BAEL-7278 Modify the code based on the feedback

pdf-2/src/main/java/com/baeldung/exceltopdf/ExcelToPDFConverter.java

@@ -3,10 +3,13 @@ package com.baeldung.exceltopdf;
 import java.io.FileInputStream;
 import java.io.FileOutputStream;
 import java.io.IOException;
+import java.math.BigDecimal;
 import java.util.Iterator;
 
 import org.apache.poi.ss.usermodel.CellStyle;
+import org.apache.poi.ss.usermodel.HorizontalAlignment;
 import org.apache.poi.ss.usermodel.IndexedColors;
+import org.apache.poi.ss.usermodel.VerticalAlignment;
 import org.apache.poi.xssf.usermodel.XSSFColor;
 import org.apache.poi.xssf.usermodel.XSSFFont;
 import org.apache.poi.xssf.usermodel.XSSFSheet;
@@ -14,31 +17,40 @@ import org.apache.poi.xssf.usermodel.XSSFWorkbook;
 import org.apache.poi.ss.usermodel.CellType;
 import org.apache.poi.ss.usermodel.Row;
 import org.apache.poi.ss.usermodel.Cell;
+
 import com.itextpdf.text.BaseColor;
 import com.itextpdf.text.Document;
 import com.itextpdf.text.DocumentException;
 import com.itextpdf.text.Element;
 import com.itextpdf.text.Font;
+import com.itextpdf.text.FontFactory;
 import com.itextpdf.text.Paragraph;
 import com.itextpdf.text.Phrase;
 import com.itextpdf.text.pdf.PdfPCell;
 import com.itextpdf.text.pdf.PdfPTable;
 import com.itextpdf.text.pdf.PdfWriter;
 
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+
 public class ExcelToPDFConverter {
 
+    private static final Logger logger = LogManager.getLogger(ExcelToPDFConverter.class);
+
     public static XSSFWorkbook readExcelFile(String excelFilePath) throws IOException {
         FileInputStream inputStream = new FileInputStream(excelFilePath);
         XSSFWorkbook workbook = new XSSFWorkbook(inputStream);
         inputStream.close();
         return workbook;
     }
+
     private static Document createPDFDocument(String pdfFilePath) throws IOException, DocumentException {
         Document document = new Document();
         PdfWriter.getInstance(document, new FileOutputStream(pdfFilePath));
         document.open();
         return document;
     }
+
     public static void convertExcelToPDF(String excelFilePath, String pdfFilePath) throws IOException, DocumentException {
         XSSFWorkbook workbook = readExcelFile(excelFilePath);
         Document document = createPDFDocument(pdfFilePath);
@@ -48,6 +60,7 @@ public class ExcelToPDFConverter {
 
             // Add header with sheet name as title
             Paragraph title = new Paragraph(worksheet.getSheetName(), new Font(Font.FontFamily.HELVETICA, 18, Font.BOLD));
+            title.setSpacingAfter(20f);
             title.setAlignment(Element.ALIGN_CENTER);
             document.add(title);
 
