src/main/java/com/simpligility/maven/plugins/android/standalonemojos/UIAutomatorMojo.java
protected static String buildSpaceSeparatedString( String[] lines )
    {
        if ( lines == null || lines.length == 0 )
        {
            return null;
        }

        return StringUtils.join( lines, " " );
    }
protected static String buildSpaceSeparatedString( String[] lines )
    {
        if ( lines == null || lines.length == 0 )
        {
            return null;
        }

        return StringUtils.join( lines, " " );
    }
Helper method to build a comma separated string from a list. Blank strings are filtered out

@param lines
A list of strings
@return Comma separated String from given list