I have searching in search Engine regarding convert dex file to jar file but I got failure to find dex2jar file in code.Google.com
I have getting basic idea from here.>
Extract dex2jar-0.0.9.8.zip and copy classes.dex, which is extarcted from apk file to that folder and use below command instead of dex2jar classes.dex because it is deprecated
./d2j-dex2jar.sh classes.dex