Question

我对这段代码有点问题：

public static int localUserIdByServerUserId(int serverUserId, String serverName){

        dbHelper = new DataBaseHelper(context, "opalqnka_sys_tpl.sqlite", null, 1);
        dbHelper.getDatabase();
        dbHelper.executeQuery("users", "objectId", "2");
        dbHelper.executeQuery("users","serverName","opalqnka");
        dbHelper.executeQuery("users", "objectId", "3");
        dbHelper.executeQuery("users","serverName","opalqnka");
        dbHelper.executeQuery("users", "objectId", "3");

        String query = "SELECT id FROM users WHERE objectId = "+serverUserId+" AND serverName = '"+serverName+"' LIMIT 1";
        ArrayList<String> result = new ArrayList<String>();
        cursor = dbHelper.executeSQLQuery(query);
        cursor.moveToFirst();
        while(!cursor.isAfterLast()) {
            result.add(cursor.getString(cursor.getColumnIndex("id")));
             cursor.moveToNext();
        }

        int uuid = Integer.parseInt(result.get(cursor.getInt(cursor.getColumnIndex("id"))));
        Log.w("localUSerByIdServerUserId","LocalUserByIdServerUserId result : "+uuid);
        cursor.close();
        return uuid;
    }

在这一行给我android.database.CursorIndexOutOfBoundsException: Index 0 requested, with a size of 0：

int uuid = Integer.parseInt(result.get(cursor.getInt(cursor.getColumnIndex("id"))));

我对数据库并不熟悉，这就是为什么我在这里问愚蠢的问题。所以，如果有人能解决我的问题，请提前感谢！

Answer 1

首先清楚你想要什么。崩溃的问题发生在结果中没有得到任何价值。首先检查记录添加结果。像这样打印日志

Log.e("",""+result.toString());

如果只有一条记录，你可以这样：

int uuid = Integer.parseInt(result.get(0));

如果有多个记录，您可以使用for循环并获得多个ID：

for(int i=0; i<result.size();i++)
    int uuid = Integer.parseInt(result.get(i));

Answer 2

您可以这样做：

cursor.moveToFirst();
    while(!cursor.isAfterLast()) {
        result.add(cursor.getString(cursor.getColumnIndex("id")));
        cursor.moveToNext();
    }

    Log.i("result ","Result : "+result.toString());
    Log.i("CURSOR ","Cursor Position : "+cursor.getPosition());
    Integer uuid = Integer.parseInt(result.get(cursor.getColumnIndex("id")));

android将sql查询结果保存为游标异常

2 个答案: