Questions tagged [playframework]
Play Framework is a modern open-source web framework for Java and Scala.
17,283
questions
345
votes
7
answers
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Understanding implicit in Scala
I was making my way through the Scala playframework tutorial and I came across this snippet of code which had me puzzled:
def newTask = Action { implicit request =>
taskForm.bindFromRequest.fold(
...
- 3,991
221
votes
24
answers
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views
How do I change the default port (9000) that Play uses when I execute the "run" command?
How can I change the default port used by the play framework in development mode when issueing the "run" command on the play console.
This is for playframework 2.0 beta.
Using the http.port ...
- 10.9k
120
votes
18
answers
215k
views
Error: Argument is not a function, got undefined
Using AngularJS with Scala Play, I'm getting this error.
Error: Argument 'MainCtrl' is not a function, got undefined
I'm trying to create a table consisting of the days of the week.
Please take a ...
- 41.5k
117
votes
6
answers
69k
views
RESTful on Play! framework
We are planning a project primarily serving content to mobile apps, but need to have a website.
My question is whether is makes sense to use Jersey or Restlet to develop REST APIs for our mobile apps,...
- 1,179
93
votes
1
answer
17k
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Advice deploying war files vs executable jar with embedded container
There seems to be a current trend in java space to move away from deploying java web applications to a java servlet container (or application server) in the form of a war file (or ear file) and ...
- 10.4k
90
votes
10
answers
79k
views
Steps needed to use MySQL database with Play framework 2.0
I'm new to Play framework. I'm trying to configure MySQL database as a datasource to be used with Play Ebeans.
Could you some one please explain the steps that are needed to configure MySQL with ...
- 32.9k
85
votes
3
answers
59k
views
Creating a composite Unique constraints on multiple columns
This is my model:
class User {...}
class Book {
User author;
int number;
}
Every book number starts at 1 per author and increments upwards. So we'll have Books 1,2,3 by John Grisham, Book 1..5 ...
- 226k
75
votes
14
answers
15k
views
Play! framework uses a <lot> of statics
Waaah, the Play! framework has so many static methods. Where I go to school, we were told never ever to use any statics, yet Play! uses it like there's no tomorrow. Is that somehow okay? If so, why?
...
- 1,056
75
votes
6
answers
60k
views
How to handle optional query parameters in Play framework
Lets say I have an already functioning Play 2.0 framework based application in Scala that serves a URL such as:
http://localhost:9000/birthdays
which responds with a listing of all known birthdays
...
- 1,396
73
votes
1
answer
2k
views
Optimizing JS from WebJars using sbt-rjs in a Play 2.3.x app
Is it possible to have a Play 2.3 app concat/optimize JS (using sbt-rjs) that's included in my app via WebJars? To give a concrete example: I'm trying to create a core.js module which contains all my ...
- 731
71
votes
2
answers
36k
views
How to find out which Play version I'm using?
Kinda silly question, but I used Activator to get started with the play framework, and now need to see what version I'm using. 2.3 came out with support for docker, but when I put
dockerExposedPorts ...
- 8,005
70
votes
1
answer
3k
views
What are the problems with an ADT encoding that associates types with data constructors? (Such as Scala.)
In Scala, algebraic data types are encoded as sealed one-level type hierarchies. Example:
-- Haskell
data Positioning a = Append
| AppendIf (a -> Bool)
| ...
- 91.5k
68
votes
9
answers
25k
views
SBT compilation for play framework 2.x disabled by default
I created a new Play Framework project using the activator, activator new my-project-name and then I selected the play-java template and the project is created with no errors.
Then I import the ...
- 7,900
65
votes
5
answers
18k
views
Experiences on free and low-cost hosting for play framework applications? [closed]
I'd like to know your experience finding a host for play applications on free or low-cost servers
So far now I found the following options:
Playapps (discontinued)
A cloud hosting solution by ...
- 61.8k
62
votes
13
answers
56k
views
Accessing the application.conf properties from java class with Play! 2.0
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 ...
- 160k
62
votes
9
answers
10k
views
any experience with "Play" java web development framework? [closed]
I've just stumbled upon the following new java web framework: Play
http://www.playframework.org/
http://www.playframework.org/documentation/1.0/home
with such a stunning list of features, I'm ...
- 61.8k
61
votes
1
answer
18k
views
How is Akka used in Play?
Play's home page says:
Built on Akka, Play provides predictable and minimal resource consumption (CPU, memory, threads) for highly-scalable applications.
