java.lang.IllegalStateException：无法执行此操作，因为没有当前事务

Question

我创建了一个AsyncTask类，其中编写了这一部分（onPreExecute和doInBackgrond方法）：

@Override
protected void onPreExecute() {
    // Instantiate ProgressDialog and Set style to STYLE_HORIZONTAL
    dialog = new ProgressDialog(context);
    dialog.setIndeterminate(false);
    dialog.setMax(100);
    dialog.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
    dialog.setCancelable(false);
    dialog.setTitle("Update");
    dialog.setMessage("Download data. Please wait...");
    dialog.show();

    super.onPreExecute();
}

@Override
protected String doInBackground(String... urls) {
    int count = 0;
    int numUsers = 0;
    db = new Database(context);
    SQLiteDatabase localDB = db.getWritableDatabase();

    try {   
        JSONArray UserJsonArray = connectAndCreateJsonArray(urls[0]);

        numUsers = UserJsonArray.length();

        localDB.beginTransaction();

        for (int i = 0; i < numUsers; i++) {
            JSONObject jObj = (JSONObject) UserJsonArray.getJSONObject(i);

            localDB.insert("Users", null, getParsedUserEntry(jObj));

            count++;
            publishProgress(count * 100 / numUsers);
        }

        localDB.setTransactionSuccessful();

    } catch (IllegalStateException e) {
        e.printStackTrace();                
    } catch (JSONException e) {
        e.printStackTrace();
        Log.e("Msg", "catch");
    } finally {
        localDB.endTransaction();
    }

    return numUsers+"";
}

private JSONArray connectAndCreateJsonArray(String url) {
    JSONArray jsonArray = new JSONArray();

    HttpClient client = new DefaultHttpClient();
    HttpGet request = new HttpGet("http://www.example.com/file.json");
    request.addHeader("Cache-Control", "no-cache");

    try {
        HttpResponse response = client.execute(request);
        HttpEntity entity = response.getEntity();
        InputStreamReader in = new InputStreamReader(entity.getContent());
        BufferedReader reader = new BufferedReader(in);
        StringBuilder stringBuilder = new StringBuilder();
        String line = "";

        while ((line=reader.readLine()) != null) {
            stringBuilder.append(line);
        }

        jsonArray = new JSONArray(stringBuilder.toString());

    } catch (SocketTimeoutException e) {
        e.printStackTrace();
    } catch (SocketException e) {
        e.printStackTrace();
    } catch (IllegalStateException e) {
        e.printStackTrace();                
    } catch (ClientProtocolException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
    } catch (JSONException e) {
        e.printStackTrace();
    }

    return jsonArray;
}

我一直工作得很好，但是今天在将某些内容修改为其他类之后，并从Android SDK Manager安装了2个软件包后，它停止工作了。 （我安装了Android SDK Build-Tools v20和Android SDK Tools到版本23.0.5）。

