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javalinuxprocess

Collect Linux command output

I am now on a linux machine. I have a Java program which would run some linux command, for example ps, top, list or free -m.

The way to run a command in Java is as follows:

Process p = Runtime.getRuntime().exec("free -m");

How could I collect the output by Java program? I need to process the data in the output.

Solution

  • Use Process.getInputStream() to get an InputStream that represents the stdout of the newly created process.

    Note that starting/running external processes from Java can be very tricky and has quite a few pitfalls.

    They are described in this excellent article, which also describes ways around them.