Java Tutorial/PDF/Print

warn you before printing the document

import java.io.FileOutputStream;
import com.lowagie.text.Document;
import com.lowagie.text.Paragraph;
import com.lowagie.text.pdf.PdfAction;
import com.lowagie.text.pdf.PdfContentByte;
import com.lowagie.text.pdf.PdfDestination;
import com.lowagie.text.pdf.PdfWriter;
public class MainClass {
  public static void main(String[] args) throws Exception {
    Document document = new Document();
    PdfWriter writer = PdfWriter.getInstance(document, new FileOutputStream("2.pdf"));
    document.open();
    document.add(new Paragraph("test."));
    PdfAction copyrightNotice = PdfAction.javaScript(
        "app.alert("Warning: this document is protected by copyright.");\r", writer);
    writer.setAdditionalAction(PdfWriter.WILL_PRINT, copyrightNotice);
    
    document.close();
  }
}