Reuse a font from an existing PDF

JAVA

/**
 * This example is based on an answer given on StackOverflow:
 * http://stackoverflow.com/questions/22186014/itextsharp-re-use-font-embedded-in-acrofield
 */
package sandbox.acroforms;

import com.itextpdf.text.DocumentException;
import com.itextpdf.text.Element;
import com.itextpdf.text.Font;
import com.itextpdf.text.Phrase;
import com.itextpdf.text.pdf.BaseFont;
import com.itextpdf.text.pdf.ColumnText;
import com.itextpdf.text.pdf.PRIndirectReference;
import com.itextpdf.text.pdf.PdfContentByte;
import com.itextpdf.text.pdf.PdfDictionary;
import com.itextpdf.text.pdf.PdfName;
import com.itextpdf.text.pdf.PdfReader;
import com.itextpdf.text.pdf.PdfStamper;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;

import sandbox.WrapToTest;

@WrapToTest
public class ReuseFont {

    public static final String SRC = "resources/pdfs/form.pdf";
    public static final String DEST = "results/acroforms/form_stamped.pdf";
    
    public static void main(String[] args) throws DocumentException, IOException {
        File file = new File(DEST);
        file.getParentFile().mkdirs();
        new ReuseFont().manipulatePdf(SRC, DEST);
    }

    public BaseFont findFontInForm(PdfReader reader, PdfName fontname) {
    	PdfDictionary root = reader.getCatalog();
    	PdfDictionary acroform = root.getAsDict(PdfName.ACROFORM);
    	if (acroform == null) return null;
    	PdfDictionary dr = acroform.getAsDict(PdfName.DR);
    	if (dr == null) return null;
    	PdfDictionary font = dr.getAsDict(PdfName.FONT);
    	if (font == null) return null;
    	for (PdfName key : font.getKeys()) {
    		if (key.equals(fontname)) {
    			return BaseFont.createFont((PRIndirectReference)font.getAsIndirectObject(key));
    		}
    	}
    	return null;
    }
    
    public void manipulatePdf(String src, String dest) throws DocumentException, IOException {
        PdfReader reader = new PdfReader(src);
        PdfStamper stamper = new PdfStamper(reader, new FileOutputStream(dest));
        BaseFont bf = findFontInForm(reader, new PdfName("Calibri"));
        PdfContentByte canvas = stamper.getOverContent(1);
        Phrase phrase = new Phrase("Some text in Calibri", new Font(bf, 13));
        ColumnText.showTextAligned(canvas, Element.ALIGN_LEFT, phrase, 36, 806, 0);
        stamper.close();
    }
}