public static String getExternalVariable(String var)
    {
        String value = System.getProperty(var);
        if (StringUtilities.isEmpty(value))
        {
            value = System.getenv(var);
        }
        return StringUtilities.isEmpty(value) ? null : value;
    }
public static String getExternalVariable ( String var ) { String value = System . getProperty ( var ) ; if ( StringUtilities . isEmpty ( value ) ) { value = System . getenv ( var ) ; } return StringUtilities . isEmpty ( value ) ? null : value ; }
Fetch value from environment variable and if not set, then fetch from
System properties.  If neither available, return null.
@param var String key of variable to return