How to use java .class file to build a reflection program?

I have the following problem: a. Use the ATM class and write your Java Reflection programs to print all Fields, Methods, Constructors, other public and private components. b. Create new instances and invoke components c. Change the accessibility of Private fields and invoke.

I was only provided the .class files and I need to create a reflection program to demonstrate the above. My question is, how do I use the .class file to be able to access it in my program and start using reflection? I'm using NetBeans.