Android：我怎麼捕獲這個異常

我一個重新使用代碼，在一個列表視圖分析並顯示RSS當從後面代理或沒有互聯網我獲得以下崩潰報告運行代碼的教程：

12-12 09:48:57.372: W/RssApp(1494): Exception while retrieving the input stream 
12-12 09:48:57.372: W/RssApp(1494): java.net.ConnectException: failed to connect to gigglepics.co.uk/188.121.41.139 (port 80): connect failed: ETIMEDOUT (Connection timed out) 
12-12 09:48:57.372: W/RssApp(1494):  at libcore.io.IoBridge.connect(IoBridge.java:114) 
12-12 09:48:57.372: W/RssApp(1494):  at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:192) 
12-12 09:48:57.372: W/RssApp(1494):  at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:459) 
12-12 09:48:57.372: W/RssApp(1494):  at java.net.Socket.connect(Socket.java:842) 
12-12 09:48:57.372: W/RssApp(1494):  at libcore.net.http.HttpConnection.<init>(HttpConnection.java:76) 
12-12 09:48:57.372: W/RssApp(1494):  at libcore.net.http.HttpConnection.<init>(HttpConnection.java:50) 
12-12 09:48:57.372: W/RssApp(1494):  at libcore.net.http.HttpConnection$Address.connect(HttpConnection.java:340) 
12-12 09:48:57.372: W/RssApp(1494):  at libcore.net.http.HttpConnectionPool.get(HttpConnectionPool.java:87) 
12-12 09:48:57.372: W/RssApp(1494):  at libcore.net.http.HttpConnection.connect(HttpConnection.java:128) 
12-12 09:48:57.372: W/RssApp(1494):  at libcore.net.http.HttpEngine.openSocketConnection(HttpEngine.java:316) 
12-12 09:48:57.372: W/RssApp(1494):  at libcore.net.http.HttpEngine.connect(HttpEngine.java:311) 
12-12 09:48:57.372: W/RssApp(1494):  at libcore.net.http.HttpEngine.sendSocketRequest(HttpEngine.java:290) 
12-12 09:48:57.372: W/RssApp(1494):  at libcore.net.http.HttpEngine.sendRequest(HttpEngine.java:240) 
12-12 09:48:57.372: W/RssApp(1494):  at libcore.net.http.HttpURLConnectionImpl.getResponse(HttpURLConnectionImpl.java:282) 
12-12 09:48:57.372: W/RssApp(1494):  at libcore.net.http.HttpURLConnectionImpl.getInputStream(HttpURLConnectionImpl.java:177) 
12-12 09:48:57.372: W/RssApp(1494):  at eu.MasterZangetsu.RssService.getInputStream(RssService.java:48) 
12-12 09:48:57.372: W/RssApp(1494):  at eu.MasterZangetsu.RssService.onHandleIntent(RssService.java:33) 
12-12 09:48:57.372: W/RssApp(1494):  at android.app.IntentService$ServiceHandler.handleMessage(IntentService.java:65) 
12-12 09:48:57.372: W/RssApp(1494):  at android.os.Handler.dispatchMessage(Handler.java:99) 
12-12 09:48:57.372: W/RssApp(1494):  at android.os.Looper.loop(Looper.java:137) 
12-12 09:48:57.372: W/RssApp(1494):  at android.os.HandlerThread.run(HandlerThread.java:60) 
12-12 09:48:57.372: W/RssApp(1494): Caused by: libcore.io.ErrnoException: connect failed: ETIMEDOUT (Connection timed out) 
12-12 09:48:57.372: W/RssApp(1494):  at libcore.io.Posix.connect(Native Method) 
12-12 09:48:57.372: W/RssApp(1494):  at libcore.io.BlockGuardOs.connect(BlockGuardOs.java:85) 
12-12 09:48:57.372: W/RssApp(1494):  at libcore.io.IoBridge.connectErrno(IoBridge.java:127) 
12-12 09:48:57.372: W/RssApp(1494):  at libcore.io.IoBridge.connect(IoBridge.java:112) 
12-12 09:48:57.372: W/RssApp(1494):  ... 20 more 
12-12 09:48:57.382: W/dalvikvm(1494): threadid=11: thread exiting with uncaught exception (group=0x40a71930) 
12-12 09:48:57.402: E/AndroidRuntime(1494): FATAL EXCEPTION: IntentService[RssService] 
12-12 09:48:57.402: E/AndroidRuntime(1494): java.lang.NullPointerException 
12-12 09:48:57.402: E/AndroidRuntime(1494):  at eu.MasterZangetsu.PcWorldRssParser.parse(PcWorldRssParser.java:33) 
12-12 09:48:57.402: E/AndroidRuntime(1494):  at eu.MasterZangetsu.RssService.onHandleIntent(RssService.java:33) 
12-12 09:48:57.402: E/AndroidRuntime(1494):  at android.app.IntentService$ServiceHandler.handleMessage(IntentService.java:65) 
12-12 09:48:57.402: E/AndroidRuntime(1494):  at android.os.Handler.dispatchMessage(Handler.java:99) 
12-12 09:48:57.402: E/AndroidRuntime(1494):  at android.os.Looper.loop(Looper.java:137) 
12-12 09:48:57.402: E/AndroidRuntime(1494):  at android.os.HandlerThread.run(HandlerThread.java:60)

