Changing the author of an annotation

/*
    This file is part of the iText (R) project.
    Copyright (c) 1998-2023 Apryse Group NV
    Authors: Apryse Software.

    For more information, please contact iText Software at this address:
    sales@itextpdf.com
 */
package com.itextpdf.samples.sandbox.interactive;

import com.itextpdf.kernel.pdf.PdfDocument;
import com.itextpdf.kernel.pdf.PdfWriter;
import com.itextpdf.kernel.pdf.PdfString;
import com.itextpdf.kernel.pdf.PdfReader;
import com.itextpdf.kernel.pdf.annot.PdfAnnotation;

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.util.List;

public class ChangeAuthor {
    public static final String DEST = "./target/sandbox/interactive/change_author.pdf";

    public static final String SRC = "./src/main/resources/pdfs/page229_annotations.pdf";

    public static void main(String[] args) throws IOException {
        File file = new File(DEST);
        file.getParentFile().mkdirs();

        new ChangeAuthor().manipulatePdf(DEST);
    }

    protected void manipulatePdf(String dest) throws IOException {
        PdfDocument pdfDoc = new PdfDocument(new PdfReader(SRC), new PdfWriter(dest));

        List<PdfAnnotation> pageAnnots = pdfDoc.getFirstPage().getAnnotations();
        for (PdfAnnotation annot : pageAnnots) {
            if (annot.getTitle() != null) {
                annot.setTitle(new PdfString("Bruno Lowagie"));
            }
        }

        pdfDoc.close();
    }
}

using System;
using System.Collections.Generic;
using System.IO;
using iText.Kernel.Pdf;
using iText.Kernel.Pdf.Annot;

namespace iText.Samples.Sandbox.Interactive
{
    public class ChangeAuthor
    {
        public static readonly String DEST = "results/sandbox/interactive/change_author.pdf";

        public static readonly String SRC = "../../../resources/pdfs/page229_annotations.pdf";

        public static void Main(String[] args)
        {
            FileInfo file = new FileInfo(DEST);
            file.Directory.Create();

            new ChangeAuthor().ManipulatePdf(DEST);
        }

        protected void ManipulatePdf(String dest)
        {
            PdfDocument pdfDoc = new PdfDocument(new PdfReader(SRC), new PdfWriter(dest));

            IList<PdfAnnotation> pageAnnots = pdfDoc.GetFirstPage().GetAnnotations();
            foreach (PdfAnnotation annot in pageAnnots)
            {
                if (annot.GetTitle() != null)
                {
                    annot.SetTitle(new PdfString("Bruno Lowagie"));
                }
            }

            pdfDoc.Close();
        }
    }
}