Hi Raja,
You are better off asking this question in the JavaRanch
Linux / UNIX forum - there are likely to be more people there who will know the answer to your question.
From memory, what you download is a self extracting shell script. Run the following commands on it:
(Obviously use the name of the file you downloaded).
That will display the license agreement. When you have read the license agreement, you will be asked to agree to it. Type "yes" and it will extract the real RPM file.
You can then install it using the standard "rpm -i <rpm filename>" command.
I have moving this to the Linux/Unix forum. You can follow up on it here.
Regards, Andrew