Method Advance

Advances to the first beyond the current whose document number is greater than or equal to target. Returns the current document number or NO_MORE_DOCS if there are no more docs in the set.

Behaves as if written:

int advance(int target) {
    int doc;
    while ((doc = nextDoc()) < target) {
    }
    return doc;
}

Some implementations are considerably more efficient than that.

NOTE: certain implemenations may return a different value (each time) if called several times in a row with the same target.

NOTE: this method may be called with NO_MORE_DOCS for efficiency by some Scorers. If your implementation cannot efficiently determine that it should exhaust, it is recommended that you check for that value in each call to this method.

NOTE: after the iterator has exhausted you should not call this method, as it may result in unpredicted behavior.