扩展 AsyncTask 的自定义类存在一些问题。我的应用程序面向 Android 4.0.3，下面的代码适用于 30 多人测试它。但是，当我像下面这样调用 new AsyncRequest 时，有两个用户看到应用程序崩溃。
我有一个工作记录器，它正在记录到用户存储上的文本文件中，并且不记录 AsyncRequest 构造函数中的条目。所以我必须假设崩溃是在调用构造函数之前发生的。
遇到此崩溃的两台设备之一显然正在运行 Android 4.0.4。不确定其他设备正在运行什么。不幸的是，我无法访问这两个设备，因此看不到 logcat 输出。
任何关于对象创建导致崩溃的原因的输入将不胜感激。
String url = "www.google.com";
new AsyncRequest(callback, context).executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR, url);
这是完整的 AsyncRequest 类
public class AsyncRequest extends AsyncTask<String, String, String>{
HttpURLConnection connection;
InputStream inStream;
IApiCallback callback;
Context context_;
public AsyncRequest(IApiCallback callback, Context context) {
// Log entry added for testing. Never gets called.
FileLogger.getFileLogger(context).ReportInfo("Enter AsyncRequest Constructor");
this.callback = callback;
context_ = context;
}
@Override
protected String doInBackground(String... uri) {
try {
URL url = new URL(uri[0] + "?format=json");
FileLogger.getFileLogger(context_).ReportInfo("Async Request: Sending HTTP GET to " + url);
connection = (HttpURLConnection) url.openConnection();
connection.setConnectTimeout(5000);
connection.setReadTimeout(5000);
connection.addRequestProperty("Accept-Encoding", "gzip");
connection.addRequestProperty("Cache-Control", "no-cache");
connection.connect();
String encoding = connection.getContentEncoding();
// Determine if the stream is compressed and uncompress it if needed.
if (encoding != null && encoding.equalsIgnoreCase("gzip")) {
inStream = new GZIPInputStream(connection.getInputStream());
} else {
inStream = connection.getInputStream();
}
if (inStream != null) {
// process response
BufferedReader br = new BufferedReader(new InputStreamReader(inStream));
StringBuilder sb = new StringBuilder();
String line;
while ((line = br.readLine()) != null) {
sb.append(line);
}
return sb.toString();
}
} catch (SocketTimeoutException e) {
FileLogger.getFileLogger(context_).ReportException("Async Request: SocketTimeoutException", e);
Log.i("AsyncRequest", "Socket Timeout occured");
} catch (MalformedURLException e) {
FileLogger.getFileLogger(context_).ReportException("Async Request: MalformedUrlException", e);
} catch (IOException e) {
FileLogger.getFileLogger(context_).ReportException("Async Request: IOException", e);
Log.i("doInBackground:","IOException");
if (e != null && e.getMessage() != null) {
Log.i("doInBackground:",e.getMessage());
}
} catch (Exception e) {
FileLogger.getFileLogger(context_).ReportException("Async Request: Exception", e);
} finally {
if (connection != null)
connection.disconnect();
}
return null;
}
@Override
protected void onPostExecute(String result) {
if (result != null)
FileLogger.getFileLogger(context_).ReportInfo("Async Request: Response is valid");
else
FileLogger.getFileLogger(context_).ReportInfo("Async Request: Invalid response");
callback.Execute(result);
}
}
编辑：根据下面的评论。
这是我调用自定义 AsyncTask 的完整方法。我创建 AsyncTask 之前的所有日志消息都显示在日志中。没有一个例外。
日志在创建我的 AsyncRequest 之前显示 url 值，并且该 URL 根本没有格式错误。这是我所期待的。
public void GetServerInfoAsync(IApiCallback callback, Context context) throws IllegalArgumentException, Exception {
if (callback == null)
throw new IllegalArgumentException("callback");
if (context == null)
throw new IllegalArgumentException("context");
try {
FileLogger.getFileLogger(context).ReportInfo("Build URL");
String url = GetApiUrl("System/Info");
FileLogger.getFileLogger(context).ReportInfo("Finished building URL");
if (url != null) {
FileLogger.getFileLogger(context).ReportInfo("GetServerInfoAsync: url is " + url);
new AsyncRequest(callback, context).executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR, url);
} else {
FileLogger.getFileLogger(context).ReportError("GetServerInfoAsync: url is null");
}
} catch (IllegalArgumentException iae) {
FileLogger.getFileLogger(context).ReportException("GetServerInfoAsync: IllegalArgumentException", iae);
throw iae;
} catch (Exception e) {
FileLogger.getFileLogger(context).ReportException("GetServerInfoAsync: Exception", e);
throw e;
}
}