"b. venkata ravi" wrote:
> 
>    Present I am using jsdk2.0 software. I am getting compilation errors
> regularly in chat servelet programs. I want jsdk2.2 software,. where I can
> get that software. Please give the site address, and process of download.

All Java SDK or a Java libraries are at http://java.sun.com/products

Here's another good resource for servlet information:
http://www.purpletech.com/servlet-faq/