Questions tagged [scala]
Scala is a general-purpose programming language principally targeting the Java Virtual Machine. Designed to express common programming patterns in a concise, elegant, and type-safe way, it fuses both imperative and functional programming styles. Its key features are: an advanced static type system with type inference; function types; pattern-matching; implicit parameters and conversions; operator overloading; full interoperability with Java; concurrency
scala
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questions with no upvoted or accepted answers
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Materialize the Value for a Type that has One Inhabitant
Thanks to @MilesSabin's answer I can write a type level Fibonacci sequence:
sealed trait Digit
case object Zero extends Digit
case object One extends Digit
sealed trait Dense { type N <: Dense }
...
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Problem with compilation for maven project
I have two maven projects - a library and a small program. They are in different folders and use different pom.xml and the library's jar files are included in the small program's pom.xml using the ...
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Integrating Play Framework 2.6 with gRPC and Netty
At the time I write this post, Play Framework is at v2.6.0-M4. The v2.5 version of the framework had difficulties to work with gRPC because of Netty conflicts (see this stackoverflow answer).
I'm ...
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Scaffolding for Play Framework 2
Is there scaffolding generator utility for Play Framework 2 for Scala like Ruby on Rails has? I found some topics about this but didn't figure out which one was most popular or even if there was the ...
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Dynamically creating Akka Stream Flows at Runtime
I'm currently trying to dynamically create Akka Stream graph definitions at runtime. The idea being that users will be able to define flows interactively and attach them to existing/running ...
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How to override guice modules in Playframework unit tests using ScalaTest
I want to write functional test for my controller in PlayFramework. To do that I want to mock implementation of some classes.
I found nice example of how to do that using spec2 here: http://www....
- 1,973
13
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answer
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Best strategy to upload files with unknown size to S3
I have a server-side application that runs through a large number of image URLs and uploads the images from these URLs to S3.
The files are served over HTTP. I download them using InputStream I get ...
- 1,412
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How to choose bucket length in Spark's Bucketed Random Projection?
How should I optimally choose bucket length in Spark's LSH algorithm Bucketed Random Projection?
It is this parameter set with .setBucketLength(), e.g. from the Spark documentation:
val brp = new ...
- 143
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akka http throws EntityStreamException: Entity stream truncation
I'm writing a client for a rest API using the akka http library. The library seems very powerful, but it works very unstable for me. Quite often (not always) it throws the following exception when I ...
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How to get probabilities corresponding to the class from Spark ML random forest
I've been using org.apache.spark.ml.Pipeline for machine learning tasks. It is particularly important to know the actual probabilities instead of just a predicted label , and I am having difficulties ...
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Calling scala code in pyspark for XSLT transformations
This might be a long shot, but figured it couldn't hurt to ask. I'm attempting to use Elsevier's open-sourced spark-xml-utils package in pyspark to transform some XML records with XSLT.
I've had a ...
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How can I use http request headers for content negotiation in a Mashaller?
My app supports protobuf and JSON serialzation. For JSON serialization I use com.trueaccord.scalapb.json.JsonFormat, my dtos are generated from proto definitions.
The com.trueaccord serializer wraps ...
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Apache Spark and Domain Driven Design
I've got somewhat of an abstract question. I've been using Apache Spark (also Streaming and SQL) with Scala quite a lot lately. Most of my Spark jobs basically move RDDs/Dataframes from one class to ...
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Scaladoc diagrams
Is it possible to generate diagrams with Scaladoc and SBT?
I tried to add this line in my build.sbt:
scalacOptions in (Compile,doc) := Seq("-diagrams", "-diagrams-debug")
But I receive:
Diagram ...
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PowerMockito throwing ClassNotPreparedException even with @PrepareForTest using Scala Test
I have the following test...
import org.scalatest.junit.JUnitRunner
...
@PowerMockRunnerDelegate(classOf[JUnitRunner])
@PrepareForTest(Array(classOf[AuditLog]))
class ConnectorAPITest extends path....
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