@Override
    public boolean equals(Object o) {
        if ( ! super.equals(o)) return false;
        var other = (UriItem)o;
        if ( this.startAnchorDefault != other.startAnchorDefault) return false;
        if ( this.endAnchorDefault != other.endAnchorDefault) return false;
        if ( ! Objects.equals(this.sourceString, other.sourceString)) return false;
        return true;
    }
Returns the canonical form of the tokens of this: Either the source string, or if none
each token except the start and end anchor separated by space
container-search/src/main/java/com/yahoo/prelude/query/UriItem.java