Trying to run external script using Runtime.exec

Question

Hey,
I am trying to use Runtime.exec(cmd, evnp, dir) to execute a fortran program and get back its output, however it seems to always be hanging. Here is my code snippet :
            Process process = Runtime.getRuntime().exec(
                  "./fortranCodeName > inputFile.txt" , null, new File("/home/myRunDir/"));
            InputStream stream = new InputStream(process.getInputStream());
            InputStream error = new InputStreamr(process.getErrorStream());
            BufferedReader stdoutReader = new BufferedReader(new InputStreamReader(stream));
            BufferedReader erroutReader = new BufferedReader(new InputStreamReader(error));
            System.out.println(stream.available());  //returns 0
            System.out.println(error.available());     //returns 0
            while (true) {
                String line1 = stdoutReader.readLine();  //hangs here
                String line2 = erroutReader.readLine();
                if (line1 == null) {
                    break;
                System.out.println(line1);
                System.out.println(line2);
            }I know for a fact that this fortran code prints out stuff when run it in terminal, but I don't know if I have even set up my Runtime.exec statement properly. I think I am clearing out my error and input streams with the whole reader.readLine bit I have above, but I am not sure. If you replace the command with something like "echo helloWorld" or "pwd", it prints out everything properly. I also am fairly confident that I have no environmental variables that are used in the fortran code, as I received it from another computer and haven't set up any in my bash profile.
Any Ideas?

Answer 1

Okay, so I implemented the changes from that website (thanks by the way for that link, it helps me understand this a little better). However, my problem is still occuring. Here is my new code:
            class StreamThread extends Thread {
            InputStream is;
            String type;
            StreamThread(InputStream is, String type)
                this.is = is;
                this.type = type;
            public void run()
                try
                    InputStreamReader isr = new InputStreamReader(is); //never gets called
                    BufferedReader br = new BufferedReader(isr);
                    String line=null;
                    while ( (line = br.readLine()) != null)
                        System.out.println(type  +">"+  line);
                    } catch (IOException ioe)
                        ioe.printStackTrace();
        try {
            Process process = Runtime.getRuntime().exec(
                  "./fortranCodeName" , null, new File("/home/myRunDir/"));
            StreamThread stream = new StreamThread(process.getInputStream(), "OUTPUT");
            StreamThread errorStream = new StreamThread(process.getInputStream(), "ERROR");
            stream.start();
            errorStream.start();
            int exitVal = process.waitFor(); //hangs here
            System.out.println("ExitValue: " + exitVal);