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Run Java Maven project with Linux command line

I have a Java project that prints "Hello world !". It runs well under Eclipse/Windows and on a Linux server with the command:
java MyClass.java; javac MyClass
Now that I have converted the project to a Maven project it's still running fine in Eclipse, but I can't find how to run it with a Linux command. I tried many answers that I found on forums but none work for me.
Here is an example of what I tested:
mvn package install;
cd target;
java -cp myApp-0.0.1-SNAPSHOT.jar mypackage.Mylass;
This results to an error:
Error: Could not find or load main class mypackage.Mylass
So, how can I run the Maven code on Linux without generating a jar file or at least make it work with a command line?

i finally managed to make it work thanks to all the answers.
here is what i did
i moved my Main class to the outside of packages and deleted/regenerated a new POM file with
<manifest>
<mainClass>Myclass</mainClass>
</manifest>
but i got some dependency errors so i generated a jar file with the dependency by adding maven plugin jar-with-dependencies
so here is what the build part of my POM file looks like now
....
</dependencyManagement>
<build>
<sourceDirectory>src</sourceDirectory>
<plugins>
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.0</version>
<configuration>
<source>1.7</source>
<target>1.7</target>
</configuration>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-jar-plugin</artifactId>
<configuration>
<archive>
<manifest>
<mainClass>MyClass</mainClass>
</manifest>
</archive>
</configuration>
</plugin>
<plugin>
<artifactId>maven-assembly-plugin</artifactId>
<version>3.0.0</version>
<configuration>
<descriptorRefs>
<descriptorRef>jar-with-dependencies</descriptorRef>
</descriptorRefs>
<archive>
<manifest>
<mainClass>MyClass</mainClass>
</manifest>
</archive>
</configuration>
<executions>
<execution>
<id>make-assembly</id> <!-- this is used for inheritance merges -->
<phase>package</phase> <!-- bind to the packaging phase -->
<goals>
<goal>single</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</build>
and here is how i execute it .
rm -rf target/ #delete old generated files
mvn install package # generate new jar files
java -jar target/App-0.0.1-SNAPSHOT-jar-with-dependencies.jar # execution
i hope this can save someone else's time
thanks for your help

You've specify a main class in the manifest of myApp-0.0.1-SNAPSHOT.jar
Add the next snippet of code to your pom file.
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-jar-plugin</artifactId>
<configuration>
<archive>
<manifest>
<mainClass>mypackage.Mylass</mainClass>
</manifest>
</archive>
</configuration>
</plugin>
</plugins>
</build>
This's the complete pom.file
http://maven.apache.org/maven-v4_0_0.xsd">
4.0.0
com.mycompany.app
my-app
jar
1.0-SNAPSHOT
my-app
http://maven.apache.org
junit
junit
3.8.1
test
<dependency>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.6.1</version>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-jar-plugin</artifactId>
<configuration>
<archive>
<manifest>
<mainClass>com.mycompany.app.App</mainClass>
</manifest>
</archive>
</configuration>
</plugin>
</plugins>
</build>

Can you confirm the class name you can trying to run ?
As per your comment, originally ran the class using below command.
java MyClass.java; javac MyClass - here the class name is MyClass
After maven install, it should be invoked using
mvn package install;
cd target;
java -cp myApp-0.0.1-SNAPSHOT.jar mypackage.MyClass;

No main manifest attribute error when running jar

I have create a maven project. It is running fine. Now i want to run my code through jar. After maven build i got a jar file in .m2 folder. When I try to run this jar using
java -jar "jar path"
getting no main manifest attribute, in "jar path".
My POM.xml is
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.3</version>
<configuration>
<source>1.8</source>
<target>1.8</target>
</configuration>
</plugin>
<plugin>
<groupId>org.codehaus.mojo</groupId>
<artifactId>exec-maven-plugin</artifactId>
<version>1.2.1</version>
<configuration>
<mainClass>main.Application</mainClass>
</configuration>
</plugin>
</plugins>
</build>
Please suggest how to get over rid of the problem.

Now i want to run my code through jar
exec-maven-plugin is for executing a program during a maven build.
You don't want it.
And as a side note, you don't have specified any goal for it.
So, it will do nothing.
You want to package your jar in a way that it is executable.
So use rather the maven-jar-plugin :
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-jar-plugin</artifactId>
<configuration>
<archive>
<manifest>
<mainClass>main.Application</mainClass>
</manifest>
</archive>
</configuration>
</plugin>
To create a JAR with dependencies specified in the pom, instead of, use the maven-assembly-plugin with the jar-with-dependencies descriptorRef:
<build>
<plugins>
<plugin>
<artifactId>maven-assembly-plugin</artifactId>
<configuration>
<archive>
<manifest>
<mainClass>main.Application</mainClass>
</manifest>
</archive>
<descriptorRefs>
<descriptorRef>jar-with-dependencies</descriptorRef>
</descriptorRefs>
</configuration>
</plugin>
</plugins>
</build>

scala maven plugin not packaging scala files into jar

I'm new to maven and currently try to assemble a scala project with it. Project structure:
dir
|
|--src/main/java
|
|--src/main/scala
|
|--pom.xml
I was kind of surprised that classes compiled from *.java end up in jar, but one compiled from *.scala do not. I added these plugins to pom.xml
<plugins>
<plugin>
<groupId>net.alchim31.maven</groupId>
<artifactId>scala-maven-plugin</artifactId>
<version>3.1.3</version>
</plugin>
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<configuration>
<source>1.8</source>
<target>1.8</target>
</configuration>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-jar-plugin</artifactId>
<version>2.4</version>
<configuration>
<archive>
<manifest>
<addClasspath>true</addClasspath>
<classpathPrefix>lib/</classpathPrefix>
<mainClass>HelloWorld</mainClass>
</manifest>
</archive>
</configuration>
</plugin>
</plugins>
I though maven-jar-plugin is responsible for assembling jar files. But for some reason, it does not add scala-compiled classes.
QUESTION: Who adds .class file into a final jar after executing mvn install? How to add .class-files compiled with scala compiler?

