How to run Play Framework 2.x in debug mode in IntelliJ IDEA?

Question

I want to run Play Framework 2.x in debug mode in IntelliJ IDEA. I searched in the Internet and all results say that you have to use play console.

Is it possible to

Answer 1

You need to use Idea 12+ Ultimate Edition

• Install Play 2.0 Support, Scala and other required plugins in Idea
• In command line perform play idea to generate project
• Open created project in Idea (open, don't import)
• Go to: Menu > Run > Edit Configurations... > Add New Configuration... > choose Play 2 App
• In Menu > Run new buttons will appear Debug and Run, first will run app with enabled debbuger.

Answer 2

1. Open Intellij IDEA
2. Open project - browse your app directory Run - Edit Configuration
3. Add new configuration - Play2
4. Add http://localhost:9000 to url to open option
5. Add -Xms512M -Xmx1024M -Xss1M -XX:+CMSClassUnloadingEnabled -XX:MaxPermSize=256M to JVM option
6. Set Debug port to 9999
7. Set your debug point and debug your application. Cheers :)

FYI : All of the above fields might filled up already

Answer 3

Using activator :

1. From Terminal (Not intellij terminal), enter command : activator ui
2. Open your existing app
3. Choose "Code view & Open in IDE
4. In Browse Code, click setting icon
5. Choose Open Project in Intellij IDEA

6. Generate

7. Open Intellij IDEA

8. Open project - browse your app directory
9. Run - Edit Configuration
10. Add new configuration - Remote
11. Add name Setting transport : socket, debugger mode : attach, Host : localhost, port : 9999 module clashpath : your app
12. Tools - Open Terminal
13. activator -jvm-debug 9999 run
14. Run debug
15. Open browser localhost:9000

Answer 4

Preparation: Do not use the project creation by activator ui or similar. Just open the project in IntelliJ.

1. activator -jvm-debug 9999 ~run. The ~ before run enables automatic reloading of generated HTML pages
2. In IntelliJ:
   1. Run > Edit Configurations...
   2. Select Defaults/Remote
   3. Click on the green + at the upper left corner
   4. Give the name "Play 2"
   5. Ensure that Transport:Socket and Debugger mode:Attach are selected
   6. Type in 9999 as port
   7. Press "OK"
3. Run > Debug Play 2 (second entry in the list)

Pro hint: Check out the play-auto-refresh plugin to have Chrome automatically reloading on a change.

(based on @ARM's answer)