错误无法执行此操作,因为已关闭连接池

Question

我正在使用sqlite db并使用Alex LockWood的一些代码正确管理您的SQLite数据库

它工作得很好但有时我得到错误"java.lang.IllegalStateException: Cannot perform this operation because the connection pool has been closed." 这是完整的错误:

02-20 16:37:21.385: W/dalvikvm(25730): threadid=13: thread exiting with uncaught exception (group=0x41c122a0)
02-20 16:37:21.390: E/AndroidRuntime(25730): FATAL EXCEPTION: Timer-0
02-20 16:37:21.390: E/AndroidRuntime(25730): java.lang.IllegalStateException: Cannot perform this operation because the connection pool has been closed.
02-20 16:37:21.390: E/AndroidRuntime(25730):    at android.database.sqlite.SQLiteConnectionPool.throwIfClosedLocked(SQLiteConnectionPool.java:963)
02-20 16:37:21.390: E/AndroidRuntime(25730):    at android.database.sqlite.SQLiteConnectionPool.waitForConnection(SQLiteConnectionPool.java:678)
02-20 16:37:21.390: E/AndroidRuntime(25730):    at android.database.sqlite.SQLiteConnectionPool.acquireConnection(SQLiteConnectionPool.java:349)
02-20 16:37:21.390: E/AndroidRuntime(25730):    at android.database.sqlite.SQLiteSession.acquireConnection(SQLiteSession.java:894)
02-20 16:37:21.390: E/AndroidRuntime(25730):    at android.database.sqlite.SQLiteSession.executeForCursorWindow(SQLiteSession.java:834)
02-20 16:37:21.390: E/AndroidRuntime(25730):    at android.database.sqlite.SQLiteQuery.fillWindow(SQLiteQuery.java:62)
02-20 16:37:21.390: E/AndroidRuntime(25730):    at android.database.sqlite.SQLiteCursor.fillWindow(SQLiteCursor.java:143)
02-20 16:37:21.390: E/AndroidRuntime(25730):    at android.database.sqlite.SQLiteCursor.getCount(SQLiteCursor.java:133)
02-20 16:37:21.390: E/AndroidRuntime(25730):    at com.uit.pokemon.DatabaseHandler.getStadiumStatusById(DatabaseHandler.java:533)
02-20 16:37:21.390: E/AndroidRuntime(25730):    at playground.RoomActivity.checkTable(RoomActivity.java:276)
02-20 16:37:21.390: E/AndroidRuntime(25730):    at playground.RoomActivity$6.run(RoomActivity.java:321)
02-20 16:37:21.390: E/AndroidRuntime(25730):    at java.util.Timer$TimerImpl.run(Timer.java:284)
02-20 16:37:21.460: I/timertask cancel(25730): canceled

这是导致错误的代码:

public int getStadiumStatusById(int dataStadiumId){
        SQLiteDatabase db = this.getReadableDatabase();
        Cursor cur = db.rawQuery("SELECT " + keyStadiumId + " as _id, "
                + keyRoomName + ", " + keyP1Name + ", " + keyP1PokemonName
                + ", " + keyP1PokemonLevel + ", " + keyP1PokemonHp + ", "
                + keyP2Name + ", " + keyP2PokemonName + ", "
                + keyP2PokemonLevel + ", " + keyP2PokemonHp + ", "
                + keyTimeCreate + ", " + keyStadiumStatus + " from "
                + tbl_stadium + " WHERE " + keyStadiumId + " = " + "'"
                + dataStadiumId + "'", new String[] {});

        int stadiumStatus = 0;
        if(cur.getCount()>0)
        {
        cur.moveToFirst();
        stadiumStatus = cur.getInt(11);
        }
        db.close();
        cur.close();
        return stadiumStatus;
    }

我试着谷歌搜索了好几个小时但没有结果.请帮我修理一下.任何帮助将不胜感激.谢谢!

Answer 1

称呼

db.open()

在这一行之后：

SQLiteDatabase db = this.getReadableDatabase();

然而，我个人不知道this.getReadableDatabase()到底是怎么做的，但我只想制作自己的数据库适配器。有关更多详细信息，请参阅此链接：http://www.vogella.com/articles/AndroidSQLite/article.html