我想獲得網絡時間，爲什麼這個方法的返回值總是爲0

Question

爲什麼當我使用getWebsiteLongtime（）獲取日期時，時間值總是0？

private static String webUrl = "https://www.baidu.com"; 

private static long getWebsiteLongtime(String webUrl) { 
     try { 
      URL url = new URL(webUrl); 
      HttpURLConnection uc = (HttpURLConnection) url.openConnection(); 
      uc.connect(); 
      long time = uc.getDate(); 
      return time; 
     } catch (MalformedURLException e) { 
      e.printStackTrace(); 
     } catch (IOException e) { 
      e.printStackTrace(); 
     } 
     return new Date().getTime(); 
    } 

Answer 1

一個問題：你有AndroidManifest的「互聯網」權限嗎？

<uses-permission android:name="android.permission.INTERNET"/>

在另一方面，我試圖做一個快速測試這個和它的工作：

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

    new AsyncTask<String, Void, String>(){ 

     private String time = ""; 

     @Override 
     protected String doInBackground(String... strings) { 
      return String.valueOf(getWebsiteLongtime(webUrl)); 
     } 

     @Override 
     protected void onPostExecute(String t) { 
      time = t; 
      Log.i(TAG, "TIME: " + time); 
     } 
    }.execute(); 

} 

private static long getWebsiteLongtime(String webUrl) { 
    try { 
     URL url = new URL(webUrl); 
     HttpURLConnection uc = (HttpURLConnection) url.openConnection(); 
     uc.connect(); 
     long time = uc.getDate(); 
     Log.d(TAG, "Time 1: " + time); 
     return time; 
    } catch (IOException e) { 
     Log.e(TAG, "Exception!", e); 
    } 
    Log.d(TAG, "Time 2: " + new Date().getTime()); 
    return new Date().getTime(); 
} 

日誌是：

11-23 10:13 ：06.366 31893-31935/com.archison.tests.myapplication D/MainActivity：Time 1：1479892387000

11-23 10：13：06.367 31893-31893/com.archison.tests.myapplication I/MainActivity：TI ME：1479892387000

希望我幫助:)