Commons Logging - ClassNotFoundException - apache

Question

For whatever reason I can't seem to run my jar file without receiving a ClassNotFound Exception. I am new to Maven, so I believe the issue could be caused by my POM.XML file. Allow me to elaborate. I have isolated the problem to an example HelloWorld log.
package com;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
public class HelloLog {
public static Log log = LogFactory.getLog(HelloLog.class);
public static void main(String[] args){
log.info("Hello World!");
}
}
I have also simplified my pom.xml to only two dependencies.
<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>--MygroupId--</groupId>
<artifactId>--MyArtID--</artifactId>
<version>--MyVer--</version>
<dependencies>
<dependency>
<groupId>commons-logging</groupId>
<artifactId>commons-logging</artifactId>
<version>1.1.3</version>
</dependency>
<dependency>
<groupId>org.hibernate.javax.persistence</groupId>
<artifactId>hibernate-jpa-2.0-api</artifactId>
<version>1.0.1.Final</version>
</dependency>
</dependencies>
<build>
<sourceDirectory>src</sourceDirectory>
<resources>
<resource>
<directory>src</directory>
<excludes>
<exclude>**/*.java</exclude>
</excludes>
</resource>
</resources>
<plugins>
<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>com.HelloLog</mainClass>
</manifest>
</archive>
</configuration>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.1</version>
<configuration>
<verbose>true</verbose>
<fork>true</fork>
<compilerVersion>1.6</compilerVersion>
</configuration>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-dependency-plugin</artifactId>
<version>2.5.1</version>
<executions>
<execution>
<id>copy-dependencies</id>
<phase>package</phase>
<goals>
<goal>copy-dependencies</goal>
</goals>
<configuration>
<outputDirectory>
${project.build.directory}/dependency-jars/
</outputDirectory>
<overWriteReleases>false</overWriteReleases>
<overWriteSnapshots>false</overWriteSnapshots>
<overWriteIfNewer>true</overWriteIfNewer>
</configuration>
</execution>
</executions>
</plugin>
</plugins>
<pluginManagement>
<plugins>
<!--This plugin's configuration is used to store Eclipse m2e settings only. It has no influence on the Maven build itself.-->
<plugin>
<groupId>org.eclipse.m2e</groupId>
<artifactId>lifecycle-mapping</artifactId>
<version>1.0.0</version>
<configuration>
<lifecycleMappingMetadata>
<pluginExecutions>
<pluginExecution>
<pluginExecutionFilter>
<groupId>
org.apache.maven.plugins
</groupId>
<artifactId>
maven-dependency-plugin
</artifactId>
<versionRange>
[2.5.1,)
</versionRange>
<goals>
<goal>copy-dependencies</goal>
</goals>
</pluginExecutionFilter>
<action>
<ignore></ignore>
</action>
</pluginExecution>
</pluginExecutions>
</lifecycleMappingMetadata>
</configuration>
</plugin>
</plugins>
</pluginManagement>
</build>
</project>
When I run the HelloLog class in Eclipse all is good and I get the expected output. However, when I execute java -jar on the Jar file I receive the ClasNotFoundException on LogFactory at line 7. The jar file is accompanied in the target folder with the dependency-jars folder. The dependency-jars folder holds these two dependencies.

Answer 1

Found the problem, it was Maven related. Hadn't noticed my classpathPrefix was set as lib. Where as I outputted the dependencies to dependency-jars.