static Process forkProcess(File directory,String... processArgs) throws IOException {
  ProcessBuilder processBuilder=new ProcessBuilder(processArgs);
  processBuilder.directory(directory);
  processBuilder.redirectErrorStream(true);
  return processBuilder.start();
}

static Process forkProcess ( File directory , String ... processArgs ) throws IOException { ProcessBuilder processBuilder = new ProcessBuilder ( processArgs ) ; processBuilder . directory ( directory ) ; processBuilder . redirectErrorStream ( true ) ; return processBuilder . start ( ) ; }
create operating system process and redirect all process output stream to supplied file .
