AbstractDao.cpp

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#include "AbstractDao.h"
#include "SpikeStreamDBException.h"
using namespace spikestream;

//Qt includes
#include <QDebug>

//Declare static variables
unsigned int AbstractDao::dbCounter = 0;


AbstractDao::AbstractDao(const DBInfo& dbInfo){
    //Store the information about the database
    this->dbInfo = dbInfo;

    //Default name of database  - this changes when it is connected.
    dbName = "";

        //Initialize dbThread to NULL
        dbThread = NULL;

    //Connect to the database
    connectToDatabase();
}


AbstractDao::AbstractDao(){
        //Default name of database  - this changes when it is connected.
        dbName = "";
}


AbstractDao::~AbstractDao(){
    closeDatabaseConnection();
}


/*----------------------------------------------------------*/
/*-----                 PUBLIC METHODS                 -----*/
/*----------------------------------------------------------*/

DBInfo AbstractDao::getDBInfo(){
    return dbInfo;
}


QThread* AbstractDao::getThread(){
        return dbThread;
}


/*----------------------------------------------------------*/
/*-----               PROTECTED METHODS                -----*/
/*----------------------------------------------------------*/

void AbstractDao::checkDatabase(){
    if(!isConnected())
                connectToDatabase();

    /* Check that we are accessing datbase connection from the thread it was created on.
       The Qt database class only works within a single thread.*/
    if(QThread::currentThread() != dbThread){
                throw SpikeStreamDBException("Attempting to access database from different thread. This is not supported in Qt4");
    }
}


bool AbstractDao::isConnected(){
    QSqlDatabase db = QSqlDatabase::database(dbName);
    if(db.isValid())
                if(db.isOpen())
                        return true;
    return false;
}


void AbstractDao::closeDatabaseConnection(){
    QSqlDatabase::removeDatabase(dbName);
}


void AbstractDao::connectToDatabase(){
        //Record the thread that this database was created in - this class cannot be used across multiple threads
    dbThread = QThread::currentThread();

    //Get a unique name that can be used to access the database
    dbName = AbstractDao::getUniqueDBName();

    //Create database unique to this thread. No need to store reference because it is held statically
    QSqlDatabase database = QSqlDatabase::addDatabase("QMYSQL", dbName);
    database.setHostName(this->dbInfo.getHost());
    database.setDatabaseName(this->dbInfo.getDatabase());
    database.setUserName(this->dbInfo.getUser());
    database.setPassword(this->dbInfo.getPassword());

    //Set connection options to prevent it from timing out
        database.setConnectOptions("MYSQL_OPT_RECONNECT=1");
    //database.setConnectOptions("CLIENT_SSL=1;CLIENT_IGNORE_SPACE=1");

    //Open database connection
    bool ok = database.open();
    if(!ok)
                throw SpikeStreamDBException( QString("Cannot connect to database ") + this->dbInfo.toString() + ". Error: " + database.lastError().text() );
}


void AbstractDao::executeQuery(QSqlQuery& query){
    bool result = query.exec();
    if(!result){
                throw SpikeStreamDBException(QString("Error executing query: '") + query.lastQuery() + "'; Error='" + query.lastError().text() + "'.");
    }
}


void AbstractDao::executeQuery(const QString& queryStr){
    QSqlQuery query = getQuery(queryStr);
    executeQuery(query);
}


QSqlQuery AbstractDao::getQuery(){
    checkDatabase();
        QSqlQuery tmpQuery(QSqlDatabase::database(dbName));
        tmpQuery.setForwardOnly(true);
        return tmpQuery;
}


QSqlQuery AbstractDao::getQuery(const QString& queryStr){
    checkDatabase();
    QSqlQuery tmpQuery(QSqlDatabase::database(dbName));
        tmpQuery.setForwardOnly(true);
    tmpQuery.prepare(queryStr);
    return tmpQuery;
}


/*----------------------------------------------------------*/
/*-----                 PRIVATE METHODS                -----*/
/*----------------------------------------------------------*/

QString AbstractDao::getUniqueDBName(){
    ++dbCounter;
    return QString("Database-") + QString::number(dbCounter);
}