Import and Export

Foxit PDF SDK for Android supports importing and exporting annotation data via FDF and XFDF for exchange between documents and systems. The SDK also provides annotation flattening to merge annotations into page content permanently.

FDF and XFDF Formats

Format	Constant	Description
FDF	FDFDoc.e_FDF	Forms Data Format (PDF binary format)
XFDF	FDFDoc.e_XFDF	XML FDF for parsing and integration

FDFDoc core methods:

Method	Description
FDFDoc(int type)	Create empty FDF (FDFDoc.e_FDF or FDFDoc.e_XFDF)
FDFDoc(String path)	Load from file path
getType()	Format type
isEmpty()	Whether empty
saveAs(String filePath)	Save to file

Export Annotations

Export All Annotations

import com.foxit.sdk.fdf.FDFDoc;
import com.foxit.sdk.pdf.PDFDoc;

PDFDoc doc = new PDFDoc("path/to/Sample.pdf");
doc.load(null);

FDFDoc fdfDoc = new FDFDoc(FDFDoc.e_XFDF);
doc.exportToFDF(fdfDoc, PDFDoc.e_Annots, null);
fdfDoc.saveAs("path/to/annotations.xfdf");

NOTE

The second parameter to exportToFDF() is export type; PDFDoc.e_Annots exports annotations. The third parameter is page range (Range); null exports all pages.

Export a Single Annotation

import com.foxit.sdk.fdf.FDFDoc;
import com.foxit.sdk.pdf.PDFDoc;
import com.foxit.sdk.pdf.PDFPage;
import com.foxit.sdk.pdf.annots.Annot;

PDFDoc doc = new PDFDoc("path/to/Sample.pdf");
doc.load(null);
PDFPage page = doc.getPage(0);

Annot annot = page.getAnnot(0);

FDFDoc fdfDoc = new FDFDoc(FDFDoc.e_FDF);
doc.exportAnnotToFDF(annot, fdfDoc);
fdfDoc.saveAs("path/to/single_annot.fdf");

Import Annotations

import com.foxit.sdk.fdf.FDFDoc;
import com.foxit.sdk.pdf.PDFDoc;

PDFDoc doc = new PDFDoc("path/to/Sample.pdf");
doc.load(null);

FDFDoc fdfDoc = new FDFDoc("path/to/annotations.xfdf");

doc.importFromFDF(fdfDoc, PDFDoc.e_Annots, null);

doc.saveAs("path/to/output.pdf", PDFDoc.e_SaveFlagNormal);

Flatten Annotations

Flattening merges annotation appearance into page content and removes the annotation objects.

Flatten All Annotations on a Page

import com.foxit.sdk.pdf.PDFDoc;
import com.foxit.sdk.pdf.PDFPage;

PDFDoc doc = new PDFDoc("path/to/Sample.pdf");
doc.load(null);
PDFPage page = doc.getPage(0);

page.flattenAnnots(true);

doc.saveAs("path/to/flattened.pdf", PDFDoc.e_SaveFlagNormal);

NOTE

flattenAnnots(true) flattens all annotations; false flattens form fields only.

Flatten a Single Annotation

import com.foxit.sdk.pdf.PDFPage;
import com.foxit.sdk.pdf.annots.Annot;

PDFPage page = doc.getPage(0);
Annot annot = page.getAnnot(0);

if (annot != null && !annot.isEmpty()) {
    page.flattenAnnot(annot);
}

Typical Use Cases

Scenario	Approach
Collaborative review — share annotations	Export XFDF, distribute, members import locally
Server-side annotation processing	XFDF (XML) for parsing and storage
Final publish — annotations not editable	Export backup, then flatten all
Archival — consistent rendering	Flatten annotations and form fields