Question

我在崩溃日志中看到这个错误每周数百次，但我已经花了几个星期的时间试图追赶错误而没有任何成功。我无法在任何设备上重现它。这是堆栈跟踪：

Posix.java:-2 in "libcore.io.Posix.recvfromBytes"
Posix.java:131 in "libcore.io.Posix.recvfrom"
BlockGuardOs.java:164 in "libcore.io.BlockGuardOs.recvfrom"
IoBridge.java:513 in "libcore.io.IoBridge.recvfrom"
PlainSocketImpl.java:489 in "java.net.PlainSocketImpl.read"
PlainSocketImpl.java:46 in "java.net.PlainSocketImpl.access$000"
PlainSocketImpl.java:241 in "java.net.PlainSocketImpl$PlainSocketInputStream.read"
AbstractSessionInputBuffer.java:103 in "org.apache.http.impl.io.AbstractSessionInputBuffer.fillBuffer"
AbstractSessionInputBuffer.java:191 in "org.apache.http.impl.io.AbstractSessionInputBuffer.readLine"
DefaultResponseParser.java:82 in "org.apache.http.impl.conn.DefaultResponseParser.parseHead"
AbstractMessageParser.java:174 in "org.apache.http.impl.io.AbstractMessageParser.parse"
AbstractHttpClientConnection.java:180 in "org.apache.http.impl.AbstractHttpClientConnection.receiveResponseHeader"
DefaultClientConnection.java:235 in "org.apache.http.impl.conn.DefaultClientConnection.receiveResponseHeader"
AbstractClientConnAdapter.java:259 in "org.apache.http.impl.conn.AbstractClientConnAdapter.receiveResponseHeader"
HttpRequestExecutor.java:279 in "org.apache.http.protocol.HttpRequestExecutor.doReceiveResponse"
HttpRequestExecutor.java:121 in "org.apache.http.protocol.HttpRequestExecutor.execute"
DefaultRequestDirector.java:428 in "org.apache.http.impl.client.DefaultRequestDirector.execute"
AbstractHttpClient.java:555 in "org.apache.http.impl.client.AbstractHttpClient.execute"
AbstractHttpClient.java:487 in "org.apache.http.impl.client.AbstractHttpClient.execute"
AbstractHttpClient.java:465 in "org.apache.http.impl.client.AbstractHttpClient.execute"
Utilities.java:484 in "com.myapp.android.Utilities$8.run"

以下是错误来自的代码块...发生崩溃的确切位置是HttpResponse response = httpclient.execute(httppost);：

 public static HttpPost postData(String URL, final List<NameValuePair> params, final Handler handler) {
        // Create a new HttpClient and Post Header
        //android.util.Log.d("Utilities", "Called postData");
        final HttpClient httpclient = new DefaultHttpClient();
        //httpclient.
        final HttpPost httppost = new HttpPost(URL);
        final Message msg = new Message();
        final Bundle dataBundle = new Bundle();
        final ByteArrayOutputStream out = new ByteArrayOutputStream();

        new Thread(){
            @Override
            public void run(){
                String error = "";
                String data = "";
                try {
                    httppost.setEntity(new UrlEncodedFormEntity(params));
                    HttpResponse response = httpclient.execute(httppost);
                    StatusLine statusLine = response.getStatusLine();
                    if(statusLine.getStatusCode() == HttpStatus.SC_OK){
                        response.getEntity().writeTo(out);
                        out.close();
                        data = out.toString();
                    } else{
                        error = EntityUtils.toString(response.getEntity());
                    }
                } catch (ClientProtocolException e) {
                    AirbrakeNotifier.notify(e);
                    error = e.toString();
                } catch (IOException e) {
                    AirbrakeNotifier.notify(e);
                    error = e.toString();
                } catch (Exception ex) {
                    AirbrakeNotifier.notify(ex);
                    error = ex.toString();
                }
                dataBundle.putString("error", error);
                dataBundle.putString("data", data);
                msg.setData(dataBundle);
                handler.dispatchMessage(msg);
            }
        }.start();
        return httppost;
    }

非常感谢任何有关最终解决这个问题的帮助！

Answer 1

在我看来，这个问题的罪魁祸首不是你的应用程序，而是远程端（即HTTP服务器）。最可能的事情是HTTP服务器突然重置连接，这会导致应用程序中出现SocketException。在生产环境中，这些事情经常发生。它可能是由HTTP服务器的过载引起的，一些特殊情况可能导致服务器关闭（HTTP请求泛滥，甚至在远程服务器资源耗尽时增加的请求数量;服务器也可能耗尽它的本地套接字池...原因可能是几十个。

如果这些错误的比例与成功的HTTP请求相比较低，我不会太担心，我只是将这段代码包装成try { ... } catch (SocketException e) { ... }语句并显示给用户一个对话框告诉他们请求失败，他们应该重试。

我当然会尝试确定这种行为的原因：我尝试匹配其中一个异常的时间，并尝试深入了解HTTP服务器日志，以便尝试确定这种突然断开的原因（假设您可以访问该日志和其他诊断工具）。正如我之前所说的那样，调试可能是一件愚蠢的事情或者更复杂，但我敢打赌这就是问题。

Answer 2

“java.net.SocketException：Socket closed”异常可能在各种情况下发生。服务器端关闭连接，如nKn建议，或客户端（您的应用程序）关闭连接。即使您不知道这样做，也可能会有一些不太明显的代码可能导致关闭套接字，如Thread.interrupt（）或ExecutorService.shutdownNow（）。

另一方面，如果它实际上发生在服务器端，我会建议你实施重试 - 通常做3次尝试并且通常就足够了。

Answer 3

您目前正在接受客户端lib配置的默认值。也许您想要更多地控制您的Httpclient lib，特别是关于套接字TIMEOUT设置。不要等待服务器做出意想不到的事情。设置比默认值更短的超时，并以对用户有意义的方式控制错误＆＃34;稍后再尝试msg＆＃34; ....

