【发布时间】：2013-01-07 05:10:09
【问题描述】：
我正在尝试执行某些操作，例如在应用程序初始启动时创建一个表并插入 720 行，这需要一些时间，所以我决定在后台运行它。请看下面的代码，
MainActivity.java
DatabaseHandler dbhandler = new DatabaseHandler(this);
this.progressDialog = ProgressDialog.show(this, "Please wait...",
"Downloading Passengers Information...", true, false);
new DownloadTask().execute();
private class DownloadTask extends AsyncTask<String, Void, Object> {
@Override
protected Object doInBackground(String... args) {
for (int i = 1; i <= 5; i++) {
for (int j = 0; j < 11; j++) {
value = jedis.hget("passengerInfo",
String.valueOf(i + (char) (asciiA) + j)); //this will get the data from hash table passengerInfo created in Redis
if (value != null) {
addSeat = String.valueOf(i + (char) (asciiA) + j);
paxInfo = value.split(",");
passName = paxInfo[0];
passAge = Integer.parseInt(paxInfo[1]);
passGender = Integer.parseInt(paxInfo[2]);
passFoodPref = paxInfo[3];
dbhandler.addPassengerInfo(new PassengerInfo(addSeat,
passName, passAge, passGender, passFoodPref));
}
else {
addSeat = String.valueOf(i + (char) (asciiA) + j);
passName = "NA";
passAge = 0;
passGender = -1;
passFoodPref = "NA";
dbhandler.addPassengerInfo(new PassengerInfo(addSeat,
passName, passAge, passGender, passFoodPref));
}
}
}
return null;
}
@Override
protected void onPostExecute(Object result) {
// Pass the result data back to the main activity
MainActivity.this.data = result;
if (MainActivity.this.progressDialog != null) {
MainActivity.this.progressDialog.dismiss();
}
}
}
当我运行它时，它会在 logcat 中显示以下错误，
01-23 21:29:06.206: E/AndroidRuntime(704): FATAL EXCEPTION: AsyncTask #1
01-23 21:29:06.206: E/AndroidRuntime(704): java.lang.RuntimeException: An error occured while executing doInBackground()
请帮忙！
仅供参考：整个 Logcat
01-23 21:53:15.807: E/AndroidRuntime(742): 在 android.os.AsyncTask$3.done(AsyncTask.java:200) 01-23 21:53:15.807: E/AndroidRuntime(742): 在 java.util.concurrent.FutureTask$Sync.innerSetException(FutureTask.java:274) 01-23 21:53:15.807: E/AndroidRuntime(742): 在 java.util.concurrent.FutureTask.setException(FutureTask.java:125) 01-23 21:53:15.807: E/AndroidRuntime(742): 在 java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:308) 01-23 21:53:15.807: E/AndroidRuntime(742): 在 java.util.concurrent.FutureTask.run(FutureTask.java:138) 01-23 21:53:15.807: E/AndroidRuntime(742): 在 java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1088) 01-23 21:53:15.807: E/AndroidRuntime(742): 在 java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:581) 01-23 21:53:15.807: E/AndroidRuntime(742): 在 java.lang.Thread.run(Thread.java:1019) 01-23 21:53:15.807: E/AndroidRuntime(742): 原因: redis.clients.jedis.exceptions.JedisConnectionException: java.net.SocketTimeoutException: 连接超时 01-23 21:53:15.807: E/AndroidRuntime(742): 在 redis.clients.jedis.Connection.connect(Connection.java:134) 01-23 21:53:15.807: E/AndroidRuntime(742): 在 redis.clients.jedis.BinaryClient.connect(BinaryClient.java:69) 01-23 21:53:15.807: E/AndroidRuntime(742): 在 redis.clients.jedis.Connection.sendCommand(Connection.java:79) 01-23 21:53:15.807: E/AndroidRuntime(742): 在 redis.clients.jedis.BinaryClient.hget(BinaryClient.java:212) 01-23 21:53:15.807: E/AndroidRuntime(742): 在 redis.clients.jedis.Client.hget(Client.java:138) 01-23 21:53:15.807: E/AndroidRuntime(742): 在 redis.clients.jedis.Jedis.hget(Jedis.java:680) 01-23 21:53:15.807: E/AndroidRuntime(742): 在 android.jedisconnectiontest.com.MainActivity$DownloadTask.doInBackground(MainActivity.java:118) 01-23 21:53:15.807: E/AndroidRuntime(742): 在 android.jedisconnectiontest.com.MainActivity$DownloadTask.doInBackground(MainActivity.java:1) 01-23 21:53:15.807: E/AndroidRuntime(742): 在 android.os.AsyncTask$2.call(AsyncTask.java:185) 01-23 21:53:15.807: E/AndroidRuntime(742): 在 java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:306) 01-23 21:53:15.807: E/AndroidRuntime(742): ... 