GUI Commission Calculator Java applicaiton, programming assignment help

I need help.  I am learning to program this but, I am not sure how to and I would like someone else to code it.

Write a Java™ GUI application using NetBeans™ Integrated Development Environment (IDE) that calculates the total annual compensation of a salesperson.

Consider the following factors:

• The calculator should allow user to enter the amount of sales
• The calculator should allow user to select the level of commission rate from a list of pre-defined commission rate.  The three choices in the list are:

• • <Add a percentage here>
  • <Add a percentage here>
  • <Add a percentage here>

• The calculator should display the amount of commission in dollar, based on the amount of sales entered and the commission rate selected.
• The Java™ application should meet these technical requirements:
  • The application should have at least one class, in addition to the application's controlling class (a controlling class is where the main function resides).
  • There should be proper documentation in the source code.