Why Play Framework uses old Ebean version in the new project templates?

问题

I was bashing my head to the wall (almost literally) trying to figure out why I was having this NullPointException problem for the past 17 days (now you believe, don't you ?).

So, reading and reading through Play's Documentation I have noticed something ( that I don't know how I haven't noticed before! ).

Configuring Ebean Play comes with the Ebean ORM. To enable it, add the Play Ebean plugin to your SBT plugins in project/plugins.sbt:

addSbtPlugin("com.typesafe.sbt" % "sbt-play-ebean" % "3.0.0")

Also, reading some posts at Play's forum, I have noticed that version 2.5.6 was released, and I was using version 2.5.4, in any case I upgrade it both and it worked, it solved my NullPointerException problem.

However, I have created a new project via Play's template:

activator new

Fetching the latest list of templates...

Browse the list of templates: http://lightbend.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
Enter a name for your application (just press enter for 'play-java')
> a-new-project
OK, application "a-new-project" is being created using the "play-java" template.

To run "a-new-project" from the command line, "cd a-new-project" then:
/tmp/000/a-new-project/activator run

To run the test for "a-new-project" from the command line, "cd a-new-project" then:
/tmp/000/a-new-project/activator test

To run the Activator UI for "a-new-project" from the command line, "cd a-new-project" then:
/tmp/000/a-new-project/activator ui

Then checking project/plugins.sbt file:

// Play Ebean support, to enable, uncomment this line, and enable in your build.sbt using
// enablePlugins(PlayEbean).
// addSbtPlugin("com.typesafe.sbt" % "sbt-play-ebean" % "1.0.0")

Which leads to my question: if you're starting a new project, via play's project template, why would you start with the oldest version of a plugin ? It would be better to start with the latest version of these plugins ?

You can see my changes on my repository here.

回答1:

Not a big deal. It is just that the template got outdated. The play-java template is defined here:

https://github.com/playframework/playframework/tree/master/templates/play-java

And, you can see that the template is adding play-ebean plugin here:

https://github.com/playframework/playframework/blob/master/templates/play-java/project/plugins.sbt#L21

Unfortunately, the EBEAN_VERSION variable was not updated, as you can see here:

https://github.com/playframework/playframework/blob/master/templates/build.sbt#L62

If you want, you can submit a (very small and specific) pull request to fix this.

Edit:

This pull request updates templates plugins: https://github.com/playframework/playframework/pull/6515

来源：https://stackoverflow.com/questions/39263538/why-play-framework-uses-old-ebean-version-in-the-new-project-templates

标签

java

playframework

playframework-2.0

sbt

ebean