Maven exec works, but java -jar does not

Question

I have simple maven project with only one dependency. I can install it and run it command-line via Exec Maven Plugin:

mvn exec:java -D"exec.mainClass"="com.MyClass"

After packaging maven generates a .jar file in my directory. With a help of Maven JAR Plugin I made its manifest to know my main method class. It looks like:

...
Created-By: Apache Maven 3.3.1
Build-Jdk: 1.8.0_66
Main-Class: com.MyClass

Now I want to run this .jar file like regular java executable using java command, but after doing the following:

java -jar myFile.jar

it gives an error java.lang.NoClassDefFoundError concerning my only dependency.

How can I make maven to add all dependencies into my executable jar file?

Answer 1

You could use the Apache Maven Assembly Plugin, in order to create a jar with all its dependencies, so your pom.xml should be like the following:

<plugin>
    <artifactId>maven-assembly-plugin</artifactId>
    <executions>
        <execution>
            <phase>package</phase>
            <goals>
                <goal>single</goal>
            </goals>
        </execution>
    </executions>
    <configuration>
        <archive>
            <manifest>
                <addClasspath>true</addClasspath>
                <classpathPrefix>lib/</classpathPrefix>
                <mainClass>mypackage.myclass</mainClass>
            </manifest>
        </archive>
        <descriptorRefs>
            <descriptorRef>jar-with-dependencies</descriptorRef>
        </descriptorRefs>
    </configuration>
</plugin>

I hope it helps you, bye.