The options defining the property behavior when the multiple flag is set to true.

@see    self::defaultMultipleOptions
@param  string|null $key Optional setting to retrieve from the options.
@return array|mixed|null
343761
public function multipleOptions($key = null)
    {
        if ($this->multipleOptions === null) {
            $this->multipleOptions = $this->defaultMultipleOptions();
        }

        if (is_string($key)) {
            if (isset($this->multipleOptions[$key])) {
                return $this->multipleOptions[$key];
            } else {
                return null;
            }
        }

        return $this->multipleOptions;
    }
966751
protected function getValuesFromKeyMap( $key )
    {
        if ( empty( $key ) || empty( $this->keyMap[$key] ) )
        {
            return null;
        }

        return $this->keyMap[$key];
    }
232420
public function opt($key)
	{
		if($key === NULL || $key === '' || !array_key_exists($key, $this->map))
		{
			return NULL;
		}
		else
		{
			return $this->map[$key];
		}
	}
679493
public function getOptions($key = null)
    {
        if ($key == null) {
            return $this->options;
        } else {
            return $this->options[$key];
        }
    }
453190
public function getSetting($key)
    {
        if (!isset($this->_settings[$key])) {
            return null;
        }
        return $this->_settings[$key];
    }
268912
public function unsetOption($key)
    {
        if ($this->hasOption($key))
            $this->options = array_except($this->options, $key);

        return $this;
    }
1346578
protected function option($key, $default = null)
    {
        return array_key_exists($key, $this->options) ? $this->options[$key] : $default;
    }
937257
public function getConfig($key = null)
	{
		if ($key === null)
		{
			return array_merge($this->configDefaults, $this->config);
		}
		elseif (isset($this->config[$key]))
		{
			return $this->config[$key];
		}
		elseif (isset($this->configDefaults[$key]))
		{
			return $this->configDefaults[$key];
		}

		return null;
	}
442592
public function getOption($key)
    {
        switch ($key) {
            case 'deploymentPath':
                return $this->getDeploymentPath();
            case 'releasesPath':
                return $this->getReleasesPath();
            case 'sharedPath':
                return $this->getSharedPath();
            default:
                return $this->options[$key];
        }
    }
1049293
public function get($key, $default = null)
    {
        if (array_key_exists($key, $this->options)) return $this->valuelize($this->options[$key]);

        foreach ($this->getDefinitions() as $define) {
            // when short option
            if ($key === $define->getShortName()) {
                if (array_key_exists($define->getName(), $this->options)) return $this->valuelize($this->options[$define->getName()]);
                return $this->valuelize($define->getDefault());
            }
            // when long option
            if ($key === $define->getName()) {
                if (array_key_exists($define->getShortName(), $this->options)) return $this->valuelize($this->options[$define->getShortName()]);
                return $this->valuelize($define->getDefault());
            }
        }

        return $this->valuelize($default);
    }
785658
public function config($key, $default = null)
    {
        // if an array is passed as the key, we will assume you want to set an array of values
        if (is_array($key)) {
            return $this->config = array_merge($this->config, $key);
        }

        return array_key_exists($key, $this->config)
                ? $this->config[$key]
                : $default;
    }
33371
public function getOption(string $key)
    {
        if (!\array_key_exists($key, $this->options)) {
            throw new GPGMailerException('Key ' . $key . ' not defined');
        }
        return $this->options[$key];
    }
308213
protected function findSettingByKey(string $key)
    {
        if (!$this->settings && !$this->lazyLoad) {
            $this->settings = $this->settingRepository->all();
        }

        if ($setting = $this->settingsRegistry->get($key)) {
            return [
                'object' => $setting,
                'value'  => $this->settings[$key] ?? $setting->default()
            ];
        }

        return null;
    }
970660
public function defaultSetting($key = null)
    {
        if (!is_null($key)) {
            return $this->settings()->getDefault($key);
        }

        return $this->settings()->allDefaults();
    }
579964
public function getOption($key = null)
    {
        if (is_null($this->options)) {
            $this->preloadDefaults(true);
        }
        
        return $key === null ? $this->options : $this->options[$key];
    }
429421
protected function findPreferenceByKey(string $key)
    {
        if (!$this->preferences && !$this->lazyLoad) {
            $this->preferences = $this->preferenceRepository->all();
        }

        if ($preference = $this->preferencesRegistry->get($key)) {
            return [
                'object' => $preference,
                'value'  => $this->preferences[$key] ?? $preference->default()
            ];
        }

        return null;
    }
705752
protected function option( $key, $default = false ) {
		return ( isset( $this->options[ $key ] ) ) ? $this->options[ $key ] : $default;
	}