Hi Gopu,
We actully ease our work/effort by adding different jar files. Using it we can do it more effectively. For example, In your project you need to draw different types of charts. To achieve this, we can use some already made classes and packed into a jar(bottle
)
JFree Chart. Now you need to use that jar to draw different graphs.
And ojdbc14.jar is used to connect to oracle database.
You can download the source code also of particular API and see how actually particular thing is done and if you wish and they permit you can modify them also.
[ May 26, 2008: Message edited by: Vishal Pandya ]