code: private static String runCommand(final String[] cmd)
              throws IOException, InterruptedException {
          ByteArrayOutputStream baos = new ByteArrayOutputStream();
          Process process = Runtime.getRuntime().exec(cmd);
          int c;
          InputStream in = process.getInputStream();
          while ((c = in.read()) != -1) {
              baos.write(c);
          }
          in = process.getErrorStream();
          while ((c = in.read()) != -1) {
              baos.write(c);
          }
          process.waitFor();
          return new String(baos.toByteArray());
      }
docs: Run the command synchronously and return clubbed standard error and
  output stream's data.