I'm getting the above error when I try to execute the following command.
java -cp target/helloHBase-1.0-SNAPSHOT.jar HBaseIA.TwitBase.UsersTool add TheRealMT "Mark Twain" samuel@clemens.org abc123
I'm using IntelliJIdea IDE and all my maven 'clean', 'install' and 'package' commands give "Build Success" message. 
The directory structure of the project is provided below. I've already imported the hbase jar files to my project as external libraries in IntelliJ.
Complete error:
Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/hadoop/hbase/client/HTablePool
        at HBaseIA.TwitBase.UsersTool.main(UsersTool.java:22)
Caused by: java.lang.ClassNotFoundException: org.apache.hadoop.hbase.client.HTablePool
        at java.net.URLClassLoader.findClass(URLClassLoader.java:382)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
        at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:349)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
        ... 1 more
pom.xml provided below.
<?xml version="1.0" encoding="UTF-8"?>
<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>hbase</groupId>
    <artifactId>helloHBase</artifactId>
    <version>1.0-SNAPSHOT</version>
    <dependencies>
        <!-- https://mvnrepository.com/artifact/org.apache.hbase/hbase-client -->
        <dependency>
            <groupId>org.apache.hbase</groupId>
            <artifactId>hbase-client</artifactId>
            <version>1.1.2</version>
        </dependency>
    </dependencies>  
</project>