這發生在inputStream.close（）;

public List<RssItem> parse(InputStream inputStream) 
     throws XmlPullParserException, IOException { 
    try { 
     XmlPullParser parser = Xml.newPullParser(); 
     parser.setFeature(XmlPullParser.FEATURE_PROCESS_NAMESPACES, false); 
     parser.setInput(inputStream, null); 
     parser.nextTag(); 
     return readFeed(parser); 
    } finally { 
     inputStream.close(); 

    } 
}

所有我想要做的就是抓住這個例外，以確保應用程序不會崩潰，而是顯示錯誤消息

一切，我嘗試似乎仍然崩潰，並給出了完全不同的錯誤。我必須失去了真正的基本的東西

來源

2013-12-12 Master Zangetsu

在finally塊中添加try/catch塊沒有什麼可恥:)。檢查[這]（http://stackoverflow.com/questions/6095664/putting-try-catch-finally-block-inside-another-finally-block） –

正如下面的Kevin Bowersox評論所述，你的問題不在inputStream 。關（）; –

我補充說他建議不起作用。其他建議？ –

代碼缺少實際catch語句：

try { 
    XmlPullParser parser = Xml.newPullParser(); 
    parser.setFeature(XmlPullParser.FEATURE_PROCESS_NAMESPACES, false); 
    parser.setInput(inputStream, null); 
    parser.nextTag(); 
    return readFeed(parser); 
}catch(IllegalArgumentException e){ //Replace this with the more specific exception 
    //do something 
}catch(Excpetion e){ //You can have multiple catch blocks from specific to general 
    //do something 
}finally { 
    inputStream.close(); 

}

一旦你添加此代碼仍然收到一個錯誤，因爲inputStream爲空，並在finally塊拋出一個NullPointerException 。有兩種方法可以處理這個問題。

首先是簡單地抓住NullPointerException在finally塊：

try { 
    XmlPullParser parser = Xml.newPullParser(); 
    parser.setFeature(XmlPullParser.FEATURE_PROCESS_NAMESPACES, false); 
    parser.setInput(inputStream, null); 
    parser.nextTag(); 
    return readFeed(parser); 
}catch(IllegalArgumentException e){ //Replace this with the more specific exception 
    //do something 
}catch(Excpetion e){ //You can have multiple catch blocks from specific to general 
    //do something 
}finally { 
    try{ 
     inputStream.close(); 
    }catch(Exception e){ 
     //do something 
    } 
}

第二不通過不附加保護條件接受在方法的開始的零InputStream。

public List<RssItem> parse(InputStream inputStream) 
    throws IllegalArgumentException { 

    if(inputStream == null){ 
     throw new IllegalArgumentException(); 
    } 
}

可稱爲像：

try{ 
     someObject.parse(null); 
    }catch(IllegalArgumentException e){ 
     //do something 
    }

來源

2013-12-12 09:39:15

此方法拋出XmlPullParserException，IOException。沒有必要趕上Excpetion。 – Prabhakaran

@Prabhakaran我只是用它來演示捕捉多個異常。 –

這很酷.. @Kevin Bowersox – Prabhakaran

做這樣

try { 

}catch(IllegalArgumentException e){ //Added this catch block. 

} 
finally { 
    inputStream.close(); 
}

來源

2013-12-12 09:39:26 Prabhakaran

爲什麼downvote？謹慎解釋.. – Prabhakaran

我沒有投票，但他的例外來自finally塊 –

如何從此行獲得IllegalArgumentException inputStream.close（）; – Prabhakaran

只要把catch塊，然後catch特別exception。

try{ 
    // your implementation 
}catch(Exception e){ 
    // handle the exception 
}finally{ 
try{ 
    // do what ever the thing should diffidently happens 
    }catch(Exception e){ 

    } 
}

來源

2013-12-12 09:39:27

爲什麼downvote？ – Jhanvi

ohh來吧。這裏有一個人頭腦問題。在此解答每個答案。 –

Android：我怎麼捕獲這個異常

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