How to simulate firwalls and proxies when developing code?

Question

I write code that often needs to work in a limited environment. I sometimes code the house where it works well, and as soon as I put it to the test, McAfee or another firewall blocks it. Sometimes it’s not possible to disable this protection.

I need a test suite for my home development environment where I can simulate all these limitations without setting them myself (for example, it is my experience that it is very difficult / impossible to clear all traces of mcafee after you installed it). I also need to simulate proxies.

I am writing Java code if this helps.

[EDIT: so some Java libraries will be great for this]

Answer 1

You can use VMware (or VirtualBox) with various test settings.

Answer 2

Try node.js . Also consider an example proxy implementation