Extend HelloWorld Example With DI

In the previous example, we have developed our first Play Framework HelloWorld Web Application.

For a clear separation between the Play Web Application with DI and without DI, I'll create a new project with the same content without changing the previous project:

1. Create a Play Framework SBT Project from your favorite IDE (I am using IntelliJ IDEA):

Project Name: play-scala-helloworld-di-app 

2. Copy the complete content of play-scala-helloworld-app into this project.
3. Create a HelloWorld Play Controller with DI:

HelloWorldDIController.scala:

package controllers 
import javax.inject._ 
import play.api.mvc._ 
@Singleton 
class HelloWorldDIController @Inject() extends Controller { 
  def helloWorld = Action { 
    Ok(views.html.helloWorld("Hello World With DI.")) 
  } 
} 

Note

We will use the same Play View Template for both HelloWorld Controllers.

The following table describes the most important and frequently used Play Web Application annotations:

Annotation	Description
@Inject...