Why does this FileOutputStream give a NullPointerException?

Why does this FileOutputStream give a NullPointerException?

References

Reference NO 1

http://stackoverflow.com/questions/15194471/why-does-this-fileoutputstream-give-a-nullpointerexception

Reference NO 2

http://stackoverflow.com/questions/17949632/why-does-getelementsbytag-throw-nullpointerexception

Reference NO 3

http://android.bigresource.com/Android-Why-does-this-phone-File-Output-Stream-throw-a-Null-Pointer-Exception--jMQ1eEqQZ.html

Reference NO 4

http://www.greenfoot.org/topics/15

Reference NO 5

http://gatkforums.broadinstitute.org/discussion/2378/how-to-use-the-variantcontextwriter-nullpointerexception-exception-up-on-closing

Reference NO 6

http://www.daniweb.com/software-development/java/threads/200717/exception-in-thread-quotmainquot-java.lang.nullpointerexception

Reference NO 7

http://www.coderanch.com/t/508321/java/java/Facing-null-pointer-exception-static

Reference NO 8

http://itext-general.2136553.n4.nabble.com/java-lang-NullPointerException-on-writer-PdfWriter-getInstance-document-new-FileOutputStream-outFile-td2146773.html