PDFBox2的Unicode字体书写问题（U + 0053没有字形）

Question

我试图用PDFBox将一些孟加拉文本写成pdf，但是遇到一些问题U + 0053没有字形。我不知道字形。

        File file = new File("xyz.pdf");
        PDDocument document = PDDocument.load(file);
        PDPage page = document.getPage(0);
        PDPageContentStream contentStream = new PDPageContentStream(document, page);
        contentStream.beginText();
        PDFont font = PDType0Font.load(document, BengaliPdfGenerationHelloWorld.class.getResourceAsStream("/textloc/Lohit-Bengali.ttf"),true);
        contentStream.setFont(font,12);
        contentStream.newLineAtOffset();
        contentStream.showText(text);
        contentStream.endText();
        System.out.println("Content added");
        contentStream.close();
        document.save(new File("new.pdf"));

        Exception in thread "main" java.lang.IllegalArgumentException: No glyph for U+0053 (S) in font Lohit-Bengali
            at org.apache.pdfbox.pdmodel.font.PDCIDFontType2.encode(PDCIDFontType2.java:366)
            at org.apache.pdfbox.pdmodel.font.PDType0Font.encode(PDType0Font.java:415)
            at org.apache.pdfbox.pdmodel.font.PDFont.encode(PDFont.java:342)