ruby on rails to command line interaction

Very new to Ruby so please try to look past my ignorance. Cause I have no idea what I am talking about currently. However I know the ability to do what I want exists. Essentially I have some开发者_如何学JAVA JAVA server side that can be used via a command line. I am trying to figure out where and how to begin with communicating in the same notion of me typing it out in the cli without actually typing it out to the cli. Basicly I want to pass the commands like as if I was using the CLI but Im not. Does that make sense?

Its for a CLI to UI conversion. I have seen the process done RoR to JAVA in such a fashion but where to begin I couldn't tell ya to save my life.

First of all, I would suggest at least looking into jRuby, which can interact with java classes as though they were ruby classes.

If you still want the cli integration, the naive approach is extremely simple, all you need to do is wrap your cli command in backticks (`) and it will execute the command as if you typed it into a shell, and return the results as a string.

If you need to do this very frequently, check out https://github.com/rtomayko/posix-spawn which is a much more efficient way of doing it then the backtick approach.

If the Java program has a command prompt of its own, look into popen. It allows you to open a subprocess as an I/O stream allowing you to send it input and read its output. If all you need is to start the process and get its output then use backticks as suggested by Matt Briggs:

output = `the-command-to-start-the-java-program`