现在我收到此错误： java.lang.IllegalStateException：无法执行此操作，因为没有当前事务

这是我的LogCat：

10-13 02:11:36.700: E/AndroidRuntime(31210): FATAL EXCEPTION: AsyncTask #1
10-13 02:11:36.700: E/AndroidRuntime(31210): Process: com.example.myapp, PID: 31210
10-13 02:11:36.700: E/AndroidRuntime(31210): java.lang.RuntimeException: An error occured while executing doInBackground()
10-13 02:11:36.700: E/AndroidRuntime(31210):    at android.os.AsyncTask$3.done(AsyncTask.java:300)
10-13 02:11:36.700: E/AndroidRuntime(31210):    at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:355)
10-13 02:11:36.700: E/AndroidRuntime(31210):    at java.util.concurrent.FutureTask.setException(FutureTask.java:222)
10-13 02:11:36.700: E/AndroidRuntime(31210):    at java.util.concurrent.FutureTask.run(FutureTask.java:242)
10-13 02:11:36.700: E/AndroidRuntime(31210):    at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:231)
10-13 02:11:36.700: E/AndroidRuntime(31210):    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
10-13 02:11:36.700: E/AndroidRuntime(31210):    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
10-13 02:11:36.700: E/AndroidRuntime(31210):    at java.lang.Thread.run(Thread.java:841)
10-13 02:11:36.700: E/AndroidRuntime(31210): Caused by: java.lang.IllegalStateException: Cannot perform this operation because there is no current transaction.
10-13 02:11:36.700: E/AndroidRuntime(31210):    at android.database.sqlite.SQLiteSession.throwIfNoTransaction(SQLiteSession.java:915)
10-13 02:11:36.700: E/AndroidRuntime(31210):    at android.database.sqlite.SQLiteSession.endTransaction(SQLiteSession.java:398)
10-13 02:11:36.700: E/AndroidRuntime(31210):    at android.database.sqlite.SQLiteDatabase.endTransaction(SQLiteDatabase.java:522)
10-13 02:11:36.700: E/AndroidRuntime(31210):    at com.example.myapp.DownloadDataFromServer.doInBackground(DownloadDataFromServer.java:114)
10-13 02:11:36.700: E/AndroidRuntime(31210):    at com.example.myapp.DownloadDataFromServer.doInBackground(DownloadDataFromServer.java:1)
10-13 02:11:36.700: E/AndroidRuntime(31210):    at android.os.AsyncTask$2.call(AsyncTask.java:288)
10-13 02:11:36.700: E/AndroidRuntime(31210):    at java.util.concurrent.FutureTask.run(FutureTask.java:237)
10-13 02:11:36.700: E/AndroidRuntime(31210):    ... 4 more
10-13 02:11:37.765: E/WindowManager(31210): android.view.WindowLeaked: Activity com.example.myapp.Main has leaked window com.android.internal.policy.impl.PhoneWindow$DecorView{420f12e8 V.E..... R....... 0,0-480,322} that was originally added here
10-13 02:11:37.765: E/WindowManager(31210):     at android.view.ViewRootImpl.<init>(ViewRootImpl.java:346)
10-13 02:11:37.765: E/WindowManager(31210):     at android.view.WindowManagerGlobal.addView(WindowManagerGlobal.java:248)
10-13 02:11:37.765: E/WindowManager(31210):     at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:69)
10-13 02:11:37.765: E/WindowManager(31210):     at android.app.Dialog.show(Dialog.java:286)
10-13 02:11:37.765: E/WindowManager(31210):     at com.example.myapp.DownloadDataFromServer.onPreExecute(DownloadDataFromServer.java:49)
10-13 02:11:37.765: E/WindowManager(31210):     at android.os.AsyncTask.executeOnExecutor(AsyncTask.java:587)
10-13 02:11:37.765: E/WindowManager(31210):     at android.os.AsyncTask.execute(AsyncTask.java:535)
10-13 02:11:37.765: E/WindowManager(31210):     at com.example.myapp.Main.onOptionsItemSelected(Main.java:151)
10-13 02:11:37.765: E/WindowManager(31210):     at android.app.Activity.onMenuItemSelected(Activity.java:2600)
10-13 02:11:37.765: E/WindowManager(31210):     at com.android.internal.policy.impl.PhoneWindow.onMenuItemSelected(PhoneWindow.java:1065)
10-13 02:11:37.765: E/WindowManager(31210):     at com.android.internal.view.menu.MenuBuilder.dispatchMenuItemSelected(MenuBuilder.java:741)
10-13 02:11:37.765: E/WindowManager(31210):     at com.android.internal.view.menu.MenuItemImpl.invoke(MenuItemImpl.java:152)
10-13 02:11:37.765: E/WindowManager(31210):     at com.android.internal.view.menu.MenuBuilder.performItemAction(MenuBuilder.java:884)
10-13 02:11:37.765: E/WindowManager(31210):     at com.android.internal.view.menu.MenuBuilder.performItemAction(MenuBuilder.java:874)
10-13 02:11:37.765: E/WindowManager(31210):     at com.android.internal.view.menu.MenuPopupHelper.onItemClick(MenuPopupHelper.java:177)
10-13 02:11:37.765: E/WindowManager(31210):     at android.widget.AdapterView.performItemClick(AdapterView.java:298)
10-13 02:11:37.765: E/WindowManager(31210):     at android.widget.AbsListView.performItemClick(AbsListView.java:1113)
10-13 02:11:37.765: E/WindowManager(31210):     at android.widget.AbsListView$PerformClick.run(AbsListView.java:2911)
10-13 02:11:37.765: E/WindowManager(31210):     at android.widget.AbsListView$3.run(AbsListView.java:3645)
10-13 02:11:37.765: E/WindowManager(31210):     at android.os.Handler.handleCallback(Handler.java:733)
10-13 02:11:37.765: E/WindowManager(31210):     at android.os.Handler.dispatchMessage(Handler.java:95)
10-13 02:11:37.765: E/WindowManager(31210):     at android.os.Looper.loop(Looper.java:136)
10-13 02:11:37.765: E/WindowManager(31210):     at android.app.ActivityThread.main(ActivityThread.java:5146)
10-13 02:11:37.765: E/WindowManager(31210):     at java.lang.reflect.Method.invokeNative(Native Method)
10-13 02:11:37.765: E/WindowManager(31210):     at java.lang.reflect.Method.invoke(Method.java:515)
10-13 02:11:37.765: E/WindowManager(31210):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:732)
10-13 02:11:37.765: E/WindowManager(31210):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:566)
10-13 02:11:37.765: E/WindowManager(31210):     at dalvik.system.NativeStart.main(Native Method)

在第49行上是这样的：

dialog.show();

在线114有这个：

localDB.endTransaction();

