Running a scala application in maven project - eclipse

Question

I am trying to use maven to handle dependencies in a scala project in Eclipse. But once the project is converted to maven, the application wont run anymore.
Here is the steps to reproduce :
1) new scala project
project name : test
finish
2) new scala object
name : hello_world
finish
3) hello_world.scala
package test
object hello_world {
def main(args: Array[String]) {
println("Hello world !!!")
}
}
4) run scala application
project : test
main class : test.hello_world
result : working, hello world is printed
5) right clic on project -> configure -> convert to mavem project
group id : test
artifact id : test
version : 0.0.1-SNAPSHOT
packaging : jar
finish
6) run scala application
project : test
main class : test.hello_world
result :
Error: Could not find or load main class test.hello_world
Versions details :
Eclipse 4.4.1
M2E 1.5.0
Scala IDE for Eclipse 4.0.0.nightly-2_11
Generated pom-xml :
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>test</groupId>
<artifactId>test</artifactId>
<version>0.0.1-SNAPSHOT</version>
<build>
<sourceDirectory>src</sourceDirectory>
<resources>
<resource>
<directory>src</directory>
<excludes>
<exclude>**/*.java</exclude>
</excludes>
</resource>
</resources>
<plugins>
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.1</version>
<configuration>
<source>1.8</source>
<target>1.8</target>
</configuration>
</plugin>
</plugins>
</build>
</project>

Answer 1

http://scala-tools.org/repo-releases is deprecated, here is a working pom.xml :
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>test</groupId>
<artifactId>test</artifactId>
<version>0.0.1-SNAPSHOT</version>
<repositories>
<repository>
<id>scala-tools.org</id>
<name>Scala-tools Maven2 Repository</name>
<url>https://oss.sonatype.org/content/groups/scala-tools/</url>
</repository>
</repositories>
<pluginRepositories>
<pluginRepository>
<id>scala-tools.org</id>
<name>Scala-tools Maven2 Repository</name>
<url>https://oss.sonatype.org/content/groups/scala-tools/</url>
</pluginRepository>
</pluginRepositories>
<dependencies>
<dependency>
<groupId>org.scala-lang</groupId>
<artifactId>scala-library</artifactId>
<version>2.11.4</version>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>3.8.1</version>
<scope>test</scope>
</dependency>
</dependencies>
<build>
<sourceDirectory>src</sourceDirectory>
<pluginManagement>
<plugins>
<plugin>
<groupId>net.alchim31.maven</groupId>
<artifactId>maven-scala-plugin</artifactId>
<version>3.2.0</version>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.1</version>
</plugin>
</plugins>
</pluginManagement>
<plugins>
<plugin>
<groupId>org.scala-tools</groupId>
<artifactId>maven-scala-plugin</artifactId>
<executions>
<execution>
<id>scala-compile-first</id>
<phase>process-resources</phase>
<goals>
<goal>add-source</goal>
<goal>compile</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</build>
</project>
To run the application :
run -> scala application
project : test
main class : test.hello_world

Answer 2

Your pom.xml should contain these parts (change the versions of course):
Repositories:
<repositories>
<repository>
<id>scala-tools.org</id>
<name>Scala-Tools Maven2 Repository</name>
<url>http://scala-tools.org/repo-releases</url>
</repository>
</repositories>
Plugin repositories:
<pluginRepositories>
<pluginRepository>
<id>scala-tools.org</id>
<name>Scala-Tools Maven2 Repository</name>
<url>http://scala-tools.org/repo-releases</url>
</pluginRepository>
</pluginRepositories>
Dependencies:
<dependencies>
<dependency>
<groupId>org.scala-lang</groupId>
<artifactId>scala-library</artifactId>
<version>${scala.version}</version>
</dependency>
</dependencies>
Build:
<build>
<pluginManagement>
<plugins>
<plugin>
<groupId>org.scala-tools</groupId>
<artifactId>maven-scala-plugin</artifactId>
<version>2.15.2</version>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.1</version>
</plugin>
</plugins>
</pluginManagement>
<plugins>
<plugin>
<groupId>org.scala-tools</groupId>
<artifactId>maven-scala-plugin</artifactId>
<executions>
<execution>
<id>scala-compile-first</id>
<phase>process-resources</phase>
<goals>
<goal>add-source</goal>
<goal>compile</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</build>

Answer 3

Go to
project properties->Select scala compiler->Select scala installation and change to scala-2.10->apply->close
Run
maven clean
Run Scala application
then you cant see the output in Console

Answer 4

May be mine is late reply but it may help some one, Below process fixed my issue.
Please do check whether your source folders is on build path or not. If your source folders is not in build path you can't see run as scala application in runas
To add your source to build path
1) Right click on project properties
2) In left side pane select Java Build Path and in source tab click on add folder and select your source folder and click ok