I'd like to know exactly how and where ...
- 7,721
61
votes
5
answers
4k
views
Jenkins + Play 1.2.4 : problems with cobertura lock files / report
We have a Play 1.2.4 application and we got Jenkins (on Ubuntu) for the application. We're having problems with Cobertura.
After running the tests (succesfully), every now and then, we get the ...
- 11.6k
60
votes
3
answers
21k
views
Play framework hangs on startup at: "Loading project definition from"
I am just getting started with Play Framework. I have downloaded and installed play and created a sample java application. When I try to start the play console in the application directory it hangs at ...
- 3,098
59
votes
9
answers
45k
views
Declare variable in a Play2 scala template
How do you declare and initialize a variable to be used locally in a Play2 Scala template?
I have this:
@var title : String = "Home"
declared at the top of the template, but it gives me this error:
...
- 8,332
59
votes
3
answers
36k
views
What is the difference between 'CompletionStage' and 'CompletableFuture'
I have seen an example in each of them, but I need to know exactly what is the difference in deep because I think I can use both of them to get the same result, So I want to know then I can choose the ...
- 2,200
57
votes
5
answers
14k
views
How can colored terminal output be disabled for sbt/play?
I would like to disable the color escape codes logged from sbt/play. Is this possible? And if it is, is there a way to do it without making changes to the config - i.e. via a command line switch or ...
- 2,070
54
votes
2
answers
23k
views
NodeJS vs Play Framework for large project
I am really torn between two different stacks with which to build a large application. One the one hand there is this option:
Node.js
express
coffee script
coffeekup
mongoose/mongodb
or
...
- 14.3k
53
votes
5
answers
4k
views
-Ywarn-unused-import triggering on play routes file
I want to be able to use -Xfatal-warnings and -Ywarn-unused-import, the problem is that the compiler is triggering an error on the file which contains the play routes for my application:
[error] /...
- 15.7k
52
votes
6
answers
14k
views
What are the major differences between Play Framework 1.0 and 2.0?
With the recent release of Play Framework 2.0, I would like to know if anyone could summarize ,from a high level standpoint, the major differences between Play Framework 1 & 2.
I already compiled ...
- 50.9k
51
votes
1
answer
11k
views
How to declare a variable named 'type' in Play/Scala?
I want to declare a variable with name 'type' in a Play/Scala application, since my data has this field name and I'm using JSON transforms. It just makes more sense.
Fortunately I could just rename ...
- 1,220
50
votes
1
answer
35k
views
Web Frameworks: How is Play different from Spring MVC? [closed]
The Play Framework offers the following quick overview, but with the exception of the Groovy template engine (which you can get in Spring MVC if you want), Spring seems to offer all the same features ...
- 517
49
votes
2
answers
19k
views
Play Framework 2.1 - Cannot find an implicit ExecutionContext
I am calling a webservice like this:
WS
.url(url)
.get
.map { response => // error occurs on this line
response.status match {
case 200 => Right(response.json)
case status ...
- 11.2k
49
votes
6
answers
26k
views
Where do I put startup code in Play Framework?
I want to run some code on startup to pre-cache some stuff, and would also like to start a Timer to re-cache some things outside the critical path of a web request. Is this possible with Play ...
- 35.6k
48
votes
4
answers
16k
views
Noise free JSON format for sealed traits with Play 2.2 library
I need to get a simple JSON serialization solution with minimum ceremony. So I was quite happy finding this forthcoming Play 2.2 library. This works perfectly with plain case classes, e.g.
import ...
- 67.1k
48
votes
6
answers
9k
views
Why does java wait so long to run the garbage collector?
I am building a Java web app, using the Play! Framework. I'm hosting it on playapps.net. I have been puzzling for a while over the provided graphs of memory consumption. Here is a sample:
The ...
- 7,916
47
votes
4
answers
52k
views
how to remove key value from map in scala
Map(data -> "sumi", rel -> 2, privacy -> 0, status -> 1,name->"govind singh")
how to remove data from this map , if privacy is 0.
Map(rel -> 2, privacy -> 0, status -> 1,name-...
- 15.4k
46
votes
5
answers
25k
views
Adding Play JSON Library to sbt
How can I add the Play JSON library (play.api.libs.json) to my sbt project?
When I added the following to my plugins.sbt file:
addSbtPlugin("play" % "sbt-plugin" % "2.1.0")
I faced this error:
[...
