Should I use Scala or Java or Node.js?

I read quite extensively about Scala programming language.So far, I understand the following concepts about Scala :

• Runs on conventional JVM
• Inter-operable with Java
• Combination of OOP and functional programming concepts
• Statically typed and extensible
• Less code and do more paradigm

My requirement is quite simple. I have to code a business module which follows a set of predefined rules that should be loaded dynamically during runtime. For example, Company A has a set of business rules and company B has another set. When a different program accesses the business module API , it should load the rules of that particular company and respond to the service. The business module will involve DB access and few more web service calls internally and extensive xml parsing.

We need this module to be as much scalable as possible. I can use AOP concepts of JAVA , but it is only too complex. The code will not be maintainable in the future.

Is Scala a better option in this case ? I am even considering Node.js

Please let me know you thoughts!