4 更多 01-23 21:53:15.807：E/AndroidRuntime(742)：原因：java.net.SocketTimeoutException：连接超时 01-23 21:53:15.807: E/AndroidRuntime(742): at org.apache.harmony.luni.platform.OSNetworkSystem.connect(Native Method) 01-23 21:53:15.807: E/AndroidRuntime(742): 在 dalvik.system.BlockGuard$WrappedNetworkSystem.connect(BlockGuard.java:357) 01-23 21:53:15.807: E/AndroidRuntime(742): at org.apache.harmony.luni.net.PlainSocketImpl.connect(PlainSocketImpl.java:204) 01-23 21:53:15.807: E/AndroidRuntime(742): at org.apache.harmony.luni.net.PlainSocketImpl.connect(PlainSocketImpl.java:437) 01-23 21:53:15.807: E/AndroidRuntime(742): 在 java.net.Socket.connect(Socket.java:983) 01-23 21:53:15.807: E/AndroidRuntime(742): 在 redis.clients.jedis.Connection.connect(Connection.java:129) 01-23 21:53:15.807: E/AndroidRuntime(742): ... 13 更多 01-23 21:53:17.737: E/WindowManager(742): Activity android.jedisconnectiontest.com.MainActivity 泄露了最初添加在这里的窗口 com.android.internal.policy.impl.PhoneWindow$DecorView@40523ac8 01-23 21:53:17.737: E/WindowManager(742): android.view.WindowLeaked: Activity android.jedisconnectiontest.com.MainActivity 泄露了窗口 com.android.internal.policy.impl.PhoneWindow$DecorView@40523ac8最初添加在这里 01-23 21:53:17.737: E/WindowManager(742): 在 android.view.ViewRoot.(ViewRoot.java:258) 01-23 21:53:17.737: E/WindowManager(742): 在 android.view.WindowManagerImpl.addView(WindowManagerImpl.java:148) 01-23 21:53:17.737: E/WindowManager(742): 在 android.view.WindowManagerImpl.addView(WindowManagerImpl.java:91) 01-23 21:53:17.737: E/WindowManager(742): 在 android.view.Window$LocalWindowManager.addView(Window.java:424) 01-23 21:53:17.737: E/WindowManager(742): 在 android.app.Dialog.show(Dialog.java:241) 01-23 21:53:17.737: E/WindowManager(742): 在 android.app.ProgressDialog.show(ProgressDialog.java:107) 01-23 21:53:17.737: E/WindowManager(742): 在 android.app.ProgressDialog.show(ProgressDialog.java:95) 01-23 21:53:17.737: E/WindowManager(742): 在 android.jedisconnectiontest.com.MainActivity.onCreate(MainActivity.java:56) 01-23 21:53:17.737: E/WindowManager(742): 在 android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047) 01-23 21:53:17.737: E/WindowManager(742): 在 android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1611) 01-23 21:53:17.737: E/WindowManager(742): 在 android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1663) 01-23 21:53:17.737: E/WindowManager(742): 在 android.app.ActivityThread.access$1500(ActivityThread.java:117) 01-23 21:53:17.737: E/WindowManager(742): 在 android.app.ActivityThread$H.handleMessage(ActivityThread.java:931) 01-23 21:53:17.737: E/WindowManager(742): 在 android.os.Handler.dispatchMessage(Handler.java:99) 01-23 21:53:17.737: E/WindowManager(742): 在 android.os.Looper.loop(Looper.java:123) 01-23 21:53:17.737: E/WindowManager(742): 在 android.app.ActivityThread.main(ActivityThread.java:3683) 01-23 21:53:17.737: E/WindowManager(742): 在 java.lang.reflect.Method.invokeNative(Native Method) 01-23 21:53:17.737: E/WindowManager(742): 在 java.lang.reflect.Method.invoke(Method.java:507) 01-23 21:53:17.737: E/WindowManager(742): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839) 01-23 21:53:17.737: E/WindowManager(742): 在 com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597) 01-23 21:53:17.737: E/WindowManager(742): at dalvik.system.NativeStart.main(Native Method)
【问题讨论】：
-
您可能想发布整个 logcat 错误输出。
-
一旦
doInBackground()完成执行（修复后），下一个问题是data将始终为空，因为您只有来自doInBackground()的return null -
Caused by: redis.clients.jedis.exceptions.JedisConnectionException: java.net.SocketTimeoutException: Connection timed out在我看来.hget(...)不仅从哈希图/哈希表中检索数据，而且从某种服务器中获取它们 -
@A--C 但我不想返回任何数据，所以我给了 null。如果不是 null 那我应该返回什么？
-
@A--C, Tedil, snapix - 是的！你是正确的。问题在于连接。我应该打我的脸，因为我给了错误的IP地址来连接redis！！！