This article gives you a highlight of important features added in every major Java release. I am sure you will find it interesting.
I am talking about the versions in reverse chronological order (latest first)
Java 8 was released on 18 March 2014. The code name culture is dropped with Java 8 and so no official code name going forward from Java 8.
Code named Dolphin and released on July 28, 2011.
Code named Mustang and released on December 11, 2006.
Code named Tiger and released on September 30, 2004.
Code named Merlin and released on February 6, 2002 (first release under JCP).
Code named Kestrel and released on May 8, 2000.
Code named Playground and released on December 8, 1998.
Codenamed Oak and released on January 23, 1996.