这很奇怪...可能是什么问题？ 谢谢。

Answer 1

你可能会打一个异常之前beginTransaction ..move的finally到另一个try块内

try {   
    JSONArray UserJsonArray = connectAndCreateJsonArray(urls[0]);
    numUsers = UserJsonArray.length();
    if (numUsers < 1) return numUsers + "";
    try {  
        localDB.beginTransaction();          
        for (int i = 0; i < numUsers; i++) {
            JSONObject jObj = (JSONObject) UserJsonArray.getJSONObject(i);
            localDB.insert("Users", null, getParsedUserEntry(jObj));
           count++;
           publishProgress(count * 100 / numUsers);
        }
        localDB.setTransactionSuccessful();
    } catch (IllegalStateException e) {
        e.printStackTrace();                
    } catch (JSONException e) {
        e.printStackTrace();
        Log.e("Msg", "catch");
    } catch (Exception e) { // everything else
        e.printStackTrace();
    } finally {
        localDB.endTransaction();
    }
} catch (Exception e) { // everything else
    e.printStackTrace();
}

Answer 2

关于什么

try{
  ...
} catch (Exception e) { // everything else
    e.printStackTrace();
} finally {
    if(localDB != null && localDB.inTransation()){
         localDB.endTransaction();
    }
}

而不是“ ...将最终移动到另一个try块中”？

Answer 3

在您的代码中，如果在localDB.beginTransaction();之前发生异常localDB.beginTransaction(); 那么该事务将不会打开，并且由于您在finally块中尝试关闭该事务，将IllegalStateException （尚未启动事务）。

替换此代码：

try {   
    JSONArray UserJsonArray = connectAndCreateJsonArray(urls[0]);
    numUsers = UserJsonArray.length();

    localDB.beginTransaction();

    for (int i = 0; i < numUsers; i++) {
        JSONObject jObj = (JSONObject) UserJsonArray.getJSONObject(i);
        localDB.insert("Users", null, getParsedUserEntry(jObj));
        count++;
        publishProgress(count * 100 / numUsers);
    }

    localDB.setTransactionSuccessful();
} catch (IllegalStateException e) {
    e.printStackTrace();                
} catch (JSONException e) {
     e.printStackTrace();
    Log.e("Msg", "catch");
} finally {
    localDB.endTransaction();
}

在此代码上：

JSONArray UserJsonArray = connectAndCreateJsonArray(urls[0]);
numUsers = UserJsonArray.length();

localDB.beginTransaction();

try {   
    for (int i = 0; i < numUsers; i++) {
        JSONObject jObj = (JSONObject) UserJsonArray.getJSONObject(i);
        localDB.insert("Users", null, getParsedUserEntry(jObj));
        count++;
        publishProgress(count * 100 / numUsers);
    }

    localDB.setTransactionSuccessful();
} catch (IllegalStateException e) {
    e.printStackTrace();                
} catch (JSONException e) {
     e.printStackTrace();
    Log.e("Msg", "catch");
} finally {
    localDB.endTransaction();
}

如有必要，可以将前两行包装在单独的try-catch 。

Answer 4

我有一个像您一样的错误，这是我的代码：

try {
    String sql = "SELECT * FROM "+DB_TABLEDOWNLOAD;
    Cursor cursor = db.rawQuery(sql, null);
    //空双引号为原表没有的字段
    String temp = "";
    int existIconPath = cursor.getColumnIndex("iconPath");
    int existAudioID = cursor.getColumnIndex("audioID");

    if (existIconPath == -1 && existAudioID == -1){
        temp = "url, downed,total,path,name, audioTitle, audioFileID,\"\",\"\"";
    }else if (existIconPath == -1 && existAudioID != -1){//iconPath不存在
        temp = "url, downed,total,path,name, audioTitle, audioFileID,\"\",audioID";
    }else if (existIconPath != -1 && existAudioID == -1){//audioID不存在
        temp = "url, downed,total,path,name, audioTitle, audioFileID,iconPath,\"\"";
    }else {
        return;
    }

    db.beginTransaction();
    String tempTableName = "_temp_"+DB_TABLEDOWNLOAD;
    String sqlCreateTemp = " ALTER TABLE "+DB_TABLEDOWNLOAD+" RENAME TO "+tempTableName+";";
     db.execSQL(sqlCreateTemp);

     final String TB_TESTPAPERINFO_CREATE = "Create  TABLE IF NOT EXISTS " 
                  + DB_TABLEDOWNLOAD
                  + "(url TEXT, downed TEXT,total TEXT,path TEXT,name TEXT, audioTitle TEXT, audioFileID TEXT,iconPath TEXT, audioID TEXT);";
     db.execSQL(TB_TESTPAPERINFO_CREATE);

     String sqlBackupData = "INSERT INTO "+DB_TABLEDOWNLOAD+" SELECT "+temp+" FROM "+tempTableName+";";
     db.execSQL(sqlBackupData);
     String sqlDrop = "DROP TABLE IF EXISTS '"+tempTableName+"';";
     db.execSQL(sqlDrop);
     db.setTransactionSuccessful();
} catch (Exception e) {
    e.printStackTrace();
}finally{
    db.endTransaction();
}

我用回之前db.beginTransaction()之前我的代码返回beginTransaction ，但我endTransaction在finally 。 如果您没有beginTransaction和endTransaction ，则会出现异常。