What is controller in play framework?

What is controller in play framework?

Controller overview A Controller is a Java class, hosted by the controllers package, and subclassing play. mvc. Controller .

What is Scala route?

The routes file syntax conf/routes is the configuration file used by the router. This file lists all of the routes needed by the application. Each route consists of an HTTP method and URI pattern, both associated with a call to an Action generator. You can also add comments to the route file, with the # character.

What is Scala action?

Spark Action Examples in Scala. When using Spark API “action” functions, a result is produced back to the Spark Driver. Computing this result will trigger any of the RDDs, DataFrames or DataSets needed in order to produce the result.

What is action in play framework?

What is an Action? Most of the requests received by a Play application are handled by an action. An action is basically a Java method that processes the request parameters, and produces a result to be sent to the client. public Result index(Http.

What is controller in Scala?

A Controller is a Scala singleton object, hosted by the controllers package, and subclassing play. mvc. In Scala you can declare as many controllers you want in the same file.

What is Play and Akka?

Akka is a toolkit and runtime for building highly concurrent, distributed, and resilient message-driven applications on the JVM. On the other hand, Play is detailed as “The High Velocity Web Framework For Java and Scala”. Play Framework makes it easy to build web applications with Java & Scala.

What is Akka directive?

A “Directive” is a small building block used for creating arbitrarily complex route structures. Akka HTTP already pre-defines a large number of directives and you can easily construct your own: Basics.

What is DSL in Akka?

Akka HTTP provides a flexible routing DSL for elegantly defining RESTful web services. It picks up where the low-level API leaves off and offers much of the higher-level functionality of typical web servers or frameworks, like deconstruction of URIs, content negotiation or static content serving.

What does collect () do in spark?

Spark collect() and collectAsList() are action operation that is used to retrieve all the elements of the RDD/DataFrame/Dataset (from all nodes) to the driver node. We should use the collect() on smaller dataset usually after filter(), group(), count() e.t.c. Retrieving on larger dataset results in out of memory.

Is Play framework asynchronous?

Internally, Play Framework is asynchronous from the bottom up. Play handles every request in an asynchronous, non-blocking way. The default configuration is tuned for asynchronous controllers.

What is case class in Scala with example?

A Scala Case Class is like a regular class, except it is good for modeling immutable data. It also serves useful in pattern matching, such a class has a default apply() method which handles object construction. A scala case class also has all vals, which means they are immutable. Let’s Revise Scala Syntax with example.