I am getting the
No such file or class on classpath: com
when executing the scala uber jar using the below command.
scala -classpath kafka-scala-1.0-SNAPSHOT.jar com.< name >.< abc >.KafkaAggregateConsumerApp
I am using scala 2.11.12
From the error it looks like you might have a space after the com in your command. Re-check that please.
Also, if you already have an uber jar you can run the jar directly using the java command.
java -cp kafka-scala-1.0-SNAPSHOT.jar com.foo.bar.KafkaAggregateConsumerApp
Related
I have my .jar built from scala classes and it has an external dependency with other.jar. Please suggest how should I run my jar files in terminal. The command I tried is
$scala my_scala.jar external.jar
It works same way as running java program. Try this
scala -classpath <your_scala_jar>:<external_jar> <package.MainClass>
I've created a simple app that generates PageView for later Spark tasks.
I've only one scala file taht use a simple MAP
When created a package with SBT I run my class with command:
java -cp .\target\scala-2.10\pageviewstream_2.10-1.0.0.jar "clickstream.PageViewGenerator"
but I receive this error:
Exception in thread "main" java.lang.NoClassDefFoundError: scala/collection/immutable/Map
What I am doing wrong?
Many thanks in advance
Roberto
To run it correctly you need to add Scala runtime library into your class path:
java -cp $SCALA_HOME/lib/scala-library.jar;.\target\scala-2.10\pageviewstream_2.10-1.0.0.jar "clickstream.PageViewGenerator"
But .. you can run your application also as:
scala -classpath .\target\scala-2.10\pageviewstream_2.10-1.0.0.jar "clickstream.PageViewGenerator"
when you have scala already in PATH
or use directly sbt as:
sbt "runMain clickstream.PageViewGenerator"
when clickstream.PageViewGenerator is you only application it is enough to run:
sbt run
or when you are in sbt interactive mode just type:
> runMain clickstream.PageViewGenerator
or when it is only application in your project it is enough to run:
> run
I have a Spark project which I can run from sbt console. However, when I try to run it from the command line, I get Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/spark/SparkContext. This is expected, because the Spark libs are listed as provided in the build.sbt.
How do I configure things so that I can run the JAR from the command line, without having to use sbt console?
To run Spark stand-alone you need to build a Spark assembly.
Run sbt/sbt assembly on the spark root dir. This will create: assembly/target/scala-2.10/spark-assembly-1.0.0-SNAPSHOT-hadoop1.0.4.jar
Then you build your job jar with dependencies (either with sbt assembly or maven-shade-plugin)
You can use the resulting binaries to run your spark job from the command line:
ADD_JARS=job-jar-with-dependencies.jar SPARK_LOCAL_IP=<IP> java -cp spark-assembly-1.0.0-SNAPSHOT-hadoop1.0.4.jar:job-jar-with-dependencies.jar com.example.jobs.SparkJob
Note: If you need other HDFS version, you need to follow additional steps before building the assembly. See About Hadoop Versions
Using sbt assembly plugin we can create a single jar. After doing that you can simply run it using java -jar command
For more details refer
I tried to run junit4 test case from command line using:
java -cp junit-4.8.1.jar;test\Dijkstra;test\Dijkstra\bin org.junit.runner.JUnitCore Data0PathTest00
but I got the following error:
java.lang.NoClassDefFoundError: graph/shortestgraphpath;
while the test case is working without any problems in eclipse.
Hint: in eclipse, shortestgraphpath was added in Referenced Libraries.
You need to the jar file containing shortestgraphpath to java class path.
java -cp junit-4.8.1.jar;test\Dijkstra; test\Dijkstra\bin org.junit.runner.JUnitCore Data0PathTest00
The class path is the value that you pass to java with -cp so in your question you just supply junitand your compiled classes.
Try updating it with the jar file with the missing class.
java -cp junit-4.8.1.jar;<path to jar file>;test\Dijkstra;test\Dijkstra\bin org.junit.runner.JUnitCore Data0PathTest00
You might have to add additional jar files as well. I recommend that you take a look at some build tool to help you build and run your java applications for example Maven, Gradle, Buildr.
A program of mine (written in Scala 2.8) works fine when launched by means of NetBeans IDE. But when I try to run it from outside, with "java- jar", it says "Exception in thread "main" java.lang.NoClassDefFoundError: scala/ScalaObject...". Putting all the libraries, incl. Scala runtime inside the same dir as the jar to be run doesn't help. If i try to run the jar with scala itself, it complains that it can't decode it as utf-8 (it expects a scala source rather than a jar, I suppose). So how do I run a Scala application at all?
UPDATE: For those who come here later having the same question I'd recommend to read comments under barjak's answer (including those latest ones hidden), the answer is there. VonC also gives some interesting links on the subject.
The -jar and -classpath of the java command are mutually exclusive : you can't do java -jar YourScalaProg.jar -classpath scala-library.jar
If you want to run your application with java -jar, then the full classpath must be specified in the Class-Path section of the jar's manifest.
You can run your application using only -classpath, like that : java -classpath YourScalaProg.jar:scala-library.jar your.package.MainClass.
Are you using scala-library.jar as described in Adventures with Scala blog post?
java -classpath scala-library.jar:. YourClass
or:
java -classpath scala-library.jar:yourApp.jar YourClass
Where YourClass is was your scalac compiled Scala code.
You will find the same scala-library.jar used in the SO question "Creating a jar file from a Scala file" (or in the blog post "the not so elegant way of creating an executable jar from scala code").