void resetCachedFromAndTo() {
        cachedFrom = Integer.MIN_VALUE;
        cachedTo = Integer.MIN_VALUE;
        if (getParent() instanceof SpanList) {
            ((SpanList) getParent()).resetCachedFromAndTo();
        }
    }
Returns the character index where this {@link SpanNode} ends (exclusive), i.e.&nbsp;the greatest {@link com.yahoo.document.annotation.SpanNode#getTo()} of all children.

@return the greatest getTo() of all children, or -1 if this SpanList has no children.
document/src/main/java/com/yahoo/document/annotation/SpanList.java