worksheet.checkProtectionPassword(String password) 

PdfEncryptionAlgorithm.AES

//Create password security policies
PdfSecurityPolicy securityPolicy = new PdfPasswordSecurityPolicy("", "123456"); 
//Set AES encryption algorithm
securityPolicy.setEncryptionAlgorithm( PdfEncryptionAlgorithm.AES_256); 
//Set document permissions (ownership), default is ForbidAll.
securityPolicy.setDocumentPrivilege(PdfDocumentPrivilege.getForbidAll());
securityPolicy.getDocumentPrivilege().setAllowDegradedPrinting(true);
securityPolicy.getDocumentPrivilege().setAllowModifyAnnotations(true);
securityPolicy.getDocumentPrivilege().setAllowAssembly(true);
securityPolicy.getDocumentPrivilege().setAllowModifyContents(true);
securityPolicy.getDocumentPrivilege().setAllowFillFormFields(true);
securityPolicy.getDocumentPrivilege().setAllowPrint(true);
pdf.encrypt(securityPolicy);

PdfDocument pdf = new PdfDocument();
//Pass the open password to open the PDF document
pdf.loadFromFile(inputFile, "1234"); 
//Decrypt
pdf.decrypt();
pdf.saveToFile(outputFile, FileFormat.PDF);
pdf.dispose();

PdfDocument document=new PdfDocument();
document.loadFromFile("input.pdf");
PdfFormWidget formWidget = (PdfFormWidget)document.getForm();
for (int i = 0; i < formWidget.getFieldsWidget().getCount(); i++)
{
    PdfField field = (PdfField)formWidget.getFieldsWidget().get(i);
    for (PdfFieldWidget widget : (Iterable<? extends PdfFieldWidget>) formWidget.getFieldsWidget())
    {
        if (widget.getName() == "oldName")
        {
            widget.setName("NewName");
        }
    }
}
document.saveToFile("result.pdf",FileFormat.PDF);

paragraph.appendHorizonalLine()

Document doc = new Document();
doc.loadFromFile(inputFile);
doc.saveFontFallbackRuleSettings(outputFile_xml);
doc.loadFontFallbackRuleSettings(outputFile_xml);
doc.saveToFile(outputFile, FileFormat.PDF);

Presentation ppt = new Presentation();
ppt.loadFromFile("input.pptx");
List bytes = ppt.saveToSVGZ();
for (int i = 0; i < bytes.size(); i++) {
FileOutputStream fileOutputStream = new FileOutputStream("slide" + i + ".svgz");
fileOutputStream.write(bytes.get(i));
fileOutputStream.flush();
fileOutputStream.close();
}

Presentation ppt = new Presentation();
ppt.loadFromFile("input.pptx");
List bytes = ppt.saveToSVG(0, 36);
for (int i = 0; i < bytes.size(); i++) {
FileOutputStream fileOutputStream = new FileOutputStream("slide" + (i + 1) + ".svg");
fileOutputStream.write(bytes.get(i));
fileOutputStream.flush();
fileOutputStream.close();
}