iText：不存在单元格内容短语

Question

当我调用：

时

public class App 
{
public static void main( String[] args )
{
    try {

        TemplateGenerator tg = new TemplateGenerator();
        tg.generateTemplateFile();


    } catch (IOException e) {
        e.printStackTrace();
    } catch (DocumentException e) {
        e.printStackTrace();
    }
}

}

和

public class TemplateGenerator {

    Font cellTitle=null;
public void generateTemplateFile() throws IOException, DocumentException {

        File file = new File(Properties.TEMPLATE_FILE);
        file.getParentFile().mkdirs();
        this.createPdf(Properties.TEMPLATE_FILE);

}

private void createPdf(String dest) throws IOException, DocumentException {
    Document document = new Document();
    PdfWriter.getInstance(document, new FileOutputStream(dest));


    document.setPageSize(this.setupPageSize(Properties.WIDTH_MM,
                                            Properties.HEIGHT_MM));
    document.setMargins(2, 2, 2, 2);

    document.open();

        document.add(buildFrames());

    document.close();
}

private Rectangle setupPageSize(Float width, Float height){
    return new Rectangle(   Utilities.millimetersToPoints(width),
                            Utilities.millimetersToPoints(height));
}

private void setupFonts() throws IOException, DocumentException {
    cellTitle = new Font(Font.FontFamily.HELVETICA, 13, Font.NORMAL, GrayColor.GRAYBLACK);

}

private PdfPTable buildFrames(){
    PdfPTable table;
    table = null;
    try{
        Font fontH1 = new Font(Font.FontFamily.COURIER, 16, Font.NORMAL);

        table = new PdfPTable(1);

        table.addCell(new PdfPCell(new Phrase("aaa",fontH1)));


    }catch (Exception e){
        e.printStackTrace();
    }
    return table;
}

}

我打印了单元格但为空即。没有“aaa”tekst。无论细胞文本没有出现。我想知道什么是错误没有错误。我得到了存储在src / main / resources中的文件，具有664访问权限。有什么问题？