不能将另一个java.lang.Object []强制转换为java.lang.String []带有简单后台任务<Void>的问题

Question

我知道这与传递参数有关，但就我而言，一切都是虚空的，那又如何呢？编译时没有错误！

public class MainActivity extends AppCompatActivity {
  private PApplet sketch;

  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    FrameLayout frame = new FrameLayout(this);
    frame.setId(CompatUtils.getUniqueViewId());
    setContentView(frame, new ViewGroup.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT,
                                                     ViewGroup.LayoutParams.MATCH_PARENT));

    sketch = new MiniEFIS();

    PFragment fragment = new PFragment(sketch);
    fragment.setView(frame, this);

    listen client = new listen();
    client.receive();
  }

和

public class listen {

   public AsyncTask async_client;

    @SuppressLint("StaticFieldLeak")
    public void receive() {

         async_client = new AsyncTask<Void, Void, Void>() {

            protected Void doInBackground(Void... params) {
                boolean run = true;
                try {
                    ... some OK code here
                    }
                } catch (IOException e) {
                    Log.e("UDP client IOException", "error: ", e);
                    run = false;

                }
                return null;
            }
        };

请帮助提供正确的声明。