How to debug Spring MVC Application

How can we debug Spring Application or Spring MVC Application?
I have commons-logging.jar. But don't know how to use it?
Or is there any other alternative to step through to debug my application by setting breakpoints.

I am using Spring Tool Suite.
Please help.

STS is built on Eclipse so the debugger works the same way. You can see this tutorial for an overview

http://www.vogella.com/articles/EclipseDebugging/article.html

The main difference is you may not be running a java application but rather a web app. To start TC-server click the 'Start the server in debug mode' button. It looks like a bug and is right next to the green play button in the servers tab in the lower left corner of the screen.