The code is from this repository: https://github.com/akka/akka-samples/tree/2.5/akka-sample-distributed-data-scala
➜ akka-sample-distributed-data-scala git:(2.5) ✗ sbt run
[info] Loading project definition from /Volumes/Macintosh HD/github/akka-samples/akka-sample-distributed-data-scala/project
[info] Set current project to akka-sample-distributed-data-scala (in build file:/Volumes/Macintosh%20HD/github/akka-samples/akka-sample-distributed-data-scala/)
[info] Updating {file:/Volumes/Macintosh%20HD/github/akka-samples/akka-sample-distributed-data-scala/}akka-sample-distributed-data-scala...
[info] Resolving jline#jline;2.14.5 ...
[info] Done updating.
[info] Compiling 1 Scala source to /Volumes/Macintosh HD/github/akka-samples/akka-sample-distributed-data-scala/target/scala-2.12/classes...java.lang.RuntimeException: No main class detected.
at scala.sys.package$.error(package.scala:27)
[trace] Stack trace suppressed: run last compile:run for the full output.
[error] (compile:run) No main class detected.
[error] Total time: 6 s, completed 2018-5-27 10:07:14
It seems I run in a wrong way, how can I run it?
So I think it's an example that you need to add to your project. So you can't run it because as console tell you "No main class detected". This example contains code and you can go through it and learn.
So if you want to run it, you need to create an object with the main method and inside main, you can use everything from another part of the project.
Here you can see that everything is okay with code because compilation finished correctly.
Here you can find more information about this library:
https://doc.akka.io/docs/akka/2.5/distributed-data.html?language=scala
Related
I am attempting to create the PlayFramework Scala seed project.
So far I've used sbt new playframework/play-scala-seed.g8 command and it has created the necessary files within my root directory movie-app.
From this point, PlayFramework says to run sbt run, so I tried that, but I get the following error:
[info] Updated file *omitting personal directories*/Movie-App/project/build.properties: set sbt.version to 1.4.7
[info] welcome to sbt 1.4.7 (Ubuntu Java 11.0.10)
[info] loading project definition from *omitting personal directories*/Movie-App/project
[info] set current project to movie-app (in build file:*omitting personal directories*/Movie-App/)
[error] java.lang.RuntimeException: No main class detected.
[error] at scala.sys.package$.error(package.scala:30)
[error] stack trace is suppressed; run last Compile / bgRun for the full output
[error] (Compile / bgRun) No main class detected.
[error] Total time: 0 s, completed Jul 2, 2021, 11:27:33 PM
I haven't found anything helpful online yet.
Do I need to set the current project to "movie-app" like the error says? If so what do I need to write in the build.properties file?
If not, can anyone please explain the issue?
Thanks
$> sbt new playframework/play-scala-seed.g8
This template generates a Play Scala project.
Give it a name when asked. Skip rest by pressing enter.
name [play-scala-seed]: movie-app
$> cd movie-app
$> sbt run
I get an error when I want to run any example through mvn verify
[ERROR] ********************************************************************************************
[ERROR] Could not locate suitable Artemis.home on either D:\Documents\IdeaProjects\activemq-artemis\examples\features\standard\security\..\..\..\.. or D:\Documents\IdeaProjects\activemq-artemis\examples\features\standard\security\..
\..\..\..\artemis-distribution\target\apache-artemis-2.18.0-SNAPSHOT-bin\apache-artemis-2.18.0-SNAPSHOT
[ERROR] Use the binary distribution or build the distribution before running the examples
[ERROR] ********************************************************************************************
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 4.087 s
[INFO] Finished at: 2021-02-26T22:03:39+03:00
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal org.apache.activemq:artemis-maven-plugin:2.18.0-SNAPSHOT:create (create) on project security: Couldn't find artemis.home -> [Help 1]
I tried to specify the path to the directory with artemis at startup, but it does not help mvn verify -Dartemis.home="D:\Documents\apache-artemis-2.17.0"
How to fix this error?
