问通过openSSH在远程计算机上的Powershell命令

EN

public class Example {
  public static class Writers exte ds Thread {
    Process process;
    Writers(Process p) {
      process =p;
    }
 
  public void run() {
    try {
      OutputStreamWriter writer= new OutputStreamWriter(process.getOutputStream);
      String command = "expect -c 'spawn ssh user@host ; expect \"password\" ; send \"passcode\\r\"; interact' \n";
      writer.write(command);
      writer.write("echo \"hello123\");
      writer.flush();
    } catch (Exception e) {}
    }
    
    public static void main(String[] args) throws Exception {
        ProcessBuilder builder = new ProcessBuilder("bash");
        builder.redirectErrorStream(true);
        Process process = builder.start();
        Example.Writers writers = new Example.Writers(process);
        writers.start();

        BufferedReader stdout = new BufferedReader( new InputStreamReader(process.getInputStream()));
        String s = null;
        while((s= stdout.readLine()) != null) {
           System.out.println(s);
        }
    }
}

OUTPUT:
I see only Windows powershell startup logo and nothing after that.

Tell me why this hello123 not getting printed.
Or, why the powershell output stream not getting redirected to output stream of linux machine ?

manually opening interactive ssh shell and running powershell commands run perfectly, but not via code.