该HTML帖子应该出现的响应在哪里？

Question

所以即时练习此代码from here，我想知道结果返回到哪里？

例如，我故意更改网址使其无效，并且我没有看到与的回应没有工作！任何地方。我看着console，logcat，并没有如后的任何指标的迹象是成功还是失败。

我怎么找到这个？谢谢！

public class MainActivity extends Activity implements OnClickListener { 

TextView tvIsConnected; 
EditText etName,etCountry,etTwitter; 
Button btnPost; 

Person person; 
@Override 
protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_main); 

    // get reference to the views 
    tvIsConnected = (TextView) findViewById(R.id.tvIsConnected); 
    etName = (EditText) findViewById(R.id.etName); 
    etCountry = (EditText) findViewById(R.id.etCountry); 
    etTwitter = (EditText) findViewById(R.id.etTwitter); 
    btnPost = (Button) findViewById(R.id.btnPost); 

    // check if you are connected or not 
    if(isConnected()){ 
     tvIsConnected.setBackgroundColor(0xFF00CC00); 
     tvIsConnected.setText("You are conncted"); 
    } 
    else{ 
     tvIsConnected.setText("You are NOT conncted"); 
    } 

    // add click listener to Button "POST" 
    btnPost.setOnClickListener(this); 

} 

public static String POST(String url, Person person){ 
    InputStream inputStream = null; 
    String result = ""; 
    try { 

     // 1. create HttpClient 
     HttpClient httpclient = new DefaultHttpClient(); 

     // 2. make POST request to the given URL 
     HttpPost httpPost = new HttpPost(url); 

     String json = ""; 

     // 3. build jsonObject 
     JSONObject jsonObject = new JSONObject(); 
     jsonObject.accumulate("name", person.getName()); 
     jsonObject.accumulate("country", person.getCountry()); 
     jsonObject.accumulate("twitter", person.getTwitter()); 

     // 4. convert JSONObject to JSON to String 
     json = jsonObject.toString(); 

     // ** Alternative way to convert Person object to JSON string usin Jackson Lib 
     // ObjectMapper mapper = new ObjectMapper(); 
     // json = mapper.writeValueAsString(person); 

     // 5. set json to StringEntity 
     StringEntity se = new StringEntity(json); 

     // 6. set httpPost Entity 
     httpPost.setEntity(se); 

     // 7. Set some headers to inform server about the type of the content 
     httpPost.setHeader("Accept", "application/json"); 
     httpPost.setHeader("Content-type", "application/json"); 

     // 8. Execute POST request to the given URL 
     HttpResponse httpResponse = httpclient.execute(httpPost); 

     // 9. receive response as inputStream 
     inputStream = httpResponse.getEntity().getContent(); 

     // 10. convert inputstream to string 
     if(inputStream != null) 
      result = convertInputStreamToString(inputStream); 
     else 
      result = "Did not work!"; 

    } catch (Exception e) { 
     Log.d("InputStream", e.getLocalizedMessage()); 
    } 

    // 11. return result 
    return result; 
} 

public boolean isConnected(){ 
    ConnectivityManager connMgr = (ConnectivityManager) getSystemService(Activity.CONNECTIVITY_SERVICE); 
     NetworkInfo networkInfo = connMgr.getActiveNetworkInfo(); 
     if (networkInfo != null && networkInfo.isConnected()) 
      return true; 
     else 
      return false;  
} 
@Override 
public void onClick(View view) { 

    switch(view.getId()){ 
     case R.id.btnPost: 
      if(!validate()) 
       Toast.makeText(getBaseContext(), "Enter some data!", Toast.LENGTH_LONG).show(); 
      // call AsynTask to perform network operation on separate thread 
      new HttpAsyncTask().execute("http://hmkcode.appspot.com/jsonservlet"); 
     break; 
    } 

} 
private class HttpAsyncTask extends AsyncTask<String, Void, String> { 
    @Override 
    protected String doInBackground(String... urls) { 

     person = new Person(); 
     person.setName(etName.getText().toString()); 
     person.setCountry(etCountry.getText().toString()); 
     person.setTwitter(etTwitter.getText().toString()); 

     return POST(urls[0],person); 
    } 
    // onPostExecute displays the results of the AsyncTask. 
    @Override 
    protected void onPostExecute(String result) { 
     Toast.makeText(getBaseContext(), "Data Sent!", Toast.LENGTH_LONG).show(); 
    } 
} 

private boolean validate(){ 
    if(etName.getText().toString().trim().equals("")) 
     return false; 
    else if(etCountry.getText().toString().trim().equals("")) 
     return false; 
    else if(etTwitter.getText().toString().trim().equals("")) 
     return false; 
    else 
     return true;  
} 
private static String convertInputStreamToString(InputStream inputStream) throws IOException{ 
    BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(inputStream)); 
    String line = ""; 
    String result = ""; 
    while((line = bufferedReader.readLine()) != null) 
     result += line; 

    inputStream.close(); 
    return result; 

} 
} 

Answer 1

在POST的catch块（）添加一行

result="Exception: " + e.getMessage(); 

然后在onPostExecute

Toast (....,result,...);