iText
iText is a library that allows you to generate PDF files on the fly. The iText classes are very useful for people who need to generate read-only, platform independent documents containing text, lists, tables and images. The library is especially useful in combination with Java(TM) technology-based Servlets: The look and feel of HTML is browser dependent; with iText and PDF you can control exactly how your servlet's output will look.
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License
Mozilla Public License