Java pdfbox：将pdf转换为图像时如何解决字体(STSongLight)问题

我正在使用pdfbox 2.0.26将pdf转换为图像.Maven依赖项如下所示.

        <dependency>
            <groupId>org.apache.pdfbox</groupId>
            <artifactId>fontbox</artifactId>
            <version>2.0.26</version>
        </dependency>

        <dependency>
            <groupId>org.apache.pdfbox</groupId>
            <artifactId>pdfbox</artifactId>
            <version>2.0.26</version>
        </dependency>

我写的程序就像

        FileInputStream fin = new FileInputStream("/path/to/sample.pdf");
        try(final PDDocument doc = PDDocument.load(fin)){

            PDFRenderer pdfRenderer = new PDFRenderer((doc));

            BufferedImage bim = pdfRenderer.renderImageWithDPI(0, 300, ImageType.RGB);
            File myObj = new File("/path/to/sample.png");
            FileOutputStream fos = new FileOutputStream(myObj);
            ImageIOUtil.writeImage(bim, "png", fos);
            fin.close();
            fos.close();

        } catch (IOException e) {
            System.out.println("error");
        }

它在我的MacOS上运行得很好(尽管图像中的字体与PDF中的字体不同)，但当我在Linux服务器上运行它时，中文字符会丢失.

The source PDF file can be found here the source file. I detected the font using adobe reader, the result are pasted as following.

The resulting image file is like:

我该怎么做才能解决这个问题呢？谢谢