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    public class OracleConnectionFactory : IDbConnectionFactory
    {
        private readonly string baseConnectionString;
        private readonly IDictionary<DbConnection, string> connections = new Dictionary<DbConnection, string>();
        private Func<string, DbProviderFactory> providerFactoryCreator;

        public OracleConnectionFactory()
        {
            this.baseConnectionString = "Server=localhost;Sid=XE";
        }

        public OracleConnectionFactory(string baseConnectionString)
        {
            Contract.Requires(baseConnectionString != null);
            this.baseConnectionString = baseConnectionString;
        }

        public string BaseConnectionString
        {
            get
            {
                return this.baseConnectionString;
            }
        }

        internal Func<string, DbProviderFactory> ProviderFactory
        {
            get
            {
                if (this.providerFactoryCreator == null)
                {
                    this.providerFactoryCreator = DbProviderFactories.GetFactory;
                }

                return this.providerFactoryCreator;
            }

            set
            {
                this.providerFactoryCreator = value;
            }
        }

        public DbConnection CreateConnection(string nameOrConnectionString)
        {
            Contract.Assume(!string.IsNullOrWhiteSpace(nameOrConnectionString));

            var connectionString = nameOrConnectionString;
            var name = string.Empty;

            if (nameOrConnectionString.IndexOf('=') == -1)
            {
                connectionString = new OracleConnectionStringBuilder(this.baseConnectionString).ConnectionString;
                name = nameOrConnectionString.ToUpperInvariant();
                var index = name.LastIndexOf('.');
                if (index != -1)
                {
                    var startIndex = index + 1;
                    name = name.Substring(startIndex, name.Length - startIndex);
                }
            }

            DbConnection connection;
            try
            {
                connection = this.ProviderFactory("Devart.Data.Oracle").CreateConnection();
                connection.ConnectionString = connectionString;
            }
            catch
            {
                connection = new OracleConnection(connectionString);
            }

            if (!string.IsNullOrEmpty(name))
            {
                connection.Disposed += this.OnConnectionDisposed;
                connection.StateChange += this.OnConnectionStateChange;

                this.connections.Add(connection, name);
            }

            return connection;
        }

        private void OnConnectionDisposed(object sender, EventArgs e)
        {
            var connection = (DbConnection)sender;
            connection.Disposed -= this.OnConnectionDisposed;
            connection.StateChange -= this.OnConnectionStateChange;
            this.connections.Remove(connection);
        }

        private void OnConnectionStateChange(object sender, StateChangeEventArgs e)
        {
            if (e.CurrentState == ConnectionState.Open)
            {
                var connection = (DbConnection)sender;
                string name;
                if (this.connections.TryGetValue(connection, out name))
                {
                    connection.ChangeDatabase(name);
                }
            }
        }
    }