Search code examples
javastreamprocessbuilder

How to redirect ProcessBuilder's output to a string?


I am using the following code to start a process builder. I want to know how can I redirect its output to a String.

ProcessBuilder pb = new ProcessBuilder(
    System.getProperty("user.dir") + "/src/generate_list.sh", filename);
Process p = pb.start();

I tried using ByteArrayOutputStream but it didn't seem to work.


Solution

  • Read from the InputStream. You can append the output to a StringBuilder:

    BufferedReader reader = 
                    new BufferedReader(new InputStreamReader(process.getInputStream()));
    StringBuilder builder = new StringBuilder();
    String line = null;
    while ( (line = reader.readLine()) != null) {
       builder.append(line);
       builder.append(System.getProperty("line.separator"));
    }
    String result = builder.toString();