public class TermAllGroupsCollector extends AllGroupsCollector<BytesRef>
Implementation detail: an int hash set (SentinelIntSet) is used to detect if a group is already added to the total count. For each segment the int set is cleared and filled with previous counted groups that occur in the new segment.
|Constructor and Description|
Expert: Constructs a
|Modifier and Type||Method and Description|
Called once for every document matching a query, with the unbased document number.
This method is called before collecting
Returns the group values
getGroupCount, needsScores, setScorer
public TermAllGroupsCollector(String groupField, int initialSize)
groupField- The field to group by
initialSize- The initial allocation size of the internal int set and group list which should roughly match the total number of expected unique groups. Be aware that the heap usage is 4 bytes * initialSize.
public void collect(int doc) throws IOException
Note: The collection of the current segment can be terminated by throwing
CollectionTerminatedException. In this case, the last docs of the
LeafReaderContext will be skipped and
will swallow the exception and continue collection with the next leaf.
Note: This is called in an inner search loop. For good search performance,
implementations of this method should not call
IndexReader.document(int) on every hit.
Doing so can slow searches by an order of magnitude or more.
public Collection<BytesRef> getGroups()
This is an unordered collections of group values. For each group that matched the query there is a
representing a group value.