PD4ML PDF XFDF

PD4ML PDF XFDF moves review comments and form data in and out of existing PDF files. XFDF (ISO 19444-1) is an XML format that carries a PDF's annotations and form field values without the rest of the document. The com.pd4ml.pdf.xfdf package exports a PDF's markup annotations and AcroForm field values to an XFDF document, and imports an XFDF document's annotations and field values back into a PDF. The same operations are available from the command line with pd4xfdfcli.

What you can do with it

• Export every markup annotation and every non-signature form field value of a PDF to XFDF, from a byte[], File or InputStream, with XfdfExporter.export(...).
• Import an XFDF file into a PDF with XfdfImporter.importInto(...): annotations are added as new PDF annotations; field values update fields that already exist in the PDF's /AcroForm. A field name that matches nothing is reported in Result.getFieldsNotFound().
• Update annotations in place with Options.updateIfExists(true): an annotation whose name (/NM) matches one already in the PDF is updated instead of added a second time.
• Round-trip all XFDF annotation types: Text, Link, FreeText, Line, Square, Circle, Polygon, PolyLine, Highlight, Underline, Squiggly, StrikeOut, Stamp, Caret, Ink, Popup, FileAttachment, Sound and Redact.
• Filter export or import with Options.types(String) (annotation types such as square, field types Tx/Btn/Ch) and Options.ids(String) (annotation /NM values, fully-qualified field names).
• Read encrypted PDFs with the user or owner password, and optimize or encrypt the imported PDF with Options.optimizeOutput(true) and Options.encryptOutput(...).
• Keep tagged PDFs tagged: in a PDF that has a structure tree, each newly added annotation gets its own structure element.
• Work with XFDF without a PDF: XfdfReader.read(byte[]) parses XFDF into a plain XfdfDocument model of XfdfAnnotation and XfdfField objects.

Quick start

Export the annotations and field values of one PDF and import them into another (both methods throw XfdfException):

import com.pd4ml.pdf.xfdf.XfdfExporter;
import com.pd4ml.pdf.xfdf.XfdfImporter;
import java.nio.file.Files;
import java.nio.file.Paths;

byte[] reviewed = Files.readAllBytes(Paths.get("reviewed.pdf"));
byte[] xfdf = XfdfExporter.export(reviewed);

byte[] original = Files.readAllBytes(Paths.get("original.pdf"));
XfdfImporter.Options options = new XfdfImporter.Options()
        .updateIfExists(true);
XfdfImporter.Result result = XfdfImporter.importInto(original, xfdf, options);
Files.write(Paths.get("annotated.pdf"), result.getPdf());

System.out.println(result.getAnnotationsAdded() + " added, "
        + result.getFieldsUpdated() + " field(s) updated");

The same from the command line:

java -cp pd4ml.jar com.pd4ml.pdf.xfdf.cli.Pd4XfdfCli export --in=reviewed.pdf --out=comments.xfdf
java -cp pd4ml.jar com.pd4ml.pdf.xfdf.cli.Pd4XfdfCli import --in=original.pdf --xfdf=comments.xfdf --out=annotated.pdf --update-if-exists

When to use it

Use PD4ML PDF XFDF when the data you need to move is annotations or form field values. It does not create new form fields and does not regenerate appearance streams. PD4ML's HTML converter turns <input>, <select> and <textarea> elements into AcroForm fields, so XFDF can fill or read the fields of a PDF that PD4ML produced.

In this section

• PD4ML XFDF API - Programmer's Manual - architecture, the export and import API, annotation type coverage, form field rules, filtering, encryption, error messages and tagged PDFs.
• Examples - eight runnable use-case classes in the pd4ml-examples repository, from a basic round trip to error handling.
• pd4xfdfcli Reference - export and import modes, all flags, exit codes and troubleshooting.
• Javadoc - API reference for com.pd4ml.pdf.xfdf.