Performance concern: FileInputStream vs Singleton

Question

For getProperty method I’ve created singleton object since during the run there will be a lot of calls to the property file to retrieve a specific value. Thus, one object will be created and persisted in memory during the program run. Alternative is not to make it as singleton: as result FileInputStream object will be created every time this method is called.

From those 2 approaches which one is considered as more appropriate to use in terms of performance?

   public static String getProperty (String property) {
        if (properties == null) {
            try {
                FileInputStream fis = new FileInputStream(System.getProperty("user.dir")
                        + "//src//main//resources//config.properties");
                properties = new Properties();
                properties.load(fis);
            } catch (IOException e) {
                System.out.println(e.getMessage());
            }
        }

        return properties.getProperty(property);
    }