communication - Java external program

Question

I'd like to start external third party application from my Java application. This external application should run all the time whilst my java application runs.

From time to time (it depends on user interaction) my java app should be able to read and write to this external application via stdin and stdout.

How can I do that?

Answer 1

Essentially, you will need multiple threads in Java that watch for the outside process to end and which shuffle around its input/output/error streams so that your main Java app has access to it.

There are more "basic" ways to do it with classes like Process, but I would suggest Apache Commons-exec, which provides some useful tools for handling return values and I/O.