Rathi, I think ant is overkill for this. When you do larger projects, it is something to look into. (When the time comes we have an Ant forum below.)
Creating a batch file is a good idea. Create a file with the extension .bat. Open the file in notepad and type in the commands you put in your initial post. Then you can double click and run the batch file.
Adeel raises a good point that you will likely be using the same path/classpath settings repeatedly. You can set these under the control panel in Windows and the login script in UNIX/Linux.
Now my that project is completed . But in new project I have to use Ant . Can any body explain me this in short . What I know is : Ant is a open source project that help us to build & compile java application .