It appears you're running the example directly from the project source since it reports 2.18.0-SNAPSHOT. If that's the case then you should do what the ERROR message indicates:
Use the binary distribution or build the distribution before running the examples
You can get a snapshot binary distribution here or you can build the distribution from the source using mvn install -Prelease -DskipTests.
If you must point the example at a different home directory you can do so using the activemq.basedir system property, e.g.:
mvn verify -Dactivemq.basedir="D:\Documents\apache-artemis-2.17.0"
Or you can change the activemq.basedir property defined in the example's pom.xml.
I am trying to learn Scala by implementing a simple API in Play framework. I am creating an app by command
activator new app play-scala
Then in app folder I'm doing activator run then it starts downloading tons of data from internet. I tried offline:=true in build.sbt and using the offline version activator instead of minimal one but with no success.
[info] Loading project definition from /home/amit/Codes/scala/app/project
[info] Updating {file:/home/amit/Codes/scala/app/project/}app-build...
[info] Resolving org.fusesource.jansi#jansi;1.4 ...
[info] Done updating.
[info] Set current project to app (in build file:/home/amit/Codes/scala/app/)
[info] Updating {file:/home/amit/Codes/scala/app/}root...
[info] Resolving jline#jline;2.12.1 ...
[info] downloading https://repo1.maven.org/maven2/com/typesafe/play/play-omnidoc_2.11/2.5.3/play-omnidoc_2.11-2.5.3.jar ...
[info] downloading http://repo.typesafe.com/typesafe/ivy-releases/com.typesafe.sbtrc/client-2-11/0.3.1/jars/client-2-11.jar ...
[info] [SUCCESSFUL ] com.typesafe.sbtrc#client-2-11;0.3.1!client-2-11.jar (102499ms)
[info] downloading https://repo1.maven.org/maven2/org/scala-lang/scala-reflect/2.11.5/scala-reflect-2.11.5.jar ...
[info] [SUCCESSFUL ] org.scala-lang#scala-reflect;2.11.5!scala-reflect.jar (136599ms)
[info] downloading http://repo.typesafe.com/typesafe/ivy-releases/org.scala-sbt/serialization_2.11/0.1.0/jars/serialization_2.11.jar ...
[info] [SUCCESSFUL ] org.scala-sbt#serialization_2.11;0.1.0!serialization_2.11.jar (12655ms)
[info] downloading http://repo.typesafe.com/typesafe/ivy-releases/org.scala-sbt/io_2.11/0.13.8-M3/jars/io_2.11.jar ...
I have a very slow connection and I am stuck with it. I don't know something that easy in python-flask can be so difficult in scala-play or am I missing something?
By issuing activator new app play-scala activator only creates a copy of template (usually located at ~/.activator//templates). Of course template itself has to be downloaded first but it is normally tiny.
Effect what you are seeing is that when you run activator run the SBT first time resolves dependencies of your application created according to template. Two situations can happen:
you have already a lot of dependencies in your ~/.ivy2 directory because e.g. you have created project according to the template before or project with similar dependencies via SBT (not strictly with activator). Then the dependencies will be resolved and not downloaded.
you have no dependencies at all in ~/.ivy2 or your template uses such different ones that they have to be downloaded.
Your milage may vary, but important point is that your dependencies are related to your template not activator itself. Another important thing to note is that they have to be definitely downloaded at least once to be used (this is strongly dependent from state of your ~/.ivy2 directory).
I guess that you are trying activator for the first time, or at least play-scala template, thus you have to wait and definitely use better internet connection :)
While following an example to deploy an application in Spark, I keep getting the error below while "compile" in sbt.
[info] Updating {file:/home/sankalp/Desktop/spark/SVMexample/}svmexample...
[info] Resolving com.sun.jersey.jersey-test-framework#jersey-test-framework-grizzl[info] Resolving jline#jline;2.12.1 ...
[info] Done updating.
[info] Compiling 1 Scala source to /home/sankalp/Desktop/spark/SVMexample/target/scala-2.11/classes...
