Method initFile

/**
 * Method to initialise the log file.  This will create the folder path to the file if it doesn't already
 * exist and also get a new file header if the file doesn't already exist.  If the file already exists it
 * will simply open it for writing.
 *
 * @return  void
 *
 * @since   1.7.0
 * @throws  \RuntimeException
 */
protected function initFile()
{
    // We only need to make sure the file exists
    if (File::exists($this->path)) {
        return;
    }
    // Make sure the folder exists in which to create the log file.
    Folder::create(\dirname($this->path));
    // Build the log file header.
    $head = $this->generateFileHeader();
    if (!File::write($this->path, $head)) {
        throw new \RuntimeException('Cannot write to log file.');
    }
}