Recently I learnt java as a crash course in a private institue they covered me core and advanced core concepts in java for the version 1.6. Since the lastest version is java 1.7, so which book I should follow for my further improvements to become an ideal Java programmer.

introduction to java programming by liang

E- balaguruswamy is the best for java. And black book is also..

The improvements in 1.7 are no big deal over 1.6, and many corporates take forever to update, so I wouldn't worry about that. If you're happy with the core concepts I would recommend writing as much code as possible and getting feedback (eg from here) rather than just reading about it.