I'm working with Java and I've been asked to Hotreload a jar file to an ejb-server.
So my question is (and yes I've googled it!), what is the definition of Hot reload anyway?
It is hot deployment and not hot reload of ejb, which means, updating an EJB without having to stop and restart the application server. Few application servers support this few don't. You don't have to worry about it, its application server that provides it for your use.
Few application servers does it seamlessly, for example, In weblogic, you can just copy a modified jar file into your applications directory, and changes will take place immediately.