public class MainActivity extends AppCompatActivity {

    private static final String TAG = MainActivity.class.getName();

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }
        public void loadJson(View view) {
          new Thread(new Runnable() {
              @Override
              public void run() {
                  try {
                      URL url=new URL("http://10.0.2.2:9102/get/text");
                      HttpURLConnection Connection = (HttpURLConnection) url.openConnection();
                      Connection.setConnectTimeout(10000);
                      Connection.setRequestMethod("GET");
                      Connection.setRequestProperty("Accept-Language","zh-CN,zh;q=0.9");
                      Connection.setRequestProperty("Accept-Encoding","gzip, deflate");
                      Connection.setRequestProperty("Accept","*/*");
                      Connection.connect();
                      //结果码
                      int responseCode = Connection.getResponseCode();
                      if (responseCode==200) {
                          Map<String, List<String>> headerFields = Connection.getHeaderFields();
                          Set<Map.Entry<String, List<String>>> entries = headerFields.entrySet();
                          for (Map.Entry<String, List<String>> entry : entries) {
                              Log.d(TAG, entry.getKey()+"---------->"+entry.getValue());
                          }
                          Object content = Connection.getContent();
                          Log.d(TAG, "content--->"+content);
                      }
                  } catch (Exception e) {
                      e.printStackTrace();
                  }
              }
          }).start();
        }
}

以下是异常，PS：我用的是Android studio的原生模拟器