Need help to create the PDF layout as depicted in image using java and itext library

II am beginner with itext, I have created simple layouts but the below layout in attached image is bit complex to create, but unable to create the layout using iText.

the attached image is just for the sample, entire data is fake, I have all the required data in DTO.

I created method which will generate table, but as we see the rows and columns are not uniform, and here I stuck

 private static void createTable(Section subCatPart)
        throws BadElementException {
    PdfPTable table = new PdfPTable(3);

    // t.setBorderColor(BaseColor.GRAY);
    // t.setPadding(4);
    // t.setSpacing(4);
    // t.setBorderWidth(1);

    PdfPCell c1 = new PdfPCell(new Phrase("Table Header 1"));
    c1.setHorizontalAlignment(Element.ALIGN_CENTER);
    table.addCell(c1);

    c1 = new PdfPCell(new Phrase("Table Header 2"));
    c1.setHorizontalAlignment(Element.ALIGN_CENTER);
    table.addCell(c1);

    c1 = new PdfPCell(new Phrase("Table Header 3"));
    c1.setHorizontalAlignment(Element.ALIGN_CENTER);
    table.addCell(c1);
    table.setHeaderRows(1);

    table.addCell("1.0");
    table.addCell("1.1");
    table.addCell("1.2");
    table.addCell("2.1");
    table.addCell("2.2");
    table.addCell("2.3");

    subCatPart.add(table);

}