This PR is related to BAEL-6922 (#16171)

* Update pom.xml

* Add files via upload

* This commit is related to BAEL-6922

This commit aims to add a test class named ExcelToJsonUnitTest that provides ways to convert Excel to JSON in Java.

* Update ExcelToJsonUnitTest.java

* Update ExcelToJsonUnitTest.java

json-modules/json-conversion/pom.xml

@@ -29,6 +29,11 @@
             <artifactId>jackson-databind</artifactId>
             <version>${jackson.version}</version>
         </dependency>
+        <dependency>
+            <groupId>org.apache.poi</groupId>
+            <artifactId>poi-ooxml</artifactId>
+            <version>5.2.3</version>
+        </dependency>
         <dependency>
             <groupId>com.google.guava</groupId>
             <artifactId>guava</artifactId>

json-modules/json-conversion/src/test/java/com/baeldung/exceltojson/ExcelToJsonUnitTest.java

@@ -0,0 +1,84 @@
+package com.baeldung.exceltojson;
+
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import org.apache.poi.ss.usermodel.*;
+import org.apache.poi.xssf.usermodel.XSSFWorkbook;
+import org.json.JSONArray;
+import org.junit.Test;
+
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Objects;
+
+import static org.junit.Assert.assertEquals;
+
+public class ExcelToJsonUnitTest {
+    public static String filePath = Objects.requireNonNull(ExcelToJsonUnitTest.class.getClassLoader().getResource("Book1.xlsx")).getFile();
+    public String expectedJson = "[[\"C1\",\"C2\",\"C3\",\"C4\",\"C5\"]," +
+            "[\"1.0\",\"2.0\",\"3.0\",\"4.0\",\"5.0\"]," +
+            "[\"1.0\",\"2.0\",\"3.0\",\"4.0\",\"5.0\"]," +
+            "[\"1.0\",\"2.0\",\"3.0\",\"4.0\",\"5.0\"]," +
+            "[\"1.0\",\"2.0\",\"3.0\",\"4.0\",\"5.0\"]]";
+    private Workbook workbook;
+    private Sheet sheet;
+    private InputStream inputStream;
+
+    public ExcelToJsonUnitTest() throws IOException {
+        inputStream = new FileInputStream(filePath);
+        workbook = new XSSFWorkbook(inputStream);
+        sheet = workbook.getSheetAt(0);
+    }
+
+    @Test
+    public void givenExcelFile_whenUsingApachePOIConversion_thenConvertToJson() {
+        JSONArray jsonArray = new JSONArray();
+
+        Row headerRow = sheet.getRow(0);
+        List<String> headers = new ArrayList<>();
+        for (Cell cell : headerRow) {
+            headers.add(cell.toString());
+        }
+        jsonArray.put(headers);
+
+        for (int i = 1; i <= sheet.getLastRowNum(); i++) {
+            Row row = sheet.getRow(i);
+            List<String> rowData = new ArrayList<>();
+            for (Cell cell : row) {
+                rowData.add(cell.toString());
+            }
+            jsonArray.put(rowData);
+        }
+
+        assertEquals(expectedJson, jsonArray.toString());
+    }
+
+    @Test
+    public void givenExcelFile_whenUsingJacksonConversion_thenConvertToJson() throws JsonProcessingException {
+        List<List<String>> data = new ArrayList<>();
+
+        Row headerRow = sheet.getRow(0);
+        List<String> headers = new ArrayList<>();
+        for (Cell cell : headerRow) {
+            headers.add(cell.toString());
+        }
+        data.add(headers);
+
+        for (int i = 1; i <= sheet.getLastRowNum(); i++) {
+            Row row = sheet.getRow(i);
+            List<String> rowData = new ArrayList<>();
+            for (Cell cell : row) {
+                rowData.add(cell.toString());
+            }
+            data.add(rowData);
+        }
+
+        ObjectMapper objectMapper = new ObjectMapper();
+        String json = objectMapper.writeValueAsString(data);
+
+        assertEquals(expectedJson, json);
+    }
+}