如果您正在使用默认的android httpclient，您可能需要查看与新的Apache客户端版本保持同步的替代方案......

https://hc.apache.org/httpcomponents-client-4.3.x/android-port.html

https://code.google.com/p/httpclientandroidlib/

general background async client

并注意，使用其中任何一个，您都可以考虑（在Wifi上）或（在4G上）您可以拨打detailed timeout profiles，您可以使用以下代码控制超时：

public void create(int method, final String url, final String data) {
    this.method = method;
    this.url = url;     
    this.data = data;
    if(method == GET){
        this.config = RequestConfig.custom()
            .setConnectTimeout(6 * 1000)
            .setConnectionRequestTimeout(30 * 1000)
            .setSocketTimeout(30 * 1000)                
            .build();
    } else{
        this.config = RequestConfig.custom()
                .setConnectTimeout(6 * 1000)
                .setConnectionRequestTimeout(30 * 1000)
                .setSocketTimeout(60 * 1000)                
                .build();           
    }
    this.context = HttpClientContext.create();

使用处理程序和UI回调，以便您可以显示所需的任何警告对话框

在runnable中您拥有＆＃39; .. client.exec（请求$ Type）＆＃39;

        if(httprc < HttpStatus.SC_METHOD_NOT_ALLOWED){

            Log.d(TAG, "entityTYP " +response.getEntity().getClass().getName());
            processEntity(response.getEntity());
            response.close();
        }else{
            Log.d(TAG, "ERR httprc " +httprc);
            throw new IOException("httprc " +httprc +" on " +method);
            }                               
        this.context.getConnection().close();
} catch (Exception e) {  // this will catch your 'socketException'
   // catch and use the looper to direct to the desired UI thread handle
    handler0.sendMessage(Message.obtain(handler,
            HttpConnection.DID_ERROR, e.getMessage()));
}

回到UI线程，你可以根据需要控制多个diff处理程序的警报....

           handler0 = new Handler() {
               public void handleMessage(Message message) {
                 switch (message.what) {
                 case HttpConnection.DID_START: {
                   break;
                 }
                 case HttpConnection.DID_SUCCEED: {                                          
                   break;
                 }
                 case HttpConnection.DID_ERROR: {
                       toggleSpin(false);
                       cleanup();
                    //have access to orig message.obj here as well
                       Toast.makeText(Speech_API_Activity.this, getResources().getString(R.string.heroku_msg_mux),
                            Toast.LENGTH_SHORT).show();
                       break;
                     }

如有必要，您可以按域建立差异超时配置文件。学习所有构建器的东西并用其他2个httpclient包配置东西需要时间，但是，它可能值得花时间，因为你可以设置它做任何你想做的事情，你完全控制异常和你想要的东西路由回UI。

Answer 4

您正在使用方法返回的HttpPost对象做什么发布数据（...）？这可能是需要考虑的原因之一。请注意那里是两个线程，一个主线程和另一个产生的线程上方。
在finally块中，您需要关闭httpClient和
之类的资源响应以及完全清空响应输入流。参见示例以供参考。
在UrlEncodedFormEntity上明确设置charset，可能是UTF-8

Answer 5

尝试使用此

public static String WebserviceResponseHandle(String url,
        List<NameValuePair> namvaluePair) {
    String result = null;
    try {
        HttpParams httpParams = new BasicHttpParams();
        HttpConnectionParams.setConnectionTimeout(httpParams, 10000);
        HttpConnectionParams.setSoTimeout(httpParams, 10000);
        HttpClient client = new DefaultHttpClient(httpParams);
        HttpPost httppost = new HttpPost(url);
        httppost.setEntity(new UrlEncodedFormEntity(namvaluePair));
        HttpResponse response = client.execute(httppost);
        HttpEntity entity = response.getEntity();

        // If the response does not enclose an entity, there is no need
        if (entity != null) {
            InputStream instream = entity.getContent();
            result = convertStreamToString(instream);

        }
    } catch (Exception e) {
        e.printStackTrace();
    }
    return result;
}


    private static String convertStreamToString(InputStream is) {
    /*
     * To convert the InputStream to String we use the
     * BufferedReader.readLine() method. We iterate until the BufferedReader
     * return null which means there's no more data to read. Each line will
     * appended to a StringBuilder and returned as String.
     */
    BufferedReader reader = new BufferedReader(new InputStreamReader(is));
    StringBuilder sb = new StringBuilder();

    String line = null;
    try {
        while ((line = reader.readLine()) != null) {
            sb.append(line + "\n");
        }
    } catch (IOException e) {
        e.printStackTrace();
    } finally {
        try {
            is.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    return sb.toString();
}

Android错误：java.net.SocketException：Socket已关闭

5 个答案: