1 /*

     2  * Copyright (c) 2009 Nokia Corporation and/or its subsidiary(-ies).

     3  * All rights reserved.

     4  * This component and the accompanying materials are made available

     5  * under the terms of "Eclipse Public License v1.0"

     6  * which accompanies this distribution, and is available

     7  * at the URL "http://www.eclipse.org/legal/epl-v10.html".

     8  *

     9  * Initial Contributors:

    10  * Nokia Corporation - initial contribution.

    11  *

    12  * Contributors:

    13  *

    14  * Description:  contentinfodb .

    15  *

    16  */

    17 #ifndef CONTENTINFODB_H

    18 #define CONTENTINFODB_H

    19 #include <qobject.h>

    20 #include <QSqlDatabase>

    21 #include <qmutex.h>

    22 #include "contentinfodbcommon.h"

    23 CONTENTINFODB_CLASS(ContentinfodbTest)

    24 

    25 class ContentInfoDb : public QObject

    26     {

    27 Q_OBJECT

    28 public:

    29     /**

    30      * Singleton construtor

    31      * @since S60 ?S60_version.

    32      */

    33     static ContentInfoDb* instance()

    34         {

    35         static QMutex mutex;

    36         if (!m_instance)

    37             {

    38             mutex.lock();

    39             m_instanceCounter++;

    40             if (!m_instance)

    41                 {

    42                 m_instance = new ContentInfoDb;

    43                 }

    44             mutex.unlock();

    45             }

    46 

    47         return m_instance;

    48         }

    49 

    50     /**

    51      * Singleton destructor

    52      * @since S60 ?S60_version.

    53      */

    54     static void deleteinstance()

    55         {

    56         m_instanceCounter--;

    57         if ((m_instanceCounter <= 0) && (m_instance))

    58             {

    59             delete m_instance;

    60             m_instance = 0;

    61             }

    62         }

    63 private:

    64     /**

    65      * Constructor.

    66      * @since S60 ?S60_version.

    67      */

    68     ContentInfoDb();

    69 

    70     /**

    71      * Destructor.

    72      * @since S60 ?S60_version.

    73      */

    74     ~ContentInfoDb();

    75 public:

    76 

    77     /**

    78      * returns success/failure status.

    79      * @since S60 ?S60_version.

    80      * @param query

    81      */

    82     bool writeData(QString query);

    83 

    84     /**

    85      * returns success/failure status.

    86      * @since S60 ?S60_version.

    87      * @param query input

    88      */

    89     QStringList readData(QString query);

    90 

    91     /**

    92      * returns value at mentioned position

    93      * @param query input     

    94      */

    95     QString readStringData(QString query);

    96 

    97     /**

    98      * creates the table with the mentioned tablename.

    99      * @param tablename 

   100      * @param sql query

   101      */

   102     void createTable(QString tablename, QString query);

   103 

   104     /**

   105      * returns success/failure status.

   106      * @since S60 ?S60_version.

   107      */

   108     bool Open();

   109 

   110     /**     

   111      * close the database connection

   112      * @since S60 ?S60_version.     

   113      */

   114     void Close();

   115 

   116 signals:

   117 

   118     /**     

   119      * signal to notify when updation happens in the contentinfodb

   120      */

   121     void dbUpdated();

   122 

   123 private:

   124 

   125     /**

   126      * static instance to make single instance

   127      * Own.

   128      */

   129     static ContentInfoDb *m_instance;

   130 

   131     /**

   132      * counter for number for instance

   133      * Own.

   134      */

   135     static int m_instanceCounter;

   136 

   137     /**

   138      * database handle

   139      * Own.

   140      */

   141     QSqlDatabase m_db;

   142 

   143 private:

   144     CONTENTINFODB_FRIEND_CLASS(ContentinfodbTest)

   145     };

   146 #endif //CONTENTINFODB_H