IVR - Tells you your cellphone credit

I was tasked with developing an application 开发者_如何转开发that would be able to tell someone their cellphone credit balance via some IVR system. I dont know where to begin. Does anyone have a knowledge of GSM who could be able to give me some directions for this project.

You should look into Asterisk AGI scripts. They allow you to do more than Asterisk API. I currently have lots of AGI scripts in Perl but it says that Java is also supported. Maybe this link will help you. Basically you will create some extended Java app which will return you current Balance. Asterisk IVR would read this value from AGI and then play it.

Asterisk may be a good solution for your problem. Asterisk provide the API Asterisk Gateway Interface(AGI), that allows you to control the call flow using an external programming language, including Java.

Some of the libraries/frameworks that implement AGI in Java are: astivetoolkit.org and asterisk-java.org.

Good luck.