mvn package will build your jar, however maven-compiler-plugin will only compile your java source files not your scala source files. Scala-maven-plugin can be used to compile both java and scala sources.
I wrote a blog post on this a while ago, that may help http://blog.rizvn.com/2016/04/scala-and-maven.html
You will need to tell maven about src/main/scala, since you are putting your scala code under src/main/java. This is done through the build section like so:
<build>
<sourceDirectory>src/main/scala</sourceDirectory>
<testSourceDirectory>src/test/scala</testSourceDirectory>
...
</build>

Can you try something like this, using "scala-maven-plugin" instead. Then execute maven goal : mvn clean package
<build>
<sourceDirectory>${basedir}/src</sourceDirectory>
<resources>
<resource>
<directory>${basedir}/src/test/resources</directory>
</resource>
</resources>
<plugins>
<plugin>
<groupId>net.alchim31.maven</groupId>
<artifactId>scala-maven-plugin</artifactId>
<version>${scala-maven-plugin.version}</version>
<configuration>
<sourceDir>${basedir}/src</sourceDir>
<outputDir>${basedir}/target/classes</outputDir>
</configuration>
<executions>
<execution>
<id>scala-compile-first</id>
<phase>process-resources</phase>
<goals>
<goal>compile</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>

How to instruct maven to automatically add dependency jars when they include a artifact that i created?

Well i have reusable code which i developed using Maven and the result artifact is a JAR.
Now to use it in another project , i have simply added the this dependency to that project's POM.xml,
but maven is not auto detecting and including the dependencies for the jar.
How do i go about do this ?
Appreciate any pointers in this regard .

You should try to build the developed(reusable) code with dependencies. I'm not quite sure if this will help (I had some issues with the build with dependencies, too), but I think it's worth a try.
So you should add this to the pom.xml (of the reusable project):
<build>
...
<plugins>
...
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-jar-plugin</artifactId>
<configuration>
<archive>
<manifest>
<addClasspath>true</addClasspath>
<mainClass>fully.qualified.MainClass</mainClass>
</manifest>
</archive>
</configuration>
</plugin>
<plugin>
<artifactId>maven-assembly-plugin</artifactId>
<configuration>
<descriptorRefs>
<descriptorRef>jar-with-dependencies</descriptorRef>
</descriptorRefs>
</configuration>
</plugin>
</plugins>
</build>
For details, have a look at this question and the maven-documenation

I solved this by manually adding the pom file for the jar I created.
[file structure]
GroupIdFolder
ArtifactIdFolder
VersionFolder
ownjar.jar [artifact I created]
ownjar.pom [file I mannually created]
Then in the .pom file put in the dependencies.
<project>
<dependencies>
<dependency>
<groupId>commons-collections</groupId>
<artifactId>commons-collections</artifactId>
<version>3.2.1</version>
</dependency>
</dependencies>
</project>

Add subversion revision to war manifest using maven2

I want to find a maven native (i.e. without calling external programs) to inject the svn revision in the war manifest.
Does anybody know a way to do that?
I found mention to how to add the subversion revision to manifests in jar files but not with war files.
I searched SO but could not find this issue specifically.

I want to find a maven native (i.e. without calling external programs) to inject the svn revision in the war manifest.
This is possible with the Build Number Maven Plugin using the svnjava provider:
If you need to execute the plugin on
machine without any svn in the path
you can configure the mojo to use the
svnjava provider.
<build>
<plugins>
<plugin>
<groupId>org.codehaus.mojo</groupId>
<artifactId>buildnumber-maven-plugin</artifactId>
<version>1.0-beta-3</version>
<executions>
<execution>
<phase>validate</phase>
<goals>
<goal>create</goal>
</goals>
</execution>
</executions>
<configuration>
<doCheck>true</doCheck>
<doUpdate>true</doUpdate>
<providerImplementations>
<svn>javasvn</svn>
</providerImplementations>
</configuration>
</plugin>
</plugins>
</build>
The Build Number Maven Plugin sets the build number in the ${buildNumber} property that you can then use in your POM.
I found mention to how to add the subversion revision to manifests in jar files but not with war files.
Then, to add the build number in the MANIFEST of a war, configure the plugin as mentioned in the Usage page:
<build>
...
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-war-plugin</artifactId>
<version>2.0.2</version>
<configuration>
<archive>
<manifest>
<addDefaultImplementationEntries>true</addDefaultImplementationEntries>
</manifest>
<manifestEntries>
<Implementation-Build>${buildNumber}</Implementation-Build>
</manifestEntries>
</archive>
</configuration>
</plugin>
</plugins>
</build>

Try this. About halfway down, look for maven-war-plugin
<build>
...
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-war-plugin</artifactId>
<version>2.0.2</version>
<configuration>
<archive>
<manifest>
<addDefaultImplementationEntries>true</addDefaultImplementationEntries>
</manifest>
<manifestEntries>
<Implementation-Build>${buildNumber}</Implementation-Build>
</manifestEntries>
</archive>
</configuration>
</plugin>
</plugins>
</build>