- 41.5k
46
votes
5
answers
54k
views
GSON JsonObject "Unsupported Operation Exception: null" getAsString
Running a Play! app with Scala. I'm doing a request where the response is expected to be a JSON string. When checking the debugger, the JsonElement returns OK with all information as expected. However,...
- 13k
45
votes
3
answers
22k
views
Play 2.4: Form: could not find implicit value for parameter messages: play.api.i18n.Messages
I am new to Play framework and tried to mimic the helloworld sample in my local machine but I encountered an error:
routes:
# Home page
GET / controllers.Application.index
...
- 573
44
votes
2
answers
41k
views
ProcessBuilder gives a "No such file or directory" while Runtime().exec() works fine
I have an application, running on the Playframework, which needs to encode some video files. I used
Process pr = Runtime.getRuntime().exec(execCode)
for this (and it works perfectly), but as I need ...
- 4,462
42
votes
2
answers
25k
views
What is a Boxed Error in Scala?
When I run my application, the browser shows
[ExecutionException: Boxed Error]
It doesn't say anything about the line number, etc.
In the console, I have the following
! @6elaah0c8 - Internal ...
- 1,191
42
votes
3
answers
23k
views
Play Framework - add a field to JSON object
I have a problem with adding a field to Json object in Play Framework using Scala:
I have a case class containing data. For example:
case class ClassA(a:Int,b:Int)
and I am able to create a Json ...
- 1,035
42
votes
5
answers
44k
views
Separate back-end and front-end apps on same domain?
We are building a fully RESTful back-end with the Play Framework. We are also building a separate web front-end with a different technology stack that will call the RESTful API.
How do we deploy both ...
- 2,509
42
votes
7
answers
21k
views
Securing REST API on Play framework and OAuth2
I am developing an application with Play 2.0 and Scala that exposes some REST API. These APIs will be used by different applications, web, mobile or desktop, so the OAuth protocol (OAuth2) seems the ...
- 1,642
42
votes
3
answers
7k
views
Discovery of Akka actors in cluster
I’ve been trying to wrap my head around the concepts of Akka and actor-based systems recently. While I have a pretty good understanding of the Akka fundamentals by now I’m still struggling with a few ...
- 3,781
40
votes
7
answers
25k
views
Does Playframework 2.0.x support <else if> in templates
I wonder if play 2.0.3 and higher supports else if in views? I only read that one have to code that way: if {...}else{if{...}else{...}} cannot believe that.
- 755
39
votes
2
answers
19k
views
Choosing a Scala web framework [closed]
I am about to start a project for a web application that should run on a Tomcat server. I have decided to go for Scala - the other alternative where I work being Groovy - essentially for type safety. ...
- 20.4k
38
votes
7
answers
36k
views
Debug Playframework in Eclipse
I just moved from Netbeans to Eclipse. In Netbeans, I can debug Playframework applications out of the box. However, in Eclipse, it seems hard to configure this in order to debug a web app (a ...
- 1,151
38
votes
6
answers
60k
views
“Convert” Option[x] to x
I working with play for Scala (2.1) and I need to convert an Option[Long] value to Long.
I know how to do the opposite, I mean:
def toOption[Long](value: Long): Option[Long] = if (value == null) None ...
- 553
38
votes
5
answers
21k
views
Spray, Akka-http and Play, Which is the best bet for a new HTTP/REST project
I'm going to develop new HTTP/REST services using Scala and Akka Actors.
I have experience working with Play, but I don't really need a complete web Framework.
From what I read, I think Spray is a ...
- 854
37
votes
1
answer
18k
views
Play Framework @routes.Assets.at Compilation Error
I'm using Play 2.4.0 and I've been trying to follow the tutorial from the main page: https://playframework.com/
which is for Play 2.3 and after solving a couple of issues regarding changes in the ...
- 1,591
35
votes
3
answers
10k
views
Play's execution contexts vs scala global
How does the execution context from
import scala.concurrent.ExecutionContext.Implicits.global
differ from Play's execution contexts:
import play.core.Execution.Implicits.{internalContext, ...
- 11.3k
34
votes
6
answers
14k
views
How to detect application mode in Play 2.x
From within a Play 2.1 application, how would I programmatically determine which mode the application is running in (i.e., Development vs. Production)?
For example, it would be useful to be able to ...
- 6,043
34
votes
4
answers
8k
views
Frameworks comparation: Lift, Play and Wicket
What are the advantages and disadvantages of frameworks Lift, Play and Wicket? What characteristics are best or only supported by each?
Thanks
- 3,718