Class DocIdSet

A DocIdSet contains a set of doc ids. Implementing classes must only implement GetIterator() to provide access to the set.

Inheritance

System.Object

DocIdSet

FieldCacheDocIdSet

FilteredDocIdSet

DocIdBitSet

FixedBitSet

OpenBitSet

EliasFanoDocIdSet

PForDeltaDocIdSet

WAH8DocIdSet

Namespace: Lucene.Net.Search

Assembly: Lucene.Net.dll

Syntax

public abstract class DocIdSet : object

Properties

Bits

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

Declaration

public virtual IBits Bits { get; }

Property Value

Type

Description

IBits

null, if this DocIdSet does not support random access. In contrast to GetIterator(), 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 IBits interface cannot throw ). This is generally true for bit sets like FixedBitSet, which return itself if they are used as DocIdSet.

IsCacheable

This method is a hint for CachingWrapperFilter, if this DocIdSet should be cached without copying it. The default is to return false. If you have an own DocIdSet implementation that does its iteration very effective and fast without doing disk I/O, override this property and return true.

Declaration

public virtual bool IsCacheable { get; }

Property Value

Type	Description
System.Boolean

Methods

GetIterator()

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

Declaration

public abstract DocIdSetIterator GetIterator()

Returns

Type	Description
DocIdSetIterator

NewAnonymous(Func<DocIdSetIterator>)

Creates a new instance with the ability to specify the body of the GetIterator() method through the getIterator parameter. Simple example:

    var docIdSet = DocIdSet.NewAnonymous(getIterator: () =>
    {
        OpenBitSet bitset = new OpenBitSet(5);
        bitset.Set(0, 5);
        return new DocIdBitSet(bitset);
    });

LUCENENET specific

Declaration

public static DocIdSet NewAnonymous(Func<DocIdSetIterator> getIterator)

Parameters

Type	Name	Description
Func<DocIdSetIterator>	getIterator	A delegate method that represents (is called by) the GetIterator() method. It returns the DocIdSetIterator for this DocIdSet.

Returns

Type	Description
DocIdSet	A new Lucene.Net.Search.DocIdSet.AnonymousDocIdSet instance.

NewAnonymous(Func<DocIdSetIterator>, Func<IBits>)

Creates a new instance with the ability to specify the body of the GetIterator() method through the getIterator parameter and the body of the Bits property through the bits parameter. Simple example:

    var docIdSet = DocIdSet.NewAnonymous(getIterator: () =>
    {
        OpenBitSet bitset = new OpenBitSet(5);
        bitset.Set(0, 5);
        return new DocIdBitSet(bitset);
    }, bits: () => 
    {
        return bits;
    });

LUCENENET specific

Declaration

public static DocIdSet NewAnonymous(Func<DocIdSetIterator> getIterator, Func<IBits> bits)

Parameters

Type	Name	Description
Func<DocIdSetIterator>	getIterator	A delegate method that represents (is called by) the GetIterator() method. It returns the DocIdSetIterator for this DocIdSet.
Func<IBits>	bits	A delegate method that represents (is called by) the Bits property. It returns the IBits instance for this DocIdSet.

Returns

Type	Description
DocIdSet	A new Lucene.Net.Search.DocIdSet.AnonymousDocIdSet instance.

NewAnonymous(Func<DocIdSetIterator>, Func<IBits>, Func<Boolean>)

Creates a new instance with the ability to specify the body of the GetIterator() method through the getIterator parameter and the body of the Bits property through the bits parameter. Simple example:

    var docIdSet = DocIdSet.NewAnonymous(getIterator: () =>
    {
        OpenBitSet bitset = new OpenBitSet(5);
        bitset.Set(0, 5);
        return new DocIdBitSet(bitset);
    }, bits: () => 
    {
        return bits;
    }, isCacheable: () =>
    {
        return true;
    });

LUCENENET specific

Declaration

public static DocIdSet NewAnonymous(Func<DocIdSetIterator> getIterator, Func<IBits> bits, Func<bool> isCacheable)

Parameters

Type	Name	Description
Func<DocIdSetIterator>	getIterator	A delegate method that represents (is called by) the GetIterator() method. It returns the DocIdSetIterator for this DocIdSet.
Func<IBits>	bits	A delegate method that represents (is called by) the Bits property. It returns the IBits instance for this DocIdSet.
Func<System.Boolean>	isCacheable	A delegate method that represents (is called by) the IsCacheable property. It returns a value.

Returns

Type	Description
DocIdSet	A new Lucene.Net.Search.DocIdSet.AnonymousDocIdSet instance.

NewAnonymous(Func<DocIdSetIterator>, Func<Boolean>)

Creates a new instance with the ability to specify the body of the GetIterator() method through the getIterator parameter and the body of the IsCacheable property through the isCacheable parameter. Simple example:

    var docIdSet = DocIdSet.NewAnonymous(getIterator: () =>
    {
        OpenBitSet bitset = new OpenBitSet(5);
        bitset.Set(0, 5);
        return new DocIdBitSet(bitset);
    }, isCacheable: () =>
    {
        return true;
    });

LUCENENET specific

Declaration

public static DocIdSet NewAnonymous(Func<DocIdSetIterator> getIterator, Func<bool> isCacheable)

Parameters

Type	Name	Description
Func<DocIdSetIterator>	getIterator	A delegate method that represents (is called by) the GetIterator() method. It returns the DocIdSetIterator for this DocIdSet.
Func<System.Boolean>	isCacheable	A delegate method that represents (is called by) the IsCacheable property. It returns a value.

Returns

Type	Description
DocIdSet	A new Lucene.Net.Search.DocIdSet.AnonymousDocIdSet instance.