TL:DR; Java package/API to send and receive faxes.
Java package/API to send and receive faxes. It can be used to send and receive faxes from your java applications to any group 3 facsimile machine. It requires a class 1 faxmodem, it can fax images, text, html and pdf files. The source code is available.
Jep is a Java library for parsing and evaluating mathematical expressions. With this package you can allow your users to enter an arbitrary formula as a string, and instantly evaluate it. Jep supports user defined variables, constants, and functions.
Aspose.Pdf for JasperReports is a Java component to export reports from JasperReports and JasperServer to PDF format. It allows you to convert .jrxml reports to PDF; supports all reporting features and many chart layouts as well.
License4J is a pure Java library for creating and validating licenses. The key concept is features of a license. You can easily add any feature to your license file, i.e. name of the product, version, expiry date, number of executable instances, etc.