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Home » Newsletter » May 2010

By V. Subhash

There are two ways for creating PDF file attachments. One is to create a document-level file attachment. The other is to create a file attachment annotation.

File Attachment Annotations

Like all annotations, file attachment annotations are bound to a page. A viewer application, such as Adobe Reader, will use a paperclip, tag, graph or pushpin icon to display a file attachment annotation on a page . When users click these icons, the viewer application will show a prompt and offer to launch or save the embedded file.

Here is the code to create a page-level PDF file attachment.

public static void main(String[] args)
   throws IOException, PdfException  {

    // Create a file attachment annotation and set its properties
    PdfFileAttachmentAnnot fa =
        new PdfFileAttachmentAnnot(10,10,Color.RED);
    fa.setIcon(PdfFileAttachmentAnnot.ICON_PAPERCLIP);
    fa.setTitle("PDF File Attachments Demo");
    fa.setSubject("Embed file using a file attachment annotation");
    fa.setContents("Double-click the icon for the file attachment");
    fa.setFilePath("sample_file.txt");
    fa.setRect(10,10,20,40);


    // Add an optional popup window for the annotation
    // Note: A file attachment annotation does not usually 
    // have a regular popup window.
    PdfPopUpAnnot popup = new PdfPopUpAnnot();
    popup.setRect(40,80,170,120);
    fa.setPopup(popup, flase);

    // Open a PDF document for editing 
    PdfReader reader =
        PdfReader.fileReader(
            "sample_doc.pdf", // Input file
            "sample_doc_with_attachment_annotation.pdf"); // Output file
    PdfDocument doc = new PdfDocument(reader);

    // Add file attachment to page #1
    doc.addAnnotation(fa,1);
    
    doc.setOpenAfterSave(true);

    // Make viewer applications show attachments panel  
    doc.setPageMode(PdfPageMode.USEATTACHMENTS);
 
    // Save file and clean up
    doc.write();
    reader.dispose();
}

Document-Level Attachments

These attachments are not bound to a page. They are document-level resources in a PDF document. A viewer application such as Adobe Reader will show these files in a special attachments panel.*

public static void main(String[] args) 
  throws IOException, PdfException  {
    // Open a PDF document for editing
    PdfReader reader = 
        PdfReader.fileReader(
            "sample_doc.pdf", // Input file 
            "sample_doc_with_document_level_attachment.pdf"); // Output file
    PdfDocument doc = new PdfDocument(reader);
    
    // Add file attachment
    doc.attachDocument("sample_file.txt");

    doc.setOpenAfterSave(true);

    // Make viewer applications show attachments panel  
    doc.setPageMode(PdfPageMode.USEATTACHMENTS);
 
    // Save file and clean up
    doc.write();
    reader.dispose();
}

* - Please note that a file embedded using a file attachment annotation will also be displayed in the attachments panel.