First application using Play Framework

First application using Play Framework:

Before going to implement the First play application, we need to know some thing about activator and it's commands:

Activator:  

• Typesafe Activator is a browser based or command line tool that helps developers get started with the Typesafe Reactive Platform.
• Activator includes the sbt build tool, a quick-start GUI, and a catalog of template applications. 
• Activator allows us to select a template that our new application should be based off.  The names of the templates are play-scala for Scala based Play applications and play-java for Java based Play applications.

The following are the important commands of activator:

Command name	Description
activator	To run the Console
activator ui	Start the Activator UI
activator new [name] [template-id]	Create a new project with [name] using template [template-id]
activator list-templates	Print all available template names
activator help	Print this message

Creating the new application:
To create a new applications we need to use the activator new command.

D:\Play\My_Practise>activator new HelloWorld
Fetching the latest list of templates...

Browse the list of templates: http://typesafe.com/activator/templates
Choose from these featured templates or enter a template name:
1) minimal-akka-java-seed
2) minimal-akka-scala-seed
3) minimal-java
4) minimal-scala
5) play-java
6) play-scala

(hit tab to see a list of all templates)
> 5
OK, application "HelloWorld" is being created using the "play-java" template.

To run "HelloWorld" from the command line, "cd HelloWorld" then:
D:\Play\My_Practise\HelloWorld/activator run

To run the test for "HelloWorld" from the command line, "cd HelloWorld" then:
D:\Play\My_Practise\HelloWorld/activator test

To run the Activator UI for "HelloWorld" from the command line, "cd HelloWorld" then:

D:\Play\My_Practise\HelloWorld/activator ui

Project Structure:



Compiling the Project:
By using activator compile command, we can compile our application without running the server.

D:\Play\My_Practise\HelloWorld>activator compile
[info] Loading project definition from D:\Play\My_Practise\HelloWorld\project
[info] Updating {file:/D:/Play/My_Practise/HelloWorld/project/}helloworld-build...
[info] Resolving org.fusesource.jansi#jansi;1.4 ...
[info] Done updating.
[info] Set current project to HelloWorld (in build file:/D:/Play/My_Practise/HelloWorld/)
[info] Updating {file:/D:/Play/My_Practise/HelloWorld/}root...
[info] Resolving jline#jline;2.12.1 ...
[info] Done updating.
[info] Compiling 6 Scala sources and 2 Java sources to D:\Play\My_Practise\HelloWorld\target\scala-2.11\classes...
[success] Total time: 135 s, completed Jul 29, 2015 11:52:10 PM

Running the Project:
By using activator run command, we can run the application.

D:\Play\My_Practise\HelloWorld>activator run

[info] Loading project definition from D:\Play\My_Practise\HelloWorld\project

[info] Set current project to HelloWorld (in build file:/D:/Play/My_Practise/HelloWorld/)

--- (Running the application, auto-reloading is enabled) ---

[info] p.a.l.c.ActorSystemProvider - Starting application default Akka system: application

[info] p.c.s.NettyServer - Listening for HTTP on /0:0:0:0:0:0:0:0:9000

(Server started, use Ctrl+D to stop and go back to the console...)

Testing the Project:
By using activator test command, we can test the application.

D:\Play\My_Practise\HelloWorld>activator test
[info] Loading project definition from D:\Play\My_Practise\HelloWorld\project
[info] Set current project to HelloWorld (in build file:/D:/Play/My_Practise/HelloWorld/)
Warning: node.js detection failed, sbt will use the Rhino based Trireme JavaScript engine instead to run JavaScript assets compilation, which in some cases may be orders of magnitude slower than using node.js.
[info] Compiling 2 Java sources to D:\Play\My_Practise\HelloWorld\target\scala-2.11\test-classes...
[info] D:\Play\My_Practise\HelloWorld\test\ApplicationTest.java: D:\Play\My_Practise\HelloWorld\test\ApplicationTest.java uses or overrides a deprecated API.
[info] D:\Play\My_Practise\HelloWorld\test\ApplicationTest.java: Recompile with -Xlint:deprecation for details.
[info] - application - Creating Pool for datasource 'default'
[info] - play.api.libs.concurrent.ActorSystemProvider - Starting application default Akka system: application
[info] - play.api.libs.concurrent.ActorSystemProvider - Shutdown application default Akka system: application
[info] - application - Shutting down connection pool.
[info] Passed: Total 3, Failed 0, Errors 0, Passed 3
[success] Total time: 18 s, completed Jul 30, 2015 12:00:49 AM

Debugging the Project:
By using following command, we can debug the application.
activator -jvm-debug <port> 

$ activator -jvm-debug 9999
When a JPDA port is available, the JVM will log this line during boot:
Listening for transport dt_socket at address: 9999

Happy Coding!