com.aspose.words

Example:

Document doc = new Document();

DocumentBuilder builder = new DocumentBuilder(doc);
builder.writeln("Section 1. Hello world!");
builder.insertBreak(BreakType.SECTION_BREAK_NEW_PAGE);

builder.writeln("Section 2. Hello again!");
builder.write("Please enter text here: ");
builder.insertTextInput("TextInput1", TextFormFieldType.REGULAR, "", "Placeholder text", 0);

// Apply write protection to every section in the document.
doc.protect(ProtectionType.ALLOW_ONLY_FORM_FIELDS);

// Turn off write protection for the first section.
doc.getSections().get(0).setProtectedForForms(false);

// In this output document, we will be able to edit the first section freely,
// and we will only be able to edit the contents of the form field in the second section.
doc.save(getArtifactsDir() + "Section.Protect.docx");