Example:

Document doc = new Document();

// Insert a structured document tag that prompts the user to enter a date.
// In Microsoft Word, this element is known as a "Date picker content control".
// When we click on the arrow on the right end of this tag in Microsoft Word,
// we will see a pop up in the form of a clickable calendar.
// We can use that popup to select a date that the tag will display.
StructuredDocumentTag sdtDate = new StructuredDocumentTag(doc, SdtType.DATE, MarkupLevel.INLINE);

// Display the date, according to the Saudi Arabian Arabic locale.
sdtDate.setDateDisplayLocale(1025);

// Set the format with which to display the date.
sdtDate.setDateDisplayFormat("dd MMMM, yyyy");
sdtDate.setDateStorageFormat(SdtDateStorageFormat.DATE_TIME);

// Display the date according to the Hijri calendar.
sdtDate.setCalendarType(SdtCalendarType.HIJRI);

// Before the user chooses a date in Microsoft Word, the tag will display the text "Click here to enter a date.".
// According to the tag's calendar, set the "FullDate" property to get the tag to display a default date.
Calendar cal = Calendar.getInstance();
cal.set(1440, 10, 20);
sdtDate.setFullDate(cal.getTime());

DocumentBuilder builder = new DocumentBuilder(doc);
builder.insertNode(sdtDate);

doc.save(getArtifactsDir() + "StructuredDocumentTag.Date.docx");