PDF Genaration

http://www.vogella.com/articles/JavaPDF/article.html

http://viralpatel.net/blogs/generate-pdf-file-in-java-using-itext-jar/

http://www.java4s.com/core-java/creating-pdf-with-java-and-itext-generating-pdf-using-java-example/

Jasper report

find ireport tool from this site:http://sourceforge.net/projects/ireport/files/iReport/iReport-5.0.0/

Installation and execution process:http://www.opus-college.net/devcorner/iReport-Ultimate-Guide-3.pdf
simply follow this sites

Explaination of SQL Joins

How to Get Source code files from android APK file

Just follow this tutorial

http://arunkumarpd.blogspot.in/2013/02/trick-to-get-source-code-from-apk-file.html