Hi, Thanks for your replies.
My point here was that using env variables is more and more common to configure apps, and they have less convenient support than system properties (the other way to provide easy external configuration at launch time with key/value). I agree that Objects.requireNonNullElse(System.getEnv(String key), "n/a")); is an easy way to achieve this, but I still think System.getEnv(key, "n/a") should be a good addition. Regards, Loïc Le mar. 16 févr. 2021 à 21:59, Remi Forax <fo...@univ-mlv.fr> a écrit : > ----- Mail original ----- > > De: "Michael Kuhlmann" <j...@fiolino.de> > > À: "core-libs-dev" <core-libs-dev@openjdk.java.net> > > Envoyé: Mardi 16 Février 2021 13:34:30 > > Objet: Re: System.getEnv(String name, String def) > > > Hi Rémi, > > > > I don't want to be pedantic, but I see this as an anti-pattern. You > > would create an Optional just to immediately call orElse() on it. That's > > not how Optional should be used. (But you know that.) > > > > It's described in Recipe 12 of this Java Magazine article, for instance: > > > https://blogs.oracle.com/javamagazine/12-recipes-for-using-the-optional-class-as-its-meant-to-be-used > > yep, you are right. > Optional.ofNullable(...).orElse(...) is not the best pattern in term of > readability. > > > > > Best, > > Michael > > regards, > Rémi > > > > > On 2/15/21 3:09 PM, Remi Forax wrote: > >> Hi Loic, > >> You can use Optional.OfNullable() which is a kind of the general bridge > between > >> the nullable world and the non-nullable one. > >> > >> var fooOptional = Optional.ofNullable(System.getenv("FOO")); > >> var fooValue = fooOptional.orElse(defaultValue); > >> > >> regards, > >> Rémi Forax > >> > >> ----- Mail original ----- > >>> De: "Loïc MATHIEU" <loikes...@gmail.com> > >>> À: "core-libs-dev" <core-libs-dev@openjdk.java.net> > >>> Envoyé: Lundi 15 Février 2021 14:59:42 > >>> Objet: System.getEnv(String name, String def) > >> > >>> Hello, > >>> > >>> I wonder if there has already been some discussion to provide > >>> a System.getEnv(String name, String def) method that allows to return a > >>> default value in case the env variable didn't exist. > >>> > >>> When using system properties instead of env variable, we do have a > >>> System.getProperty(String key, String def) variant. > >>> > >>> Stating the JavaDoc of System.getEnv(): > >>> *System properties and environment variables are both conceptually > mappings > >>> between names and values* > >>> > >>> So if system properties and environment variables are similar concepts, > >>> they should provide the same functionalities right ? > >>> > >>> This would be very convenient as more and more people rely on > >>> environment variables these days to configure their applications. > >>> > >>> Regards, > >>> > > >> Loïc >
