public static boolean isBlankJson(final Object obj) {
        if (obj == null) {
            return true;
        }
        if(obj instanceof Collection) {
            return (((Collection) obj).size() == 0);
        }
        if(obj instanceof Map) {
            return (((Map) obj).size() == 0);
        }
        throw new UnsupportedOperationException("map or list is supported, got ${obj?obj.getClass():null}");
    }
public static boolean isBlankJson ( final Object obj ) { if ( obj == null ) { return true ; } if ( obj instanceof Collection ) { return ( ( ( Collection ) obj ) . size ( ) == 0 ) ; } if ( obj instanceof Map ) { return ( ( ( Map ) obj ) . size ( ) == 0 ) ; } throw new UnsupportedOperationException ( "map or list is supported, got ${obj?obj.getClass():null}" ) ; }
Given a json document checks if its jst blank doc, i.e. [] or {}

@param obj source
@return true if the json doc is [] or {}