I have three Java applications that will connect to the same Ignite node (running on a particular VM) to access the same cache store.
Is there a step-by-step procedure on how to run a node outside Java application (from command prompt, may be) and connect my Java apps to it?
Your Java applications should serve as client nodes in your cluster. More information about client/sever mode can be found in the documentation. Server node(s) could be started from command line, it's described here. Information about running with a custom configuration could be found there as well. You need to set up discovery in order to make the entire thing work. It should be done on every node (incl. client nodes). I'd recommend you to use static IP finder in the configuration.