org.apache.lucene.util

Class DocIdBitSet

java.lang.Object

org.apache.lucene.search.DocIdSet

org.apache.lucene.util.DocIdBitSet

All Implemented Interfaces:

Accountable, Bits

public class DocIdBitSet
extends DocIdSet
implements Bits

Simple DocIdSet and DocIdSetIterator backed by a BitSet

Nested Class Summary

Nested classes/interfaces inherited from interface org.apache.lucene.util.Bits

Bits.MatchAllBits, Bits.MatchNoBits

Field Summary

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

EMPTY

Fields inherited from interface org.apache.lucene.util.Bits

EMPTY_ARRAY

Constructor Summary

Constructors

Constructor and Description
DocIdBitSet(BitSet bitSet)

Method Summary

Methods

Modifier and Type	Method and Description
Bits	bits() Optionally provides a Bits interface for random access to matching documents.
boolean	get(int index) Returns the value of the bit with the specified index.
BitSet	getBitSet() Returns the underlying BitSet.
boolean	isCacheable() This DocIdSet implementation is cacheable.
DocIdSetIterator	iterator() Provides a DocIdSetIterator to access the set.
int	length() Returns the number of bits in this set
long	ramBytesUsed() Return the memory usage of this object in bytes.

Methods inherited from class java.lang.Object

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

Constructor Detail

DocIdBitSet

public DocIdBitSet(BitSet bitSet)

Method Detail

iterator

public DocIdSetIterator iterator()

Description copied from class: DocIdSet

Provides a DocIdSetIterator to access the set. This implementation can return null if there are no docs that match.

Specified by:

iterator in class DocIdSet

bits

public Bits bits()

Description copied from class: DocIdSet

Optionally provides a Bits interface for random access to matching documents.

Overrides:

bits in class DocIdSet

Returns:

null, if this DocIdSet does not support random access. In contrast to DocIdSet.iterator(), a return value of null does not imply that no documents match the filter! The default implementation does not provide random access, so you only need to implement this method if your DocIdSet can guarantee random access to every docid in O(1) time without external disk access (as Bits interface cannot throw IOException). This is generally true for bit sets like FixedBitSet, which return itself if they are used as DocIdSet.

isCacheable

public boolean isCacheable()

This DocIdSet implementation is cacheable.

Overrides:

isCacheable in class DocIdSet

getBitSet

public BitSet getBitSet()

Returns the underlying BitSet.

get

public boolean get(int index)

Description copied from interface: Bits

Returns the value of the bit with the specified index.

Specified by:

get in interface Bits

Parameters:

index - index, should be non-negative and < Bits.length(). The result of passing negative or out of bounds values is undefined by this interface, just don't do it!

Returns:

true if the bit is set, false otherwise.

length

public int length()

Description copied from interface: Bits

Returns the number of bits in this set

Specified by:

length in interface Bits

ramBytesUsed

public long ramBytesUsed()

Description copied from interface: Accountable

Return the memory usage of this object in bytes. Negative values are illegal.

Specified by:

ramBytesUsed in interface Accountable

Overrides:

ramBytesUsed in class DocIdSet