NewFieldInvertState Creates {code FieldInvertState} for the specified field name and values for all fields.

CUSTOM Sort using a custom cmp.

DOC Sort by document number (index order).

DOUBLE Sort using term values as encoded Doubles.

The total hit count is equal to value.

FLOAT Sort using term values as encoded Floats.

The total hit count is greater than or equal to value.

INT Sort using term values as encoded Integers.

LONG Sort using term values as encoded Longs.

OccurFilter Like OccurMust except that these clauses do not participate in scoring.

OccurMust Use this operator for clauses that must appear in the matching documents.

OccurMustNot Use this operator for clauses that must not appear in the matching documents.

OccurShould Use this operator for clauses that should appear in the matching documents.

REWRITEABLE Force rewriting of SortField using rewrite(IndexSearcher) before it can be used for sorting.

SCORE // Sort by document score (relevance).

SEEK_STATUS_END The term was not found, and the end of iteration was hit.

SEEK_STATUS_FOUND The precise term was found.

SEEK_STATUS_NOT_FOUND A different term was found after the requested term.

STRING Sort using term values as Strings.

STRING_VAL Sort using term values as Strings, but comparing by item (using String.compareTo) for all comparisons.

BufferedUpdates Holds buffered deletes and updates, by docID, term or query for a single segment.

FieldInvertState This class tracks the number and position / offset parameters of terms being added to the index.

FieldUpdatesBuffer This class efficiently buffers numeric and binary field updates and stores terms, values and metadata in a memory efficient way without creating large amounts of objects.

MergeState Holds common state used during segment merging.

SegmentReadState Holder class for common parameters used during read.

SegmentWriteState Holder class for common parameters used during write.

TotalHits Description of the total number of hits of a query.

BinaryDocValues A per-document numeric item.

Bits Interface for Bitset-like structures.

BulkScorer This class is used to Score a range of documents at once, and is returned by Weight.bulkScorer.

CacheHelper A utility class that gives hooks in order to help build a cache based on the data that is contained in this index.

Codec Encodes/decodes an inverted index segment.

Collector Expert: Collectors are primarily meant to be used to gather raw results from a search, and implement sorting or custom result filtering, collation, etc.

ComparableProvider Used for sorting documents across segments 用于跨多个段（segment）进行文档排序.

CompositeReader Instances of this reader type can only be used to get stored fields from the underlying LeafReaders, but it is not possible to directly retrieve postings.

CompoundDirectory A read-only Directory that consists of a view over a compound file.

CompoundFormat Encodes/decodes compound files lucene.experimental.

DirectoryReader is an implementation of CompositeReader that can read indexes in a Directory.

DocComparator A comparator of doc IDs, used for sorting documents within a segment 用于段内文档的排序.

A DocIdSet contains a set of doc ids.

DocMap A permutation of doc IDs.

DocValuesConsumer Abstract API that consumes numeric, binary and sorted docvalues.

DocValuesFormat Encodes/decodes per-document values.

DocValuesProducer Abstract API that produces numeric, binary, sorted, sortedset, and sortednumeric docvalues.

DocValuesUpdate An in-place update to a DocValues field.

FieldComparator Expert: a FieldComparator compares hits so as to determine their sort order when collecting the top results with TopFieldCollector.

FieldComparatorSource Provides a FieldComparator for custom field sorting.

FieldInfosFormat Encodes/decodes FieldInfos lucene.experimental.

Fields Provides a Terms index for fields that have it, and lists which fields do.

FieldsProducer Sole constructor.

ImpactsEnum Extension of PostingsEnum which also provides information about upcoming impacts.

ImpactsSource Source of Impacts.

IndexCommit Expert: represents a single commit into an index as seen by the IndexDeletionPolicy or IndexReader.

IndexReader is an abstract class, providing an interface for accessing a point-in-time view of an index.

IndexReaderContext A struct like class that represents a hierarchical relationship between IndexReader instances.

IndexSorter Handles how documents should be sorted in an index, both within a segment and between segments.

LeafCollector Collector decouples the score from the collected doc: the score computation is skipped entirely if it's not needed.

LeafFieldComparator Expert: comparator that gets instantiated on each leaf from a top-level FieldComparator instance.

Matches Reports the positions and optionally offsets of all matching terms in a query for a single document To obtain a MatchesIterator for a particular field, call GetMatches(String).

MatchesIterator An iterator over match positions (and optionally offsets) for a single document and field To iterate over the matches, call next() until it returns false, retrieving positions and/or offsets after each call.

NormsConsumer Abstract API that consumes normalization values.

NormsFormat Encodes/decodes per-document score normalization values.

NormsProducer Abstract API that produces field normalization values.

NumericDocValues A per-document numeric item.

PointsFormat Encodes/decodes indexed points.

PointsReader Abstract API to visit point values.

PointsWriter Abstract API to write points lucene.experimental.

PostingsEnum Iterates through the postings.

PostingsFormat Encodes/decodes terms, postings, and proximity data.

Query The abstract base class for queries.

QueryCache A cache for queries.

QueryCachingPolicy A policy defining which filters should be cached.

QueryVisitor Allows recursion through a query tree See Also: Query.visit(QueryVisitor).

Scorable Allows access to the Score of a Query 允许访问查询的分数.

Scorer Expert: Common scoring functionality for different types of queries.

SegmentCacheable Interface defining whether or not an object can be cached against a LeafReader Objects that depend only on segment-immutable structures such as Points or postings lists can just return true from isCacheable(LeafReaderContext) Objects that depend on doc values should return DocValues.isCacheable(LeafReaderContext, String...), which will check to see if the doc values fields have been updated.

SegmentInfoFormat Expert: Controls the format of the SegmentInfo (segment metadata file).

Similarity defines the components of Lucene scoring.

SimScorer Stores the weight for a query across the indexed collection.

SortedDocValues A per-document byte[] with presorted values.

SortedNumericDocValues A list of per-document numeric values, sorted according to Long.CompareFn(long, long).

SortedSetDocValues A multi-valued version of SortedDocValues.

Sorter Base class for sorting algorithms implementations.

SortField Stores information about how to sort documents by terms in an individual field.

SortFieldProvider Reads/Writes a named SortField from a segment info file, used to record index sorts.

StoredFieldsFormat Controls the format of stored fields.

StoredFieldsReader Codec API for reading stored fields.

StoredFieldsWriter Codec API for writing stored fields: 1.

TermsEnum DVFUIterator to seek (seekCeil(), seekExact()) or step through (next terms to obtain frequency information (docFreq), PostingsEnum or PostingsEnum for the current term (postings.

TermState Encapsulates all required internal state to position the associated TermsEnum without re-seeking.

TermVectorsFormat Controls the format of term vectors.

TermVectorsReader Codec API for reading term vectors: lucene.experimental.

TermVectorsWriter Codec API for writing term vectors: 1.

TwoPhaseIterator Returned by Scorer.TwoPhaseIterator() to expose an approximation of a DocIdSetIterator.

Weight Expert: Calculate query weights and build query scorers.

Occur Specifies how clauses are to occur in matching documents.

ScoreMode Different modes of search.

SeekStatus Represents returned result from seekCeil.

SortFieldType Specifies the type of the terms to be sorted, or special types such as CUSTOM.

TotalHitsRelation How the value should be interpreted.