java - Android 错误 : java.net.SocketException:套接字已关闭

Question

我看到这个错误每周出现在我的崩溃日志中数百次，但此时我已经花了几周时间试图找出错误但没有成功。我一直无法在我的任何设备上重现它。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"

这是错误来源的代码块...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;
    }

非常感谢任何帮助最终解决这个问题的人!

Answer 1

在我看来，这个问题的罪魁祸首不是您的应用程序，而是远程端(即 HTTP 服务器)。最有可能的是 HTTP 服务器突然重置连接，这会导致您的应用程序中出现 SocketException。在生产环境中，这些事情经常发生。可能是由于 HTTP 服务器过载，某些异常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请求数量增加；服务器也可能耗尽它的本地套接字池......原因可能有几十个)。

如果与成功的 HTTP 请求相比这些错误的比例较低，我不会太担心，我只是将那段代码包装到 try { ... } catch (SocketException e ) { ... } 语句并向用户显示一个对话框，告诉他们请求失败，他们应该重试。

我肯定会做的是尝试确定此行为的原因:我会尝试匹配这些异常之一的时间，并尝试深入研究接近该时间的 HTTP 服务器日志，以尝试确定原因这种突然断开连接(假设您可以访问该日志和其他诊断工具)。正如我之前所说，这可能是一件愚蠢的事情，或者调试起来有点复杂，但我敢打赌这就是问题所在。