    }
+
+    public static Row getLastRowFromSheet(Sheet sheet) {
+        Row lastRow = null;
+        int lastRowNum = sheet.getLastRowNum();
+        if (lastRowNum >= 0) {
+            lastRow = sheet.getRow(lastRowNum);
+        }
+        return lastRow;
+    }
+}