Searching in PDF and other file formats

http://tika.apache.org/

http://www.programming-free.com/2012/11/simple-word-search-in-pdf-files-using.html

http://www.blog.computergodzilla.com/2012/12/apache-lucene-how-to-index-doc-pdf-and.html

http://www.blog.computergodzilla.com/2012/12/apache-lucene-how-to-parse-texts-from_30.html

http://kalanir.blogspot.sg/2008/07/extracting-text-from-xml-documents-for.html