转自

public static void convertPdf2Image(String pdfFilepath,String imgFilepath)
        throws IOException
{
    File file;
    file = new File(pdfFilepath);
    String filename = file.getName().substring(0,file.getName().lastIndexOf("."));
    try {
        PDDocument doc = PDDocument.load(file);
        PDFRenderer renderer = new PDFRenderer(doc);
        int pageCount = doc.getNumberOfPages();
        for(int i=0;i<pageCount;i++){
            BufferedImage image = renderer.renderImageWithDPI(i, 150);
            //          BufferedImage image = renderer.renderImage(i, 2.5f);
            ImageIO.write(image, "PNG", new File(imgFilepath+"\\"+filename+".png"));
        }
    } catch (IOException e) {
        e.printStackTrace();
    }

注：需添加fontbox和pdfbox的jar包