java.net.ConnectException: localhost/127.0.0.1:8080

Android访问自己的Tomcat出现java.net.ConnectException: localhost/127.0.0.1:8080 NetworkSecurityConfig: No Network Security Config specified, using platform default

在浏览器可以访问都是可以成功，为什么真机和模拟器出现错误！权限什么的都有，为什么一直失败！

1、如果在真机上时，可以用pc的真实ip代替127.0.0.1和localhost

2、如果在模拟器上，可以用10.0.2.2代替127.0.0.1和localhost

模拟器默认把127.0.0.1和localhost当做本身了，在模拟器上可以用10.0.2.2代替127.0.0.1和localhost

new Thread(new Runnable() {
            @Override
            public void run() {
                URL url;
                try {
                    //真机使用电脑真实ip做为host 我的电脑ip为192.168.1.111
                    url = new URL("http://192.168.1.111:8080/student/getAllStudent");
                    //模拟器使用 10.0.2.2 作为host
                    url = new URL("http://10.0.2.2:8080/student/getAllStudent");
                    HttpURLConnection connection= (HttpURLConnection) url.openConnection();
                    connection.setRequestMethod("GET");
                    connection.connect();
                    if (connection.getResponseCode()==200){
                        InputStream inputStream = connection.getInputStream();
                        BufferedReader bufferedReader=
                                new BufferedReader(
                                        new InputStreamReader(inputStream,"utf-8"));
                        String line;
                        final StringBuilder sb=new StringBuilder();
                        while ((line=bufferedReader.readLine())!=null){
                            sb.append(line);
                        }
                        Log.e(TAG, "run: 请求结果："+sb.toString() );
                        runOnUiThread(new Runnable() {
                            @Override
                            public void run() {
                                textView.setText(sb.toString());
                            }
                        });
                    }else {
                        Log.e(TAG, "run: 请求失败！" );
                    }

                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        }).start();