I want to build a 3-tiers system for EHS(Electronic Health Record) or EMS(Electronic Medical Record), but since i don't have much time '10 days' i want to take the simplest fastest complete route, so wich platform to use?
I'll try to answer you as in a real project, because I think you need an answer, let's forget about the time restriction and let's try to help:
First try to check this about meaning of layer or tier
What's the difference between "Layers" and "Tiers"?
These configurations are available in Java to organize your 3 tiers, I will talk only about the standard ecosystem:
There will be a single tier for each of these configurations, note however that to have more than 2 tiers you need an application server in the middle to manage the business logic. That let you with less choices that at least use an app server. All of them using EJB, which is part of the Java EE specification.
Maybe you get confused also about thinking that web programming is a must in your application. You have to know that you can connect your Swing client to EJB. That way you can use your skills in JSE (I guess Swing) but using a small subset of the Java EE specification (EJB).
There is also a final consideration, you can have several layers in each of the shown tiers, For instance, you can have in your EJB layer a facade tier and a services tier. You can check the logical ways to organize it in this great book Real World Java EE Patterns Rethinking Best Practices:
regards