These are the projects used by regain:

• Jakarta Regexp 1.3 (jakarta-regexp-1.3.jar). Allows using regular expressions. See: http://jakarta.apache.org/regexp
• Jakarta Log4j 1.2.11 (log4j-1.2.11.jar). Provides logging. See: http://jakarta.apache.org/log4j
• Jakarta Lucene 1.4.3 (lucene-1.4.3.jar). Contains the core of the search, that is index creation and searching on the index. See http://jakarta.apache.org/lucene
• Apache XML Xerces 2.6.2 (xercesImpl.jar and xml-apis.jar). Provides a parser for reading XML files. See http://xml.apache.org/xerces2-j
• PDFBox 0.7.1 (PDFBox-0.7.1.jar). Reads PDF documents. Only works with Java 1.3 and above. See http://pdfbox.apache.org
• Jakarta POI 3.0 alpha 1 (poi-3.0-alpha1-20050704.jar and poi-scratchpad-3.0-alpha1-20050704.jar). Reads Microsoft Excel and Microsoft Word documents. Unfortunately the reading of Word files is still in an early development stage. See http://jakarta.apache.org/poi
• Jacob 1.8 (jacob.jar und jacob.dll). Allows the access to COM objects from Java. This is used to read Microsoft Office documents, by reading the data directly from the Microsoft Office applications. See http://sourceforge.net/projects/jacob-project
• Jacobgen (jacobgen directory). Code generator for Jacob. Allows a simpler access on COM objects by generating wrapper classes. The used version is a further development of the STZ-IDA, based on version 0.3. See http://www.bigatti.it/projects/jacobgen
• Simple (simple-2.5.3.jar). A very slim Java HTTP server. Used by the desktop search. See also: search mask. See http://simpleweb.sourceforge.net
• JDIC (jdic.jar and tray.dll). A tray icon support. See https://jdic.dev.java.net