Error when running "walkmod plugins" command after installation

[Adilson Oliveira Cruz]

 Hi all,

 I have just installed Walkmod on my Ubuntu 16.04 but when I try to run "walkmog plugins" I get the following error:

$walkmog plugins
 INFO [main] - Java version: 1.8.0_121
 INFO [main] - Java Home: /usr/lib/jvm/java-8-oracle/jre
 INFO [main] - OS: Linux, Vesion: 4.4.0-78-generic
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                     _    _       _ _   ___  ___          _                    
                    | |  | |     | | |  |  \/  |         | |                   
                    | |  | | __ _| | | _| .  . | ___   __| |                   
                    | |/\| |/ _` | | |/ / |\/| |/ _ \ / _` |                   
                    \  /\  / (_| | |   <| |  | | (_) | (_| |                   
                     \/  \/ \__,_|_|_|\_\_|  |_/\___/ \__,_|                   
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An open source tool to apply code conventions
version 3.0 - February 2017 -
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Exception in thread "main" Invalid plugins URL - org.walkmod.util.location.LocationImpl@3e57cd70
    at org.walkmod.commands.PrintPluginsCommand.execute(PrintPluginsCommand.java:172)
    at org.walkmod.WalkModDispatcher.execute(WalkModDispatcher.java:172)
    at org.walkmod.WalkModDispatcher.main(WalkModDispatcher.java:197)
Caused by: java.lang.NullPointerException
    ... 3 more

 I have a proxy with authentication so I configured the walkmod-3.0.0/config/ivysettings.xml accordingly but I still get the same error:

<ivysettings>
 <property name="http.proxyHost" value="my-proxy-IP"/>
 <property name="http.proxyPort" value="my-proxy-port"/>
 <property name="http.proxyUser" value="my-username"/>
 <property name="http.proxyPassword" value="my-password"/>
...

 I use Netstat to monitor the connection from Walkmod and I get the following output:
$netstat -natp | grep java
tcp6       0      1 10.71.0.180:43264       207.223.241.72:443      SYN_SENT    15292/java

 This is all the information that I can give you all.

 Can somebody help me?

 Thanks in advanced,

 Adilson Oliveira Cruz