pdf generator Itext and JAX-RS - itext

Question

I would like to know how to create class that generates a pdf using Itext and send it over to a web browser using JAX-RS using the #GET and #Produces annotation.

Answer 1

Below is my solution, simplified to fit here. I'm using JDK 8 lambdas in the generate method, if you can't, just return an anonymous inner class implementing StreamOutput.
#Path("pdf")
#Produces(ContractResource.APPLICATION_PDF)
public class PdfResource {
public static final String APPLICATION_PDF = "application/pdf";
#GET
#Path("generate")
public StreamingOutput generate() {
return output -> {
try {
generate(output);
} catch (DocumentException e) {
throw new IOException("error generating PDF", e);
}
};
}
private void generate(OutputStream outputStream) throws IOException, DocumentException {
Document document = new Document();
PdfWriter.getInstance(document, outputStream);
document.open();
document.add(new Paragraph("Test"));
document.close();
}
}

Answer 2

Mock solution that serves PDF file on browser without storing a file on the server side with JAX-RS and IText 5 Legacy.
#Path("download/pdf")
public class MockPdfService{
#GET
#Path("/mockFile")
public Response downloadMockFile() {
try {
// mock document creation
com.itextpdf.text.Document document = new Document();
ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
com.itextpdf.text.pdf.PdfWriter.getInstance(document, byteArrayOutputStream);
document.open();
document.add(new Chunk("Sample text"));
document.close();
// mock response
return Response.ok(byteArrayOutputStream.toByteArray(), MediaType.APPLICATION_OCTET_STREAM)
.header("content-disposition", "attachment; filename = mockFile.pdf")
.build();
} catch (DocumentException ignored) {
return Response.serverError().build();
}
}
}