@@ -63,7 +76,8 @@ public class ExcelToPDFConverter {
     }
 
     private static void createAndAddTable(XSSFSheet worksheet, Document document) throws DocumentException, IOException {
-        PdfPTable table = new PdfPTable(worksheet.getRow(0).getPhysicalNumberOfCells());
+        PdfPTable table = new PdfPTable(worksheet.getRow(0)
+            .getPhysicalNumberOfCells());
         table.setWidthPercentage(100);
         addTableHeader(worksheet, table);
         addTableData(worksheet, table);
@@ -74,9 +88,27 @@ public class ExcelToPDFConverter {
         Row headerRow = worksheet.getRow(0);
         for (int i = 0; i < headerRow.getPhysicalNumberOfCells(); i++) {
             Cell cell = headerRow.getCell(i);
-            String headerText = cell.getCellType() == CellType.STRING ? cell.getStringCellValue() : String.valueOf(cell.getNumericCellValue());
+
+            String headerText;
+            switch (cell.getCellType()) {
+            case STRING:
+                headerText = cell.getStringCellValue();
+                break;
+            case NUMERIC:
+                headerText = String.valueOf(BigDecimal.valueOf(cell.getNumericCellValue()));
+                break;
+            case BLANK:
+                headerText = ""; // or null
+                break;
+            default:
+                logger.warn("Unsupported cell type: {}", cell.getCellType());
+                headerText = ""; // or throw an exception
+                break;
+            }
+
             PdfPCell headerCell = new PdfPCell(new Phrase(headerText, getCellStyle(cell)));
-            headerCell.setHorizontalAlignment(Element.ALIGN_CENTER);
+            setBackgroundColor(cell, headerCell);
+            setCellAlignment(cell, headerCell);
             table.addCell(headerCell);
         }
     }
@@ -91,7 +123,6 @@ public class ExcelToPDFConverter {
             for (int i = 0; i < row.getPhysicalNumberOfCells(); i++) {
                 Cell cell = row.getCell(i);
                 String cellValue;
-                if (cell != null) {
                 if (cell.getCellType() == CellType.STRING) {
                     cellValue = cell.getStringCellValue();
                 } else if (cell.getCellType() == CellType.NUMERIC) {
@@ -99,10 +130,15 @@ public class ExcelToPDFConverter {
                 } else {
                     cellValue = "";
                 }
-                } else {
-                    cellValue = "";
-                }
                 PdfPCell cellPdf = new PdfPCell(new Phrase(cellValue, getCellStyle(cell)));
+                setBackgroundColor(cell, cellPdf);
+                setCellAlignment(cell, cellPdf);
+                table.addCell(cellPdf);
+            }
+        }
+    }
+
+    private static void setBackgroundColor(Cell cell, PdfPCell cellPdf) {
         // Set background color
         short bgColorIndex = cell.getCellStyle()
             .getFillForegroundColor();
@@ -116,17 +152,52 @@ public class ExcelToPDFConverter {
                 }
             }
         }
-
-                cellPdf.setHorizontalAlignment(Element.ALIGN_CENTER);
-                table.addCell(cellPdf);
     }
+
+    private static void setCellAlignment(Cell cell, PdfPCell cellPdf) {
+        CellStyle cellStyle = cell.getCellStyle();
+
+        HorizontalAlignment horizontalAlignment = cellStyle.getAlignment();
+        VerticalAlignment verticalAlignment = cellStyle.getVerticalAlignment();
+
+        switch (horizontalAlignment) {
+        case LEFT:
+            cellPdf.setHorizontalAlignment(Element.ALIGN_LEFT);
+            break;
+        case CENTER:
+            cellPdf.setHorizontalAlignment(Element.ALIGN_CENTER);
+            break;
+        case JUSTIFY:
+        case FILL:
+            cellPdf.setVerticalAlignment(Element.ALIGN_JUSTIFIED);
+            break;
+        case RIGHT:
+            cellPdf.setHorizontalAlignment(Element.ALIGN_RIGHT);
+            break;
+        }
+
+        switch (verticalAlignment) {
+        case TOP:
+            cellPdf.setVerticalAlignment(Element.ALIGN_TOP);
+            break;
+        case CENTER:
+            cellPdf.setVerticalAlignment(Element.ALIGN_MIDDLE);
+            break;
+        case JUSTIFY:
+            cellPdf.setVerticalAlignment(Element.ALIGN_JUSTIFIED);
+            break;
+        case BOTTOM:
+            cellPdf.setVerticalAlignment(Element.ALIGN_BOTTOM);
+            break;
         }
     }
 
     private static Font getCellStyle(Cell cell) throws DocumentException, IOException {
-        Font font = new Font(Font.FontFamily.HELVETICA, 12);
+        Font font = new Font();
         CellStyle cellStyle = cell.getCellStyle();
-        org.apache.poi.ss.usermodel.Font cellFont = cell.getSheet().getWorkbook().getFontAt(cellStyle.getFontIndexAsInt());
+        org.apache.poi.ss.usermodel.Font cellFont = cell.getSheet()
+            .getWorkbook()
+            .getFontAt(cellStyle.getFontIndexAsInt());
 
         short fontColorIndex = cellFont.getColor();
         if (fontColorIndex != IndexedColors.AUTOMATIC.getIndex() && cellFont instanceof XSSFFont) {
@@ -138,6 +209,7 @@ public class ExcelToPDFConverter {
                 }
             }
         }
+
         if (cellFont.getItalic()) {
             font.setStyle(Font.ITALIC);
         }
@@ -156,6 +228,16 @@ public class ExcelToPDFConverter {
         if (cellFont.getBold()) {
             font.setStyle(Font.BOLD);
         }
+
+        String fontName = cellFont.getFontName();
+        if (FontFactory.isRegistered(fontName)) {
+            font.setFamily(fontName); // Use extracted font family if supported by iText
+        } else {
+            logger.warn("Unsupported font type: {}", fontName);
+            // - Use a fallback font (e.g., Helvetica)
+            font.setFamily("Helvetica");
+        }
+
         return font;
     }