[error] error while loading <root>, Error accessing /home/sankalp/.ivy2/cache/org.apache.spark/spark-core_2.11/jars/spark-core_2.11-1.4.0.jar
[trace] Stack trace suppressed: run last compile:compileIncremental for the full output.
[error] (compile:compileIncremental) scala.reflect.internal.MissingRequirementError: object java.lang.Object in compiler mirror not found.
[error] Total time: 21 s, completed Aug 16, 2015 2:36:53 AM
Can anyone help?
Thanks,
I am no expert, but in my case it helped editing:
project/Versions.scala -> val Spark = "1.4.0" -> "1.4.1".
Although it is actually a mystery to me why it did help :).
EDIT:
On the second thought i've noticed by accident, that the file spark-core_2.11-1.4.0.jar was broken (each time it was downloaded by sbt).
It also helped to replacing .jar with valid one from:
http://mvnrepository.com/artifact/org.apache.spark/spark-core_2.11/1.4.0
I suppose it is somehow connected with spark-cassandra-connector build system or repo from which file is downloaded.
Maybe we should file an issue.
EDIT2:
i found out, that broken .jar comes from (at least in my case):
https://jcenter.bintray.com/org/apache/spark/spark-core_2.11/1.4.0/spark-core_2.11-1.4.0.jar
you can see its origin in: .ivy2/cache/org.apache.spark/spark-core_2.11/ivydata-1.4.0.properties
i did not manage to find out why it comes from jcenter (https://bintray.com/bintray/jcenter). maybe it is somehow connected with adding bintray repo to my linux mint or new version of sbt or datastax uses bintray. i will probably investigate later.
The previous suggestions seemed very specific to a particular use case. My solution is inefficient, brute force, but was effective:
Reinstall IntelliJ completely
Follow steps in this post,
I use gwt-maven-plugin 2.6.0, when I run mvn gwt:run-codeserver it compiled successfully:
[INFO] binding: user.agent=safari
[INFO] Compiling module com.example.myModule
[INFO] Validating units:
[INFO] Ignored 3 units with compilation errors in first pass.
[INFO] Compile with -strict or with -logLevel set to TRACE or DEBUG to see all errors.
[INFO] ...
[INFO] Compiling 1 permutation
[INFO] Compiling permutation 0...
[INFO] Source Maps Enabled
[INFO] Compile of permutations succeeded
[INFO] Linking into C:\Users\admin\AppData\Local\Temp\gwt-codeserver-5664784549647002986.tmp\com.example.myModule\compile-4\war\myModule;
Writing extras to C:\Users\admin\AppData\Local\Temp\gwt-codeserver-5664784549647002986.tmp\com.example.myModule\compile-4\extras\myModule
[INFO] Link succeeded
[INFO] Compilation succeeded -- 3.401s
[INFO] Compile completed in 3496 ms
Then I started the dev server using mvn install gwt:run, made changes on my source file and click the Dev Mode On bookmark. After compiling the changes cannot reflect to UI: the UI always show old values.
Any ideas on this problem?
There's a bug in gwt-maven-plugin up to (including) 2.6.0; you have to run mvn process-classes gwt:run-codeserver instead of just mvn gwt:run-codeserver. This is fixed in 2.6.1.
Also, if you change anything in src/main/resources, you'll have to run mvn process-resources to make your changes available to Super Dev Mode (this is because you might use resource filtering, so Super Dev Mode doesn't directly look at src/main/resources).
Similarly, if you use plugins that generate resources or Java sources, you'll have to run them manually (e.g. mvn generate-sources or mvn generate-resources; or just use the same mvn process-resources as above, which will do everything at once). This will be necessary for example if you use gwt:generateAsync and change your GWT-RPC interface (note that you'll also have to redeploy your server-side code).
Note: I just updated my answer in the linked post for GWT 2.6.0, and added a note about GWT-RPC, and the gwt-maven-plugin bug.