private static IConfigurationSet GetConfigurationSet(string filename)
        {
            ConfigurationSet configurationSet = null;
            Hashtable        configColl       = null;


            try
            {
                //The ConfigurationFactory instance is a singleton, it will be instantiated at this point only if it does not already exist.
                // call to create instance of the signleton
                CreateInstance();
            }
            catch (Exception ex)
            {
                throw new Exception(
                          String.Format("Error occured while calling to get the ConfigurationFactory instance in ConfigurationFactory.GetConfigurationSet :{0}"
                                        , ex.Message));
            }

            try
            {
                //Creating ConfigurationSet with filename if not already created.

                configColl = m_Instance.m_configCollRepository;
                if (!configColl.Contains(filename))
                {
                    lock (configColl)
                    {
                        if (!configColl.Contains(filename))
                        {
                            configurationSet = new ConfigurationSet(filename);
                            configColl.Add(filename, configurationSet);
                        }
                    }
                }

                configurationSet = configColl[filename] as ConfigurationSet;
            }
            catch (Exception ex)
            {
                throw new Exception(
                          String.Format("Error occured initializing Creating ConfigurationSet. in ConfigurationFactory.GetConfigurationSet :{0}"
                                        , ex.Message));
            }

            return(configurationSet);
        }
        private static IConfigurationSet GetConfigurationSet(string filename)
        {
            ConfigurationSet configurationSet = null;
            Hashtable configColl = null;

            try
            {
                //The ConfigurationFactory instance is a singleton, it will be instantiated at this point only if it does not already exist.
                // call to create instance of the signleton
                CreateInstance();
            }
            catch (Exception ex)
            {
                throw new Exception(
                    String.Format("Error occured while calling to get the ConfigurationFactory instance in ConfigurationFactory.GetConfigurationSet :{0}"
                        , ex.Message));
            }

            try
            {
                //Creating ConfigurationSet with filename if not already created.

                configColl = m_Instance.m_configCollRepository;
                if(!configColl.Contains(filename))
                {
                    lock (configColl)
                    {
                        if (!configColl.Contains(filename))
                        {
                            configurationSet = new ConfigurationSet(filename);
                            configColl.Add(filename, configurationSet);
                        }
                    }
                }

                configurationSet = configColl[filename] as ConfigurationSet;
            }
            catch(Exception ex)
            {
                throw new Exception(
                 String.Format("Error occured initializing Creating ConfigurationSet. in ConfigurationFactory.GetConfigurationSet :{0}"
                     , ex.Message));
            }

            return configurationSet;
        }