How to convert a PDF to an image
You can install the library manually or use the Maven repository:
To convert the PDF, here it is the code:
PDDocument doc = PDDocument.load("myFile.pdf");
PDPage firstPage = (PDPage) doc.getDocumentCatalog().getAllPages().get(0);
BufferedImage bufferedImage = firstPage.convertToImage();
You can even load the PDF document by a Stream or a Url. You have the first page preview of your PDF file in the BufferdImage variable. Then you can save it into the preferred extension.
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