PDFOne Java is a 100% Java library for developers to implement PDF based software solutions.
PDFOne Java is a powerful PDF creation and management library for the Java platform. PDFOne Java supports creation, filling and reading of PDF forms, compressing, securing, appending and merging of multiple PDF documents, stamping, building Table of Contents, setting bookmarks, and many more functions that can be performed on PDF documents.
Version 2.0 adds support for specifying a default font for a page, provide viewer component, Printer component and many more features.
OK, so you want to stamp your document. Maybe you need to give reviewers some advice about the document's status or sensitivity. This tip from author Ted Padova demonstrates how to add stamps with the Stamp Tool along with related comments.