qt实现mysql数据库连接池

#include <QCoreApplication>
#include <QtSql>
#include <QQueue>
#include <QMutex>

class ConnectionPool
{
public:
    static QSqlDatabase getConnection()
    {
        QMutexLocker locker(&mutex);
        if (connections.isEmpty()) {
            // 创建新的数据库连接
            QSqlDatabase db = QSqlDatabase::addDatabase("QMYSQL");
            db.setHostName("localhost");
            db.setPort(3306);
            db.setDatabaseName("mydatabase");
            db.setUserName("username");
            db.setPassword("password");
            if (!db.open()) {
                qDebug() << "Failed to connect to database.";
            }
            return db;
        }
        // 从连接池中获取连接
        return connections.dequeue();
    }

    static void releaseConnection(QSqlDatabase connection)
    {
        QMutexLocker locker(&mutex);
        // 将连接放回连接池
        connections.enqueue(connection);
    }

private:
    static QQueue<QSqlDatabase> connections;
    static QMutex mutex;
};

QQueue<QSqlDatabase> ConnectionPool::connections;
QMutex ConnectionPool::mutex;

int main(int argc, char *argv[])
{
    QCoreApplication a(argc, argv);

    // 使用数据库连接池获取数据库连接
    QSqlDatabase db = ConnectionPool::getConnection();
    // 执行数据库操作...
    ConnectionPool::releaseConnection(db);

    return a.exec();
}