@Override
    public String toString() {
        if (subquery == SubqueryBitmap.DEFAULT_VALUE) {
            return "" + docId;
        } else {
            return "[" + docId + ",0x" + Long.toHexString(subquery) + "]";
        }
    }
Represents a hit from the predicate search algorithm.
Each hit is associated with a subquery bitmap,
indicating which subqueries the hit represents.

@author Magnar Nedland
predicate-search/src/main/java/com/yahoo/search/predicate/Hit.java