org.apache.lucene.search
Class FieldCacheDocIdSet

java.lang.Object
  org.apache.lucene.search.DocIdSet
      org.apache.lucene.search.FieldCacheDocIdSet

public abstract class FieldCacheDocIdSet
extends DocIdSet

Base class for DocIdSet to be used with FieldCache. The implementation of its iterator is very stupid and slow if the implementation of the matchDoc(int) method is not optimized, as iterators simply increment the document id until matchDoc(int) returns true. Because of this matchDoc(int) must be as fast as possible and in no case do any I/O.

NOTE: This API is for internal purposes only and might change in incompatible ways in the next release.

Field Summary

protected IndexReader

reader

Fields inherited from class org.apache.lucene.search.DocIdSet

EMPTY_DOCIDSET

Constructor Summary

FieldCacheDocIdSet(IndexReader reader)

Method Summary

boolean	isCacheable() this DocIdSet is cacheable, if it works solely with FieldCache and no TermDocs
DocIdSetIterator	iterator() Provides a DocIdSetIterator to access the set.
protected abstract boolean	matchDoc(int doc) this method checks, if a doc is a hit

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

reader

protected final IndexReader reader

Constructor Detail

FieldCacheDocIdSet

public FieldCacheDocIdSet(IndexReader reader)

Method Detail

matchDoc

protected abstract boolean matchDoc(int doc)

this method checks, if a doc is a hit

isCacheable

public final boolean isCacheable()

this DocIdSet is cacheable, if it works solely with FieldCache and no TermDocs

Overrides:

isCacheable in class DocIdSet

iterator

public final DocIdSetIterator iterator()
                                throws IOException

Description copied from class: DocIdSet

Provides a DocIdSetIterator to access the set. This implementation can return null or DocIdSet.EMPTY_DOCIDSET.iterator() if there are no docs that match.

Specified by:

iterator in class DocIdSet

Throws:

IOException