Exception in thread "main" java.lang.NoClassDefFoundError: org/ejml/simple/SimpleBase

It seems it's missing the Java library Efficient Java Matrix Library(ejml), so I have downloaded from the sources here. I'm creating Maven Jar executable file and running on Openstack EDP Spark environment.

I'm having trouble figuring out how to solve this java.lang.NoClassDefFoundError: org/ejml/simple/SimpleBase

I also tried ejml version 0.23, 0.25, 0.27, 0.30, 0.31.

Exception in thread "main" java.lang.NoClassDefFoundError: org/ejml/simple/SimpleBase
    at java.lang.Class.forName0(Native Method)
    at java.lang.Class.forName(Class.java:195)
    at org.openstack.sahara.edp.SparkWrapper.main(SparkWrapper.java:17)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at org.apache.spark.deploy.SparkSubmit$.org$apache$spark$deploy$SparkSubmit$$runMain(SparkSubmit.scala:731)
    at org.apache.spark.deploy.SparkSubmit$.doRunMain$1(SparkSubmit.scala:181)
    at org.apache.spark.deploy.SparkSubmit$.submit(SparkSubmit.scala:206)
    at org.apache.spark.deploy.SparkSubmit$.main(SparkSubmit.scala:121)
    at org.apache.spark.deploy.SparkSubmit.main(SparkSubmit.scala)
Caused by: java.lang.ClassNotFoundException: org.ejml.simple.SimpleBase
    at java.net.URLClassLoader$1.run(URLClassLoader.java:359)
    at java.net.URLClassLoader$1.run(URLClassLoader.java:348)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(URLClassLoader.java:347)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:425)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:358)