Question

I’m trying to run the following command using Java runtime:

find /home/Alison/workspace/FunctionalTestFramework/src/com/q1labs/qa/selenium/screens -type d |   awk -F/ 'NF <= old_NF {print prev} {old_NF=NF; prev=$0} END {print $0}'

The command works fine when entered directly into a Terminal but when ran in the following function it gives the following error:

find: paths must precede expression: |
Usage: find [-H] [-L] [-P] [-Olevel] [-D help|tree|search|stat|rates|opt|exec] [path...] [expression]
Process exitValue: 1

The Java function:

     try
        {            
            Runtime rt = Runtime.getRuntime();
            Process proc = rt.exec("find /home/Alison/workspace/FunctionalTestFramework/src/com/q1labs/qa/selenium/screens -type d |   awk -F/ 'NF <= old_NF {print prev} {old_NF=NF; prev=$0} END {print $0}'");
            InputStream stderr = proc.getErrorStream();
            InputStreamReader isr = new InputStreamReader(stderr);
            BufferedReader br = new BufferedReader(isr);
            String line = null;
            while ( (line = br.readLine()) != null)
                System.out.println(line);
            int exitVal = proc.waitFor();
            System.out.println("Process exitValue: " + exitVal);
        } catch (Throwable t)
          {
            t.printStackTrace();
          }

Answer 1

As I commented, you could exec a shell, e.g. /bin/sh with -c followed by the string to interpret. This is what the system(3) function in standard C does on Unix & Posix systems.

However, I would just suggest to write a shell script doing what your complex command does, and exec that shell script. This gives the ability to (test and to) improve that shell script without changing your Java code.