我在SQLite(Android)中获得了数据库对象未关闭异常,但我明确关闭了我的数据库...帮助?

时间:2011-02-09 00:53:04

标签: android sqlite

这是错误:

02-08 16:35:00.899:ERROR / Database(468):android.database.sqlite.DatabaseObjectNotClosedException:应用程序未关闭此处打开的游标或数据库对象

除此之外,我是。以下是发生此问题的方法:

    public static void getUpdates(String username, Context context) {
    HttpClient httpClient = new DefaultHttpClient();
    HttpPost httpPost = new HttpPost("http://10.0.2.2/tag/appgetfriendinfo.php");

    try {
        List<NameValuePair> nVPs = new ArrayList<NameValuePair>();
        nVPs.add(new BasicNameValuePair("username", username));

        httpPost.setEntity(new UrlEncodedFormEntity(nVPs));
        HttpResponse response = httpClient.execute(httpPost);

        ResponseHandler<String> rHandler = new BasicResponseHandler();
        String result = rHandler.handleResponse(response);

        JSONArray jArray = new JSONArray(result);
        for(int i = 0; i < jArray.length(); i++) {
            JSONObject jObj = jArray.getJSONObject(i);
            String userCheck = jObj.getString("username");
            TagDBAdapter dbHelper = new TagDBAdapter(context);
            dbHelper.open();//OPENING THE DATABASE
            Contact contact = new Contact();

            String first = jObj.getString("firstname");
            String last = jObj.getString("lastname");
            String name = first + " " + last;

            contact.setUsername(jObj.getString("username"));
            contact.setFirstName(first);
            contact.setLastName(last);
            contact.setName(name);
            contact.setPhoneNumber(jObj.getString("phonenumber"));
            contact.setEmail(jObj.getString("email"));
            contact.setHomePhone(jObj.getString("homephone"));
            contact.setWorkPhone(jObj.getString("workphone"));

            if(dbHelper.checkForExisting(userCheck) == true) {
                dbHelper.createContact(contact);
            }
            else {
                dbHelper.updateContactAuto(userCheck, contact);
            }
            dbHelper.close();//CLOSING THE DATABASE
        }

    } catch(ClientProtocolException e) {
        Log.e("GETUPDATES", "CPE", e);
        e.printStackTrace();
    } catch(IOException e) {
        Log.e("GETUPDATES", "IOE", e);
        e.printStackTrace();
    } catch(JSONException e) {
        Log.e("GETUPDATES", "JSONE", e);
        e.printStackTrace();
    }
}

正如你在//评论中注意到的那样,我正在打开并关闭数据库,但我仍然收到错误。这是奇怪的,但错误的来源是在SQLite的open()方法中。

错误/数据库(468):at com.tagapp.android.TagDBAdapter.open(TagDBAdapter.java:62)

这是:

    /**THESE ARE MY DBADAPTER'S OPEN AND CLOSE METHODS*/

    public TagDBAdapter open() throws SQLException {
    mDBHelper = new DatabaseHelper(m_context);
    mDb = mDBHelper.getWritableDatabase();
    return this;
}

public void close() {
    mDBHelper.close();
}

这些直接来自Google的记事本教程,他们在不同的情况下为我100%工作。有没有人知道这里发生了什么?非常感谢。

2 个答案:

答案 0 :(得分:12)

问题不在于数据库对象,而是光标 - 你在某处有一个打开的光标。

确保在关闭数据库之前关闭所有游标。 (顺便说一句,如果你想要花哨,可以创建一个ContentProvider,使用SQLiteOpenHelper而不用担心关闭它。)

答案 1 :(得分:0)

在调查类似问题时,请仔细研究。我注意到的一种可能性是,如果你因为任何原因在循环中抛出异常,那么即使你正确处理它,你也会退出循环而最后一个open()永远不会有相应的关闭。 要解决此问题,您需要将close()语句放在finally {}块中。此外,我没有看到为循环的每次迭代创建和打开新游标的任何理由。将它移到循环外面,这样只有一个open()和相应的close()是finally块中的那个。 (或者你可以在循环中使用另一个try-catch构造,这样close()总是会运行。)

示例:

public static void getUpdates(String username, Context context) {
HttpClient httpClient = new DefaultHttpClient();
HttpPost httpPost = new HttpPost("http://10.0.2.2/tag/appgetfriendinfo.php");
TagDBAdapter dbHelper;  // DECLARE THIS HERE SO IT CAN BE ACCESSED OUTSIDE OF try BLOCK
try {
    List<NameValuePair> nVPs = new ArrayList<NameValuePair>();
    nVPs.add(new BasicNameValuePair("username", username));

    httpPost.setEntity(new UrlEncodedFormEntity(nVPs));
    HttpResponse response = httpClient.execute(httpPost);

    ResponseHandler<String> rHandler = new BasicResponseHandler();
    String result = rHandler.handleResponse(response);

    JSONArray jArray = new JSONArray(result);

    // MOVED TO OUTSIDE OF LOOP
    dbHelper = new TagDBAdapter(context);
    dbHelper.open();//OPENING THE DATABASE
    for(int i = 0; i < jArray.length(); i++) {
        JSONObject jObj = jArray.getJSONObject(i);
        String userCheck = jObj.getString("username");
        Contact contact = new Contact();

        String first = jObj.getString("firstname");
        String last = jObj.getString("lastname");
        String name = first + " " + last;

        contact.setUsername(jObj.getString("username"));
        contact.setFirstName(first);
        contact.setLastName(last);
        contact.setName(name);
        contact.setPhoneNumber(jObj.getString("phonenumber"));
        contact.setEmail(jObj.getString("email"));
        contact.setHomePhone(jObj.getString("homephone"));
        contact.setWorkPhone(jObj.getString("workphone"));

        if(dbHelper.checkForExisting(userCheck) == true) {
            dbHelper.createContact(contact);
        }
        else {
            dbHelper.updateContactAuto(userCheck, contact);
        }
    }

} catch(ClientProtocolException e) {
    Log.e("GETUPDATES", "CPE", e);
    e.printStackTrace();
} catch(IOException e) {
    Log.e("GETUPDATES", "IOE", e);
    e.printStackTrace();
} catch(JSONException e) {
    Log.e("GETUPDATES", "JSONE", e);
    e.printStackTrace();
} finally {
    dbHelper.close();//CLOSING THE DATABASE
}

}