tcpdump prints a description of the contents of packets on a network interface which match a given boolean expression. It can also be run with the -w flag, which causes it to save the packet data to a file for later analysis, and/or with the -r flag, which causes it to read from a saved packet file rather than to read packets from a network interface. In all cases, only packets which match the expression will be processed by tcpdump. tcpdump logs more than just TCP, IP, or ethernet packets, but has a whole suite of decoders, including ones for USB.
foma is a compiler, programming language, and C library for constructing finite-state automata and transducers for various uses. It has specific support for many natural language processing applications such as producing morphological analyzers. Although NLP applications are probably the main use of foma, it is sufficiently generic to use for a large number of purposes. It comes with an xfst-compatible interface and regular expression language. The library contains efficient implementations of all classical automata/transducer algorithms: determinization, minimization, epsilon-removal, composition, and boolean operations. More advanced construction methods are also available: context restriction, quotients, first-order regular logic, transducers from replacement rules, etc.
jPDFAssemble is a Java library to assemble PDF files. It can combine, merge, or split PDF documents, and allows the addition or manipulation of bookmarks. It can save resulting documents to the local filesystem or to an output stream, to be able to serve the documents directly to a client browser when working within a J2EE server. jPDFAssemble is built on top of Qoppa's proprietary PDF technology, so you do not have to install any third party software or drivers. It is also 100% Java, so it is completely platform-independent.
jPDFFields is a Java library for working with interactive PDF forms in both AcroForm and XFA formats. It allows your application to get and set field values, and can import and export to the FDF, XFDF, and XDP formats. It can also "flatten" fields in a document. (Flattening is the process of merging the fields into the PDF content layer so the information is retained, but as static PDF content.) jPDFFields is built on top of Qoppa's proprietary PDF technology, so it is 100% Java and does not require any third party software or drivers.