java

The resources on the website are pretty good, check out in particular the documentation and tutorials and online training sections.

I think I know probably the absolutely best link where you can learn everything at once without much effort and its called http://www.google.com

Serious, I am sorry for this sarcastic post but this is an awful question. If you like specialized information, thats great and everybody will help you or point out something but an overall question for studying a tutorial overflowing language like Java is in my opinion not the best way to start a thread.
The problem is, there is no BEST link for studying Java. There are many MANY links, one will find a theoretical approach more fitting the other a more practical... it just depends!

The Java Site links already post are probably the best direct tutorials. http://www.exampledepot.com is a practical class approach. Very good for looking up things.
Other sites would be to explicitly google for "studying java" or "java tutorials" and you will be overwhelmed with good tuts.
Other resources would be books (top rated at amazon) like "Thinking in Java", "Headfirst Java", "Core Java" and "Java in a Nutshell". If you already know C++, there are some books that try teaching Java by comparing it to C++, so try these!


I am really sorry but that was needless post in my opinion as this very own forum has enough of such already (e.g. http://www.gamedev.net/community/forums/topic.asp?topic_id=357994&whichpage=1).