Accessing the application.conf properties from java class with Play! 2.0

Question

I want to add an object to the Global scope, and in order to construct it I need to pass it a path to a file. I don't want to hard code the file path in the source, and so I want to get that path from the application.conf.

The problem is that I don't know how to access these properties from the java class. I tried this:

Configuration.root().getString("file.path")

But it ends with a NullPointerException.

Am I wrong in assuming that there's a global Configuration instance that I can use? Thanks.

Solution 1

Try Play.application().configuration().getString("your.key")

As noted in the comment (nico_ekito), please use play.Play and not play.api.Play. play.api.Play is for scala controllers (see comment by Marcus biesior Biesioroff)

Additionally, play uses https://github.com/typesafehub/config under the hood so it can also provide some insights.

Solution 2

Even if it seems simple, here is the scala way to get properties from configuration file :

Play 2.0 and 2.1 :

import play.api.Play.current
...
Play.application.configuration.getString("your.key")

Play 2.2 and +

import play.api.Play.current
...
current.configuration.getString("your.key")

Using Typesafe config

import com.typesafe.config.ConfigFactory
...
ConfigFactory.load().getString("your.key");

Solution 3

From Play 2.4 and + it is better to use dependency injection to access Configurations:

import play.Configuration;
import javax.inject.Inject;


@Inject
private Configuration configuration;

...

String value = configuration.getString("your.key");

Solution 4

Since Play 2 uses the Typesafe config library, I accessed my vars in application.conf like this :

ConfigFactory.load().getString("my.var");

Solution 5

In the play java is:

import play.Play;
...
Play.application().configuration().getString("key")

View more solutions

Comments

[Nitzan Tomer]

Thanks, I'm using java though and not scala

[Cyril N.]

Play.application() doesn't exist anymore :/

[ndeverge]

Be careful with the import, do you use play.Play and not play.api.Play ?

[nightograph]

as Cyril N mentioned Play.application() does not exist!

[Nasir]

@nightograph can you elaborate? I just created a brand new 2.0 java project, added the following lines 'String key = Play.application().configuration().getString("key"); return ok(index.render(key));' and added a key in conf file. I get the text value in the conf file.

[biesior]

my Play.application().configuration().getString("key") is still available too. @nightograph and Cyril, could you explain ?

[nightograph]

@MarcusbiesiorBiesioroff It was my mistake, I had play.api.Play imported instead of play.Play! sorry for the confusion

[biesior]

@nightograph, that's good news I was afraid that's something worse :) be careful, every class starting with play.api is for using in Scala controllers.

[nightograph]

@MarcusbiesiorBiesioroff ohh!!! that's great tip Marcus. thanks so much! I was so confused why the framework would have 2 Play objects. Better naming would had been nicer Play.scala and play.java for example

[Nasir]

I modified the answer, so hopefully, it will not cause confusion in the future :) - Kudos to nico_ekito who clarified it first

[cdmckay]

Why can't you use current?

[Jeroen Kransen]

Play.current.configuration.getString("your.key") seems to be the way in Play 2.2.2

[vdshb]

Yep! This variant is way better than others. It works in filters too (before Global object initialized).

[redent84]

Beware that this will load the default configuration file, but if you loaded other files afterwards (for example, application.dev.conf) in Global, it won't be taken into account. Found out the hard way :(

[gabby]

i was looking for that +1

[Ihor Patychenko]

for exactly what I was looking for +1

[Lasitha Yapa]

Play.application() is now deprecated. So update to the answer would be nice.

[Nasir]

@LasithaYapa I would check i.am.michiel's reply below and see if it helps. I haven't used Play in years now.

[Cid]

If you are using latest version this may not work. Check Saeed's response

[pcejrowski]

This approach is deprecated, use dependency injection instead.

[Karlth]

Still works in 2.5. I have no idea why a single config read suddenly needs dependency injection. :/

[Spenhouet]

Since Play 2.6.0 Configuration is deprecated and you need to inject com.typesafe.config.Config instead.

[Spenhouet]

Since 2.6.0 com.typesafe.config.Config should be used via dependency injection.

[user3504158]

Starting from version 2.5 this approach is deprecated. Please use play.Application class which should be injected and then application.config().getString("your.property.here")